Rear Differential Acura TL IV

Scheme 1

Scheme 2

SH-AWD Indicator

The SH-AWD indicator will come on under certain conditions even if the AWD system is working normally Here are some examples

1. When you use high-powered wireless equipment such as a CB or Ham radio in the vehicle
2. When you keep spinning the rear wheels while the vehicle is stuck in sand, mud, snow, etc
3. When the battery voltage suddenly drops below 10 volt

After the SH-AWD indicator comes on, it stays on until you turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode

Diagnostic Trouble Code (DTC)

1. The SH-AWD control unit can memorize up to eight different DTCs The system displays the DTCs by blinking the SH-AWD indicator Multiple DTCs are displayed in the order they occurred, beginning with the most recent
2. If the same DTC is detected more than once, the most recent DTC is written over the earlier one Therefore, when the same problem is detected more than once, it is memorized as a single DTC
3. The DTCs are memorized in the SH-AWD units EEPROM (non-volatile memory) Therefore, the memorized DTCs are not cleared when the battery is disconnected or when the SH-AWD control unit is disconnected
4. If there is a problem in the central processing unit (CPU) of the SH-AWD control unit, the SH-AWD indicator comes on, but no DTC is memorized Refer to the «SYMPTOM TROUBLESHOOTING»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential)

Self-diagnosis

When a problem is detected during self-diagnosis, the system does the following

1. Turns the SH-AWD indicator on
2. Memorizes the DTC if possible
3. Stops AWD control and puts the vehicle back into two-wheel drive (front wheel only)
4. Reduces engine torque to suit the driving conditions when an abnormality was detected (The client may notice a decrease in engine performance)

Scheme 3

1. With the ignition switch in LOCK (0), or the vehicle in the OFF mode, connect the HDS to the data link connector (DLC) (A) located under the driver's side of the dashboard
2. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
3. Make sure the HDS communicates with the vehicle and the SH-AWD control unit If it does not, go to the DLC circuit troubleshooting (see «DLC CIRCUIT TROUBLESHOOTING»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__dlc-circuit-troubleshooting) )
4. Check the diagnostic trouble code (DTC) and the freeze data, for all systems in the vehicle, troubleshoot the powertrain DTCs first and note them. Then refer to the indicated DTC's troubleshooting, and do the appropriate troubleshooting procedure.

Note. The HDS can read the DTC, the freeze data, the current data, and other system data For specific operations, refer to the Help menu that came with the HDS It is best do an ALL DTC CHECK to look for other systems DTCs that are related to the problem

Scheme 4

1. With the ignition switch in LOCK (0), or the vehicle in the OFF mode, connect the HDS to the data link connector (DLC) (A) located under the driver's side of the dashboard
2. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
3. Make sure the HDS communicates with the vehicle and the SH-AWD control unit If it does not go to the DLC circuit troubleshooting (see «DLC CIRCUIT TROUBLESHOOTING»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__dlc-circuit-troubleshooting) )
4. Clear the DTC(s) by following the screen prompts on the HDS
5. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode

Note. If the DTC that was cleared is related to another system, that system's DTC must be repaired, or the SH-AWD DTC will return

How to Check for Diagnostic Trouble Codes (DTCs)

When the SH-AWD control unit senses an abnormality in the input or output systems, the SH-AWD indicator in the gauge control module will usually come on, and the malfunction indicator lamp (MIL), the D indicator, the VSA indicator, and/or the ABS indicator may also come on

Note. Check the vehicle battery condition and charging system before troubleshooting

Scheme 5

1. With the ignition switch in LOCK (0), or the vehicle in the OFF mode, connect the HDS to the data link connector (DLC) (A) located under the driver's side of the dashboard
2. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode Make sure the HDS communicates with the vehicle and the SH-AWD control unit If it does not, go to the DLC circuit troubleshooting (see «DLC CIRCUIT TROUBLESHOOTING»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__dlc-circuit-troubleshooting) ) Follow the prompts on the HDS to display the DTC (s) on the screen Check the DTC and the freeze data for all systems After determining the DTC(s), refer to the «DTC TROUBLESHOOTING»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) NOTE: See the for specific instructions
3. If there are fuel and emissions DTCs, A/T DTCs, and VSA system DTCs at the same time, troubleshoot the fuel and emissions DTCs first, otherwise the SH-AWD DTC may return
4. After recording the DTCs, clear all DTCs
5. Test-drive the vehicle for several minutes in AWD mode, and check for DTCs If the DTC returns, refer to the «DTC TROUBLESHOOTING»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) If the DTC does not return, there was an intermittent problem within the circuit Make sure all connectors and terminals in the circuit are tight

How to Troubleshoot Circuits at the SH-AWD Control Unit

Special Tools Required

Backprobe set 07SAZ-001000A (two required)

Scheme 6

Scheme 7

1. Remove the trunk front trim panel (see «TRIM REMOVAL/INSTALLATION - TRUNK AREA»(/acura/tl/iv-2008-2011/remont/exteriorinterior-trim/#interior-trim__trim-removalinstallation-trunk-area) )
2. Remove the SH-AWD control unit (A)
3. Inspect the circuit on the SH-AWD control unit according to the DTC Troubleshooting using the backprobe set and a digital multimeter or an analog circuit tester
4. Connect the backprobe adapters (A) to the stacking patch cords (B), and connect the cords to a digital multimeter or an analog circuit tester (C) Using the wire insulator as a guide for the contoured-tip of the backprobe adapter, gently slide the tip into the connector from the wire side until it comes in contact with the terminal end of the wires

SH-AWD Control Unit Update

Special Tools Required

1. Honda diagnostic system (HDS)
2. Honda interface module (HIM)
3. HDS pocket tester
4. MVCI unit with the latest control module (CM) update software installed

Note. Before you update the SH-AWD control unit, make sure the battery in the vehicle is fully charged Use this procedure when you need to update the SH-AWD control unit in a troubleshooting procedure Make sure the HDS/HIM has the latest software version Never turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode during the update If there is a problem with the update, leave the ignition switch in ON (II), or the vehicle in the ON mode, otherwise the control unit could be damaged, or it will set DTCs To prevent SH-AWD control unit damage, do not operate anything electrical (headlights, audio system, brakes, A/C, power windows, moonroof, door locks, etc) during the update To ensure the latest program is installed, do an SH-AWD control unit update whenever the SH-AWD control unit is substituted or replaced You cannot update an SH-AWD control unit with the same program it already has installed It will only accept a new program If you need to diagnose the Honda interface module (HIM) because the HIM's red (#3) light came on or was flashed during the update, leave the ignition switch in the ON (II) position, or the engine start/stop button in the ON mode, when you disconnect the HIM from the data link connector (DLC) This will prevent SH-AWD control unit damage

Scheme 8

1. With the ignition switch in LOCK (0), or the vehicle in the OFF mode, connect the HDS/HIM to the DLC (A) located under the driver's side of the dashboard
2. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
3. Make sure the HDS communicates with the vehicle and the SH-AWD control unit If it does not, go to the DLC circuit troubleshooting (see «DLC CIRCUIT TROUBLESHOOTING»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__dlc-circuit-troubleshooting) )
4. Select the update program, and follow the screen prompts to update the SH-AWD control unit
5. If the software in the SH-AWD control unit is the latest, disconnect the HDS/HIM from the DLC, and go back to the procedure that you were doing If the software in the SH-AWD control unit is not the latest, follow the instructions on the screen
6. Do the SH-AWD control unit initialization (see «YAW RATE-LATERAL/LONGITUDINAL ACCELERATION NEUTRAL POSITION MEMORIZATION»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__yaw-rate-laterallongitudinal-acceleration-neutral-position-m) )
7. Do the SH-AWD differential clutch torque memorization (see «SH-AWD DIFFERENTIAL CLUTCH TORQUE MEMORIZATION»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-differential-clutch-torque-memorization) )
8. Do the yaw rate-lateral/longitudinal acceleration neutral position memorization (see «YAW RATE-LATERAL/LONGITUDINAL ACCELERATION NEUTRAL POSITION MEMORIZATION»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__yaw-rate-laterallongitudinal-acceleration-neutral-position-m) )

SH-AWD Differential Clutch Torque Memorization

Whenever the right or left clutch side case is replaced, the differential clutch torque memorization must be done

Scheme 9

1. With the ignition switch in LOCK (0), or the vehicle in the OFF mode, connect the HDS to the DLC (A) located under the driver's side of the dashboard
2. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
3. Make sure the HDS communicates with the vehicle and the SH-AWD control unit If it does not, go to the DLC circuit troubleshooting (see «DLC CIRCUIT TROUBLESHOOTING»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__dlc-circuit-troubleshooting) )
4. From the mode menu, select SH-AWD, select MISCELLANEOUS TEST, select NEUTRAL MENU, then select DIFFERENTIAL TORQUE with the HDS, and follow the screen prompts

Note. See the HDS help menu for specific instructions

Yaw Rate-Lateral/Longitudinal Acceleration Neutral Position Memorization

Whenever the yaw rate-lateral/longitudinal acceleration sensor is replaced, its neutral position memorization must be done

Scheme 10

1. With the ignition switch in LOCK (0), or the vehicle in the OFF mode, connect the HDS to the DLC (A) located under the driver's side of the dashboard
2. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
3. Make sure the HDS communicates with the vehicle and the SH-AWD control unit If it does not, go to the DLC circuit troubleshooting (see «DLC CIRCUIT TROUBLESHOOTING»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__dlc-circuit-troubleshooting) )
4. From the mode menu, select SH-AWD, select MISCELLANEOUS TEST, select NEUTRAL MENU, then select ALL SENSORS with the HDS, and follow the screen prompts

Note. See the HDS help menu for specific instructions

SH-AWD Control Unit Initialization

Whenever the SH-AWD control unit is replaced, it must be initialized

Scheme 11

1. With the ignition switch in LOCK (0), or the vehicle in the OFF mode, connect the HDS to the DLC (A) located under the driver's side of the dashboard
2. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
3. Make sure the HDS communicates with the vehicle and the SH-AWD control unit If it does not, go to the DLC circuit troubleshooting (see «DLC CIRCUIT TROUBLESHOOTING»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__dlc-circuit-troubleshooting) )
4. From the mode menu, select SH-AWD, select MISCELLANEOUS TEST, then select INITIALIZATION with the HDS, and follow the screen prompts

Note. See the HDS help menu for specific instructions

DTC Troubleshooting Index

Symptom Troubleshooting Index

Note. Most problems in the SH-AWD unit can be diagnosed by identifying noises from the gears or bearings Care should be taken during diagnosis not to confuse differential noises with those from other drivetrain components

Outline

This vehicle is equipped with a Super Handling All-Wheel Drive® (SH-AWD®) rear differential system This system uses the electromagnetic clutches and the SH-AWD control unit to control front to rear torque distribution and independent left to right rear torque distribution This allows the system to function as a limited slip differential and as a torque distribution system to improve standing start performance, straight-line stability, climbing, and cornering ability

SH-AWD features include

1. Independent torque distribution to the front and rear wheels, and to the left and right wheels for neutral handling when cornering
2. Controls differential (inside/outside) wheel speed in a turn to increase cornering stability
3. Limited slip differential function for better acceleration

Operation

In a normal turn, the radius of the front wheels is shorter than the radius that the rear wheels travel If the front and rear wheels are driven at the same speed, full power is not transmitted The SH-AWD system monitors the speed of the front wheels and increases the speed of the outside rear wheel proportionally around the larger radius This improves stability and steering response On slippery surfaces, this provides the improved traction of a 4-wheel drive system

Scheme 12

Construction

1. The differential assembly has a conventional hypoid ring and pinion gear set
2. The direct electromagnetic clutch system consists of the coils, the planetary gear sets, and the multi-plate clutches that are installed in the side cases on either side of the differential carrier When driving straight ahead, both rear wheels rotate at the same speed When turning, current is applied to the appropriate outside wheel main coil to engage the clutch The amount of current passed through the electromagnetic clutch controls the amount of driving force to the outside wheel

Scheme 13

Control System

The SH-AWD control system consists of a SH-AWD control unit, the PCM, the VSA modulator-control unit, along with various sensors and switches that detect the steering angle, the lateral G force, the yaw, and the vehicle speed A fluid temperature sensor is located on the rear differential The control units exchange information via the CAN communication lines The SH-AWD control unit has a self-diagnostic function If a malfunction is detected, the SH-AWD control unit turns on the SH-AWD indicator in the gauge control module, and the system goes into fail-safe mode When in fail-sate mode, the vehicle disables the SH-AWD differential The vehicle defaults to front wheel drive and reduces engine torque to suit the driving conditions

Driving Force Control

The driving force control distributes the power based on the driver's inputs It distributes torque to the front and rear wheels based on the throttle opening and the available engine torque output When turning, torque is applied to the rear wheels independently based on the lateral G input and the direction of the turn This generates an inward yaw movement to help steer the vehicle around the turn

Scheme 14

The electromagnetic clutch system is incorporated into the side case assemblies on both sides of the differential case The system consists of the multi-plate clutches, the planetary gears, the pressure guides, the solenoid coil assembly (the search coil and the main coil), the armature assembly (the slider and the armature), and the yoke

COMPONENTS CHART

Scheme 15

The SH-AWD control unit receives inputs from the PCM and the VSA modulator-control unit on the driving conditions via the CAN The SH-AWD control unit sends signals to the main coils, which engage the electromagnetic clutches that connect the planetary gear set This increases the torque applied to the rear wheels The amount of current sent to the clutch is continuously varied as driving conditions change

Scheme 16

Search Coil Detection System

As the clutch discs wear, the air gap between the pressure guides and the multi-plate clutches decrease The decrease in air gap changes the magnetic field generated by the main coil and the yoke The search coil detects these changes in the magnetic field The SH-AWD control unit uses predetermined maps to compensate for the changes to maintain precise control and smooth clutch engagement

Scheme 17

Scheme 18

SH-AWD Control Unit Inputs and Outputs

The SH-AWD control unit terminal voltages and the measuring conditions for the SH-AWD inputs and outputs test are done with the SH-AWD connectors connected

Scheme 19

TERMINAL VOLTAGE CHART

The SH-AWD control unit terminal voltages and the measuring conditions for the SH-AWD inputs and outputs test are done with the SH-AWD connectors connected

Scheme 20

TERMINAL VOLTAGE CHART

Scheme 21

Scheme 22

DTC 12-1, 12-2, 12-3: Lateral Acceleration Sensor Malfunction

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Turn the ignition switch to LOCK (0), then turn the ignition switch back to ON (II), or select the OFF mode, then the ON mode
4. Check for DTCs in the VSA system with the HDS Are any lateral acceleration sensor DTCs indicated? YES -Go to the indicated DTC's troubleshooting NO -Go to step 5
5. Check for DTCs with the HDS Is DTC 12-1, 12-2, or 12-3 indicated? YES -Go to step 6 NO -Intermittent failure, the system is OK at this time
6. Test-drive the vehicle with an assistant Drive in a left and right zig-zag pattern at about 13 mph (20 km/h) and check the LATERAL ACCELERATION SENSOR in the SH-AWD mode menu DATA LIST with the HDS Does the sensor value change when turning? YES -Go to step 7 NO -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) )
7. Park the vehicle on a level surface
8. Check the LATERAL ACCELERATION SENSOR in the SH-AWD mode menu DATA LIST with the HDS Is there 0 1G or less? YES -Go to step 9 NO -Do the yaw rate-lateral/longitudinal acceleration neutral position memorization (see «YAW RATE-LATERAL/LONGITUDINAL ACCELERATION NEUTRAL POSITION MEMORIZATION»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__yaw-rate-laterallongitudinal-acceleration-neutral-position-m) ), and recheck
9. Check the LATERAL ACCELERATION SENSOR in the VSA DATA LIST with the HDS Is there 0 1G or less? YES -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete. If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ) NO -Replace the yaw rate-lateral/longitudinal acceleration sensor (see «YAW RATE-LATERAL ACCELERATION SENSOR REPLACEMENT»(/acura/tl/iv-2008-2011/remont/anti-locktraction-control/#vsa-vehicle-stability-assist-system-components) )

DTC 15-1: Longitudinal Acceleration Sensor Malfunction

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Test-drive the vehicle for 2 minutes in a vehicle speed is kept constant at 19 mph (30 km/h)
4. Check for DTCs in the VSA system with the HDS Are any longitudinal acceleration sensor DTCs indicated? YES -Go to the indicated DTC's troubleshooting NO -Go to step 5
5. Check for DTCs with the HDS Is DTC 15-1 indicated? YES -Go to step 6 NO -Intermittent failure, the system is OK at this time
6. Test-drive the vehicle with an assistant When accelerating, check the LONGITUDINAL ACCELERATION SENSOR in the SH-AWD mode menu DATA LIST with the HDS Does the sensor value change when acceleration? YES -Go to step 7 NO -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) )
7. Park the vehicle on a level surface
8. Check the LONGITUDINAL ACCELERATION SENSOR in the SH-AWD mode menu DATA LIST with the HDS Is there 0 1G or less? YES -Go to step 9 NO -Do the yaw rate-lateral/longitudinal acceleration neutral position memorization (see «YAW RATE-LATERAL/LONGITUDINAL ACCELERATION NEUTRAL POSITION MEMORIZATION»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__yaw-rate-laterallongitudinal-acceleration-neutral-position-m) ), and recheck
9. Check the LONGITUDINAL ACCELERATION SENSOR in the VSA DATA LIST with the HDS Is there 0 1 G or less? YES -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ) NO -Replace the yaw rate-lateral/longitudinal acceleration sensor (see «YAW RATE-LATERAL ACCELERATION SENSOR REPLACEMENT»(/acura/tl/iv-2008-2011/remont/anti-locktraction-control/#vsa-vehicle-stability-assist-system-components) )

DTC 16-3: Steering Angle Sensor Neutral Position Incorrect

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ) Check the wheel alignment (see WHEEL ALIGNMENT ) Check for installation of the steering angle sensor

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Test-drive the vehicle for 2 minutes in a straight line at 19 mph (30 km/h) or more
4. Check for DTCs in the VSA system with the HDS Are any steering angle sensor DTCs indicated? YES -Go to the indicated DTC's troubleshooting NO -Go to step 5
5. Check for DTCs with the HDS Is DTC 16-3 indicated? YES -Go to step 6 NO -Intermittent failure, the system is OK at this time
6. Start the engine
7. Check the STEERING ANGLE SENSOR in the SH-AWD mode menu DATA LIST with the HDS When the steering wheels is turned slowly, does the value change? YES -Go to step 8 NO -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) )
8. Test-drive the vehicle in a straight line at 19 mph (30 km/h) or more
9. Park the vehicle on a level surface, and center the steering wheel
10. Check the STEERING ANGLE SENSOR in the SH-AWD mode menu DATA LIST with the HDS Is it within ± 25 deg of center? YES -Go to step 11 NO -Do the steering angle sensor center point writing (see «VSA SENSOR NEUTRAL POSITION MEMORIZATION»(/acura/tl/iv-2008-2011/remont/anti-locktraction-control/#vsa-vehicle-stability-assist-system-components__vsa-sensor-neutral-position-memorization) ), and recheck
11. Check the STEERING ANGLE SENSOR in the VSA DATA LIST with the HDS Is it within ± 25 deg of center? YES -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ) NO -Replace the steering angle sensor (see «STEERING ANGLE SENSOR REPLACEMENT»(/acura/tl/iv-2008-2011/remont/anti-locktraction-control/#vsa-vehicle-stability-assist-system-components__steering-angle-sensor-replacement) )

DTC 33-2, 33-3: Yaw Rate Sensor Malfunction

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Turn the ignition switch to LOCK (0), then turn the ignition switch back to ON (II), or select the OFF mode, then the ON mode
4. Check for DTCs in the VSA system with the HDS Are any yaw rate sensor DTCs indicated? YES -Go to the indicated DTC's troubleshooting NO -Go to step 5
5. Check for DTCs with the HDS Is DTC 33-2 or 33-3 indicated? YES -Go to step 6 NO -Intermittent failure, the system is OK at this time
6. Test-drive the vehicle with an assistant Drive in a left and right zig-zag pattern at about 13 mph (20 km/h) and check the YAW RATE SENSOR in the SH-AWD mode menu DATA LIST with the HDS Does the sensor value change when turning? YES -Go to step 7 NO -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) )
7. Park the vehicle on a level surface
8. Check the YAW RATE SENSOR in the SH-AWD mode menu DATA LIST with the HDS Is there 3 5 deg/s or less? YES -Go to step 9 NO -Do the yaw rate-lateral/longitudinal acceleration neutral position memorization (see «YAW RATE-LATERAL/LONGITUDINAL ACCELERATION NEUTRAL POSITION MEMORIZATION»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__yaw-rate-laterallongitudinal-acceleration-neutral-position-m) ), and recheck
9. Check the YAW RATE SENSOR in the VSA DATA LIST with the HDS Is there 3 5 deg/s or less? YES -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ) NO -Replace the yaw rate-lateral/longitudinal acceleration sensor (see «YAW RATE-LATERAL ACCELERATION SENSOR REPLACEMENT»(/acura/tl/iv-2008-2011/remont/anti-locktraction-control/#vsa-vehicle-stability-assist-system-components) )

DTC 41-1: F-CAN Malfunction (Lost Communication with Powertrain Control Module (PCM))

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

Scheme 23

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Start the engine
4. Check for DTCs in the PGM-FI system with the HDS Are there any PGM-FI system DTCs indicated? YES -Go to the indicated DTC's troubleshooting NO -Go to step 5
5. Check for DTCs with the HDS Is DTC 41-1 indicated? YES -Go to step 6 NO -Intermittent failure, the system is OK at this time Check for intermittent open between SH-AWD control unit connector terminals A10 and A20 and PCM connector terminals A48 and A49
6. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
7. Jump the SCS line with the HDS NOTE: This step must be done to prevent PCM damage
8. Disconnect PCM connector A (49P)
9. Disconnect SH-AWD control unit connector A (20P)
10. Check for continuity between PCM connector terminals A48, A49 and SH-AWD control unit connector terminals A10, A20 individually Is there continuity? YES -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ) NO -Repair open in the wires between the SH-AWD control unit and the PCM

DTC 41-2: F-CAN Malfunction (Lost Communication with VSA Modulator-Control Unit)

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

Scheme 24

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Start the engine
4. Check for DTCs in the PGM-FI system with the HDS Are there any PGM-FI system DTCs indicated? YES -Go to the indicated DTC's troubleshooting NO -Go to step 5
5. Check for DTCs with the HDS Is DTC 41-2 indicated? YES -Go to step 6 NO -Intermittent failure, the system is OK at this time Check for intermittent open between SH-AWD control unit connector terminals A10 and A20 and VSA modulator-control unit 47P connector terminals No 12 and No 13
6. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
7. Disconnect the VSA modulator-control unit 47P connector
8. Disconnect SH-AWD control unit connector A (20P)
9. Check for continuity between VSA modulator-control unit 47P connector terminals No 12, No 13 and SH-AWD control unit connector terminals A10, A20 individually Is there continuity? YES -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ) NO -Repair open in the wires between the SH-AWD control unit and the VSA modulator-control unit

DTC 41-4: F-CAN Malfunction (Lost Communication with A/T Control System)

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

Scheme 25

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Start the engine
4. Check for DTCs in the PGM-FI system with the HDS Are there any PGM-FI system DTCs indicated? YES -Go to the indicated DTC's troubleshooting NO -Go to step 5
5. Check for DTCs with the HDS Is DTC 41-4 indicated? YES -Go to step 6 NO -Intermittent failure, the system is OK at this time Check for intermittent open between SH-AWD control unit connector terminals A10 and A20 and PCM connector terminals A48 and A49
6. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
7. Jump the SCS line with the HDS NOTE: This step must be done to prevent PCM damage
8. Disconnect PCM connector A (49P)
9. Disconnect SH-AWD control unit connector A (20P)
10. Check for continuity between PCM connector terminals A48, A49 and SH-AWD control unit connector terminals A10, A20 individually Is there continuity? YES -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ) NO -Repair open in the wires between the SH-AWD control unit and the PCM

DTC 41-5: F-CAN Malfunction (Lost Communication with Yaw Rate-Lateral/Longitudinal Acceleration Sensor)

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

Scheme 26

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Start the engine
4. Check for DTCs in the VSA system with the HDS Are any yaw rate-lateral/longitudinal acceleration sensor DTCs of F-CAN indicated? YES -Go to the indicated DTC's troubleshooting NO -Go to step 5
5. Check for DTCs with the HDS Is DTC 41-5 indicated? YES -Go to step 6 NO -Intermittent failure, the system is OK at this time Check for intermittent open between SH-AWD control unit connector terminals A10 and A20 and yaw rate-lateral/longitudinal acceleration sensor 4P connector terminals No 2 and No 3
6. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
7. Disconnect the yaw rate-lateral/longitudinal acceleration sensor 4P connector
8. Disconnect SH-AWD control unit connector A (20P)
9. Check for continuity between yaw-rate lateral/longitudinal acceleration sensor 4P connector terminals No 2, No 3 and SH-AWD control unit connector terminals A10, A20 individually Is there continuity? YES -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ) NO -Repair open in the wire between the SH-AWD control unit and the yaw rate-lateral/longitudinal acceleration sensor

DTC 41-6: F-CAN Malfunction (Lost Communication with Steering Angle Sensor)

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

Scheme 27

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Start the engine
4. Check for DTCs in the VSA system with the HDS Are any steering angle sensor DTCs of F-CAN indicated? YES -Go to the indicated DTC's troubleshooting NO -Go to step 5
5. Check for DTCs with the HDS Is DTC 41-6 indicated? YES -Go to step 6 NO -Intermittent failure, the system is OK at this time Check for intermittent open between SH-AWD control unit connector terminals A10 and A20 and steering angle sensor 5P connector terminals No 2 and No 4
6. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
7. Disconnect the steering angle sensor 5P connector
8. Disconnect SH-AWD control unit connector A (20P)
9. Check for continuity between steering angle sensor 5P connector terminals No 2, No 4 and SH-AWD control unit connector terminals A10, A20 individually Is there continuity? YES -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ) NO -Repair open in the wires between the SH-AWD control unit and the steering angle sensor

DTC 42-1: Differential Fluid Temperature Sensor (Short to Power)

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ) If the vehicle was driven prior to this troubleshooting procedure, allow the rear differential to cool for more than an hour before continuing

Scheme 28

Scheme 29

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Turn the ignition switch to LOCK (0), then turn the ignition switch back to ON (II), or select the OFF mode, then the ON mode
4. Check for DTCs with the HDS Is DTC 42-1 indicated? YES -Go to step 5 NO -Intermittent failure, the system is OK at this time
5. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
6. Disconnect the rear differential fluid temperature sensor 2P connector
7. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
8. Check the REAR DIFFERENTIAL FLUID TEMPERATURE SENSOR in the DATA LIST with the HDS Is there -18°F (-28°C) or more? YES -Go to step 9 NO -Replace the rear differential fluid temperature sensor (see «REAR DIFFERENTIAL FLUID TEMPERATURE SENSOR REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) )
9. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
10. Disconnect SH-AWD control unit connector A (20P)
11. Check for continuity between rear differential fluid temperature sensor 2P connector terminals No 1 and No 2 Is there continuity? YES -Repair short in the wire between rear differential fluid temperature sensor 2P connector terminals No 1 and No 2 NO -Go to step 12
12. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
13. Measure the voltage between body ground and rear differential fluid temperature sensor 2P connector terminals No. 1 and No. 2 respectivery. Is there about 5 V or more? YES -Repair a short to power in the wire harness. NO -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) )

DTC 42-2: Differential Fluid Temperature Sensor (Open/GND Short)

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

Scheme 30

Scheme 31

Scheme 32

Scheme 33

Scheme 34

Scheme 35

Scheme 36

1. Raise the vehicle on a lift, make sure it is securely supported, and allow all four wheels to rotate freely
2. Start the engine and turn the VSA off (the VSA OFF lamp in the gauge control module turns on) Run the engine in D until the vehicle speed reaches 35 mph (56 km/h) and maintain the speed for 10 minutes, then slow down and stop the wheels
3. Turn the ignition switch to LOCK (0), then turn the ignition switch back to ON (II), or select the OFF mode, then the ON mode
4. Clear the DTC with the HDS
5. Check for DTCs with the HDS Is DTC 42-2 indicated? YES -Go to step 6 NO -Intermittent failure, the system is OK at this time
6. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
7. Disconnect the rear differential fluid temperature sensor 2P connector
8. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
9. Measure the voltage between rear differential fluid temperature sensor 2P connector terminals No 1 and No 2 Is there about 4 V? YES -Replace the rear differential fluid temperature sensor (see «REAR DIFFERENTIAL FLUID TEMPERATURE SENSOR REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) ) NO -Go to step 10
10. Measure the voltage between rear differential fluid temperature sensor 2P connector terminal No 1 and body ground Is there about 4 V? YES -Go to step 15 NO -Go to step 12
11. Measure the voltage between SH-AWD control unit connector terminal A18 and body ground Is there about 4 V? YES -Repair open in the wire between SH-AWD control unit connector terminal A18 and rear differential fluid temperature sensor 2P connector terminal No 1 NO -Go to step 12
12. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
13. Disconnect SH-AWD control unit connector A (20P)
14. Check for continuity between rear differential fluid temperature sensor 2P connector terminal No 1 and body ground Is there continuity? YES -Repair short to body ground in the wire between SH-AWD control unit connector terminal A18 and the rear differential fluid temperature sensor 2P connector NO -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) )
15. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
16. Disconnect SH-AWD control unit connector A (20P)
17. Check for continuity between rear differential fluid temperature sensor 2P connector terminal No 2 and body ground Is there continuity? YES -Repair short to body ground in the wire between SH-AWD control unit connector terminal A8 and the rear differential fluid temperature sensor 2P connector NO -Go to step 18
18. Connect SH-AWD control unit connector terminal A8 to body ground with a jumper wire
19. Check for continuity between rear differential fluid temperature sensor 2P connector terminal No 2 and body ground Is there continuity? YES -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ) NO -Repair open in the wire between SH-AWD control unit connector terminal A8 and the rear differential fluid temperature sensor 2P connector

DTC 43-1: Differential Fluid Temperature Sensor Malfunction

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

Scheme 37

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Check for DTCs with the HDS Is DTC 42-1 or 42-2 indicated? YES -Go to the indicated DTC's troubleshooting NO -Go to step 3
3. Clear the DTC with the HDS
4. Start the engine, and let it idle for 1 minute
5. Test-drive the vehicle for 5 minutes
6. Check for DTCs with the HDS Is DTC 43-1 indicated? YES -Go to step 7 NO -Intermittent failure, the system is OK at this time
7. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
8. Disconnect SH-AWD control unit connector A (20P) and the rear differential fluid temperature sensor 2P connector
9. Check for continuity between rear differential fluid temperature sensor 2P connector terminals No 1 and No 2 Is there continuity? YES -Repair short in the wires between rear differential fluid temperature sensor 2P connector terminals No 1 and No 2 NO -Go to step 10
10. Reconnect all connectors
11. Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) )
12. Start the engine, and let it idle for 1 minute
13. Check for DTCs with the HDS Is DTC 43-1 indicated? YES -Replace the rear differential fluid temperature sensor (see «REAR DIFFERENTIAL FLUID TEMPERATURE SENSOR REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) ) NO -Replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) )

DTC 44-11: SH-AWD Control Unit

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Turn the ignition switch to LOCK (0), then turn the ignition switch back to ON (II), or select the OFF mode, then the ON mode
4. Check for DTCs with the HDS Is DTC 44-11 indicated? YES -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ) NO -Intermittent failure, the system is OK at this time

DTC 44-12: SH-AWD Relay Stuck ON

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

Scheme 38

Scheme 39

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Start the engine
4. Check for DTCs with the HDS Is DTC 44-12 indicated? YES -Go to step 5 NO -Intermittent failure, the system is OK at this time
5. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
6. Remove the SH-AWD relay (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), then test the SH-AWD relay (see «POWER RELAY TEST»(/acura/tl/iv-2008-2011/remont/body-electrical/#relays__power-relay-test) ) Is the SH-AWD relay OK? YES -Go to step 7 NO -Replace the SH-AWD relay (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) )
7. Disconnect SH-AWD control unit connector A (20P)
8. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
9. Measure the voltage between SH-AWD control unit connector terminal A17 and body ground Is there battery voltage? YES -Repair short to power in the wire between the SH-AWD control unit connector terminal A17 and the SH-AWD relay (FSR line) NO -Go to step 10
10. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
11. Disconnect SH-AWD control unit connector B (8P)
12. Measure the voltage between SH-AWD control unit connector terminals B1 and B2 Is there battery voltage? YES -Repair short to power in the wire between the SH-AWD control unit and the SH-AWD relay (PWR line) NO -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) )

DTC 44-32: SH-AWD Control Unit Power Supply Stuck ON; DTC 44-41: SH-AWD Control Unit Power Supply Stuck OFF

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Start the engine
4. Check for DTCs with the HDS Is DTC 44-32 or 44-41 indicated? YES -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ) NO -Intermittent failure, the system is OK at this time

DTC 44-50: SH-AWD Control Unit Power Supply Voltage Low

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ) Make sure the battery is fully charged and the charging system is working properly

Scheme 40

Scheme 41

Scheme 42

Scheme 43

Scheme 44

Scheme 45

1. Check the No 2-6 (30 A) fuse in the under-hood fuse/relay box Is the fuse OK? YES -Go to step 2 NO -Replace the blown fuse and recheck If the No 2-6 (30 A) fuse blows again, repair short to ground in the wire between the No 2-6 (30 A) fuse in the under-hood fuse/relay box and the SH-AWD relay 4P connector, then replace the fuse and recheck
2. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
3. Clear the DTC with the HDS
4. Start the engine
5. Check for DTCs with the HDS Is DTC 44-50 indicated? YES -Go to step 6 NO -Intermittent failure, the system is OK at this time
6. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
7. Remove the SH-AWD relay (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), then test the SH-AWD relay (see «POWER RELAY TEST»(/acura/tl/iv-2008-2011/remont/body-electrical/#relays__power-relay-test) ) Is the SH-AWD relay OK? YES -Go to step 8 NO -Replace the SH-AWD relay (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) )
8. Measure the voltage between SH-AWD relay 4P connector terminal No 1 and body ground Is there battery voltage? YES -Go to step 9 NO -Repair open in the wire between the No 2-6 (30 A) fuse in the under-hood fuse/relay box and the SH-AWD relay 4P connector
9. Disconnect SH-AWD control unit connector A (20P) and connector B (8P)
10. Connect SH-AWD relay 4P connector terminals No 1 and No 2 with a jumper wire
11. Measure the voltage between SH-AWD control unit connector terminal B1 and body ground Is there voltage? YES -Go to step 12 NO -Repair open in the wire between SH-AWD control unit connector terminal B1 and the SH-AWD relay 4P connector
12. Check for continuity between SH-AWD relay 4P connector terminal No 3 and body ground Is there continuity? YES -Go to step 13 NO -Repair open in the wire between the SH-AWD relay 4P connector and body ground, or repair poor body ground at G652
13. Connect SH-AWD relay 4P connector terminals No 3 and No 4 with a jumper wire
14. Check for continuity between SH-AWD control unit connector terminal A17 and body ground Is there continuity? YES -Check for loose connector terminals at the SH-AWD control unit If the connections are OK, update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ) NO -Repair open in the wire between SH-AWD control unit connector terminal A17 and the SH-AWD relay 4P connector

DTC 49-1: SH-AWD Control Unit (PG Line Open)

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

Scheme 46

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Start the engine
4. Check for DTCs with the HDS Is DTC 49-1 indicated? YES -Go to step 5 NO -Intermittent failure, the system is OK at this time
5. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
6. Disconnect SH-AWD control unit connector B (8P)
7. Check for continuity between SH-AWD control unit connector terminal B2 and body ground Is there continuity? YES -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ) NO -Repair open in the wire between SH-AWD control unit connector terminal B2 and body ground, or repair poor body ground at G652

DTC 52-3: Left Clutch Electromagnetic Coil Current Malfunction

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ) If DTC 49-1 is stored at the same time as DTC 52-3, troubleshoot DTC 49-1 first, then recheck for DTC 52-3

Scheme 47

Scheme 48

Scheme 49

Scheme 50

Scheme 51

Scheme 52

Scheme 53

Scheme 54

Scheme 55

Scheme 56

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Do the clutch function test with the HDS (see «SH-AWD FUNCTION TEST»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-function-test) )
4. Check for DTCs with the HDS Is DTC 52-3 indicated? YES -Go to step 5 NO -Intermittent failure, the system is OK at this time
5. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
6. Disconnect SH-AWD control unit connector B (8P) and the left solenoid 4P connector
7. Connect left solenoid 4P connector terminal No 1 to body ground with a jumper wire
8. Check for continuity between SH-AWD control unit connector terminal B5 and body ground Is there continuity? YES -Go to step 9 NO -Repair open in the wire between the SH-AWD control unit connector terminal B5 and the left solenoid 4P connector
9. Remove the jumper wire from left solenoid 4P connector terminal No 1
10. Connect left solenoid 4P connector terminal No 2 to body ground with a jumper wire
11. Check for continuity between SH-AWD control unit connector terminal B4 and body ground Is there continuity? YES -Go to step 12 NO -Repair open in the wire between SH-AWD control unit connector terminal B4 and the left solenoid 4P connector
12. Remove the jumper wire from left solenoid 4P connector terminal No 2
13. Check for continuity between SH-AWD control unit connector terminal B2 and body ground Is there continuity? YES -Go to step 14 NO -Repair open in the wire between SH-AWD control unit connector terminal B2 and body ground (G652), or repair poor body ground (G652)
14. Check for continuity between SH-AWD control unit connector terminals B2 and B4 Is there continuity? YES -Repair short to body ground in the wire between SH-AWD control unit connector terminal B4 and the left solenoid 4P connector NO -Go to step 15
15. Check for continuity between SH-AWD control unit connector terminals B2 and B5 Is there continuity? YES -Repair short to body ground in the wire between SH-AWD control unit connector terminal B5 and the left solenoid 4P connector NO -Go to step 16
16. Check for continuity between SH-AWD control unit connector terminals B4 and B5 Is there continuity? YES -Repair short in the wires between the SH-AWD control unit and the left solenoid 4P connector NO -Go to step 17
17. Measure the voltage between SH-AWD control unit connector terminals B2 and B5 Is there voltage? YES -Repair short to power in the wire between SH-AWD control unit connector terminal B5 and the left solenoid 4P connector NO -Go to step 18
18. Measure the voltage between SH-AWD control unit connector terminals B2 and B4 Is there voltage? YES -Repair short to power in the wire between SH-AWD control unit connector terminal B4 and the left solenoid 4P connector NO -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) )

DTC 53-1, 53-3: Left Clutch Electromagnetic Coil (Open)

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

Scheme 57

Scheme 58

Scheme 59

Scheme 60

Scheme 61

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Do the clutch function test with the HDS (see «SH-AWD FUNCTION TEST»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-function-test) )
4. Check for DTCs with the HDS Is DTC 53-1 or 53-3 indicated? YES -Go to step 5 NO -Intermittent failure, the system is OK at this time
5. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
6. Disconnect SH-AWD control unit connector B (8P) and the left solenoid 4P connector
7. Connect left solenoid 4P connector terminal No 1 to body ground with a jumper wire
8. Check for continuity between SH-AWD control unit connector terminal B5 and body ground Is there continuity? YES -Go to step 9 NO -Repair open in the wire between SH-AWD control unit connector terminal B5 and the left solenoid 4P connector
9. Remove the jumper wire from left solenoid 4P connector terminal No 1
10. Connect left solenoid 4P connector terminal No 2 to body ground with a jumper wire
11. Check for continuity between SH-AWD control unit connector terminal B4 and body ground Is there continuity? YES -Go to step 12 NO -Repair open in the wire between SH-AWD control unit connector terminal B4 and the left solenoid 4P connector
12. Remove the jumper wire from left solenoid 4P connector terminal No 2
13. Reconnect all connectors
14. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
15. Check the REAR DIFFERENTIAL FLUID TEMPERATURE SENSOR in the SH-AWD mode menu DATA LIST The temperature should be above 68°F (20°C) with the HDS before proceeding to the next step If the temperature is below 68°F (20°C), drive the vehicle to warm up the rear differential until the fluid temperature becomes above 68°F (20°C)
16. Turn the ignition switch to LOCK(0), or press the engine start/stop button to select the OFF mode
17. Disconnect the left solenoid 4P connector
18. Measure the resistance between left solenoid 4P connector terminals No 1 and No 2 Is there 1 8 ohms or more? YES -Replace the rear differential left side case (see «SIDE CASE REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) ) NO -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) )

DTC 53-2: Left Clutch Electromagnetic Coil (Short)

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

Scheme 62

Scheme 63

Scheme 64

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Do the clutch function test with the HDS (see «SH-AWD FUNCTION TEST»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-function-test) )
4. Check for DTCs with the HDS Is DTC 53-2 indicated? YES -Go to step 5 NO -Intermittent failure, the system is OK at this time
5. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
6. Disconnect SH-AWD control unit connector B (8P) and the left solenoid 4P connector
7. Check for continuity between SH-AWD control unit connector terminals B4 and B5 Is there continuity? YES -Repair short in the wires between SH-AWD control unit connector terminals B4 and B5 NO -Go to step 8
8. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
9. Measure the voltage between SH-AWD control unit connector terminal B4 and body ground Is there voltage? YES -Repair short to power in the wires between SH-AWD control unit connector terminal B4 and the left solenoid 4P connector NO -Go to step 10
10. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
11. Reconnect all connectors
12. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
13. Check the REAR DIFFERENTIAL FLUID TEMPERATURE SENSOR in the SH-AWD mode menu DATA LIST The temperature should be above 68°F (20°C) with the HDS before proceeding to the next step If the temperature is below 68°F (20°C), drive the vehicle to warm up the rear differential until the fluid temperature becomes above 68°F (20°C)
14. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
15. Disconnect the left solenoid 4P connector
16. Measure the resistance between left solenoid 4P connector terminals No 1 and No 2 Is there 0 45 ohms or less? YES -Replace the rear differential left side case (see «SIDE CASE REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) ) NO -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) )

DTC 56-3: Right Clutch Electromagnetic Coil Current Malfunction

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ) If DTC 49-1 is stored at the same time as DTC 56-3, troubleshoot DTC 49-1 first, then recheck for DTC 56-3

Scheme 65

Scheme 66

Scheme 67

Scheme 68

Scheme 69

Scheme 70

Scheme 71

Scheme 72

Scheme 73

Scheme 74

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Do the clutch function test with the HDS (see «SH-AWD FUNCTION TEST»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-function-test) )
4. Check for DTCs with the HDS Is DTC 56-3 indicated? YES -Go to step 5 NO -Intermittent failure, the system is OK at this time
5. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
6. Disconnect SH-AWD control unit connector B (8P) and the right solenoid 4P connector
7. Connect right solenoid 4P connector terminal No 1 to body ground with a jumper wire
8. Check for continuity between SH-AWD control unit connector terminal B7 and body ground Is there continuity? YES -Go to step 9 NO -Repair open in the wire between SH-AWD control unit connector terminal B7 and the right solenoid 4P connector
9. Remove the jumper wire from right solenoid 4P connector terminal No 1
10. Connect right solenoid 4P connector terminal No 2 to body ground with a jumper wire
11. Check for continuity between SH-AWD control unit connector terminal B6 and body ground Is there continuity? YES -Go to step 12 NO -Repair open in the wire between SH-AWD control unit connector terminal B6 and the right solenoid 4P connector
12. Remove the jumper wire from right solenoid 4P connector terminal No 2
13. Check for continuity between SH-AWD control unit connector terminal B2 and body ground Is there continuity? YES -Go to step 14 NO -Repair open in the wire between SH-AWD control unit connector terminal B2 and body ground (G652), or repair poor body ground (G652)
14. Check for continuity between SH-AWD control unit connector terminals B2 and B6 Is there continuity? YES -Repair short to body ground in the wire between SH-AWD control unit connector terminal B6 and the right solenoid 4P connector NO -Go to step 15
15. Check for continuity between SH-AWD control unit connector terminals B2 and B7 Is there continuity? YES -Repair short to body ground in the wire between SH-AWD control unit connector terminal B7 and the right solenoid 4P connector NO -Go to step 16
16. Check for continuity between SH-AWD control unit connector terminals B6 and B7 Is there continuity? YES -Repair short in the wires between the SH-AWD control unit and the right solenoid 4P connector NO -Go to step 17
17. Measure the voltage between SH-AWD control unit connector terminals B2 and B7 Is there voltage? YES -Repair short to power in the wire between the SH-AWD control unit connector terminal B7 and the right solenoid 4P connector NO -Go to step 18
18. Measure the voltage between SH-AWD control unit connector terminals B2 and B6 Is there voltage? YES -Repair short to power in the wire between SH-AWD control unit connector terminal B6 and the right solenoid 4P connector NO -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) )

DTC 57-1, 57-3: Right Clutch Electromagnetic Coil (Open)

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

Scheme 75

Scheme 76

Scheme 77

Scheme 78

Scheme 79

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Do the clutch function test with the HDS (see «SH-AWD FUNCTION TEST»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-function-test) )
4. Check for DTCs with the HDS Is DTC 57-1 or 57-3 indicated? YES -Go to step 5 NO -Intermittent failure, the system is OK at this time
5. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
6. Disconnect SH-AWD control unit connector B (8P) and the right solenoid 4P connector
7. Connect right solenoid 4P connector terminal No 1 to body ground with a jumper wire
8. Check for continuity between SH-AWD control unit connector terminal B7 and body ground Is there continuity? YES -Go to step 9 NO -Repair open in the wire between SH-AWD control unit connector terminal B7 and the right solenoid 4P connector
9. Remove the jumper wire from right solenoid 4P connector terminal No 1
10. Connect right solenoid 4P connector terminal No 2 to body ground with a jumper wire
11. Check for continuity between SH-AWD control unit connector terminal B6 and body ground Is there continuity? YES -Go to step 12 NO -Repair open in the wire between SH-AWD control unit connector terminal B6 and the right solenoid 4P connector
12. Remove the jumper wire from right solenoid 4P connector terminal No 2
13. Reconnect all connectors
14. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
15. Check the REAR DIFFERENTIAL FLUID TEMPERATURE SENSOR in the SH-AWD mode menu DATA LIST The temperature should be above 68°F (20°C) with the HDS before proceeding to the next step If the temperature is below 68°F (20°C), drive the vehicle to warm up the rear differential until the fluid temperature becomes above 68°F (20°C)
16. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
17. Disconnect the right solenoid 4P connector
18. Measure the resistance between right solenoid 4P connector terminals No 1 and No 2 Is there 1 8 ohms or more? YES -Replace the rear differential right side case (see «SIDE CASE REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) ) NO -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) )

DTC 57-2: Right Clutch Electromagnetic Coil (Short)

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

Scheme 80

Scheme 81

Scheme 82

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Do the clutch function test with the HDS (see «SH-AWD FUNCTION TEST»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-function-test) )
4. Check for DTCs with the HDS Is DTC 57-2 indicated? YES -Go to step 5 NO -Intermittent failure, the system is OK at this time
5. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
6. Disconnect SH-AWD control unit connector B (8P) and the right solenoid 4P connector
7. Check for continuity between SH-AWD control unit connector terminals B6 and B7 Is there continuity? YES -Repair short in the wires between SH-AWD control unit connector terminals B6 and B7 NO -Go to step 8
8. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
9. Measure the voltage between SH-AWD control unit connector terminal B6 and body ground Is there voltage? YES -Repair short to power in the wires between SH-AWD control unit connector terminal B6 and the right clutch electromagnetic coil NO -Go to step 10
10. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
11. Reconnect all connectors
12. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
13. Check the REAR DIFFERENTIAL FLUID TEMPERATURE SENSOR in the SH-AWD mode menu DATA LIST The temperature should be above 68°F (20°C) with the HDS before proceeding to the next step If the temperature is below 68°F (20°C), drive the vehicle to warm up the rear differential until the fluid temperature becomes above 68°F (20°C)
14. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
15. Disconnect the right solenoid 4P connector
16. Measure the resistance between right solenoid 4P connector terminals No 1 and No 2 Is there 0 45 ohms or less? YES -Replace the rear differential right side case (see «SIDE CASE REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) ) NO -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) )

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ) When the temperature of the rear differential fluid is abnormally high, the SH-AWD indicator comes on. This is not necessarily a problem, but DTC 76-1 will be stored. Check the rear differential fluid level (see Rear Differential Fluid Inspection and Replacement ). If it is low, refill it, clear the DTC, and recheck.

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Check for DTCs in the VSA system with the HDS Are any VSA system DTCs indicated? YES -Go to the indicated DTCs troubleshooting NO -Go to step 3
3. Clear the DTC with the HDS
4. Start the engine
5. Test-drive the vehicle at 10 mph (15km/h), and check for WHEEL SPEED in the DATA LIST with the HDS
6. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
7. Check for rear brake drag Are the rear brakes OK? YES -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ) NO -Inspect and repair the rear brakes (see «BRAKE SYSTEM INSPECTION AND TEST»(/acura/tl/iv-2008-2011/remont/mechanical-hydraulic/#conventional-brake-components__brake-system-inspection-and-test) )

DTC 77-1: The Functional Abnormalities of Fuel and Emissions

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS.
3. Start the engine
4. Check for DTCs with the HDS Is DTC 77-1 indicated? YES -Go to step 5 NO -Intermittent failure, the system is OK at this time
5. Check for DTCs in the PGM-FI system with the HDS Are there any PGM-FI system DTCs indicated? YES -Go to the indicated DTC's troubleshooting NO -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) )

DTC 77-2: The Functional Abnormalities of VSA Modulator-Control Unit; DTC 77-5: Yaw Rate-Lateral/Longitudinal Acceleration Sensor Malfunction; DTC 77-6: Steering Angle Sensor Malfunction

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Start the engine
4. Check for DTCs with the HDS Is DTC 77-2, 77-5, or 77-6 indicated? YES -Go to step 5 NO -Intermittent failure, the system is OK at this time
5. Check for DTCs in the VSA system with the HDS Are there VSA system DTCs indicated? YES -Go to the indicated DTC's troubleshooting NO -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) )

DTC 77-4: The Functional Abnormalities of Automatic Transmission

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Start the engine
4. Check for DTCs with the HDS Is DTC 77-4 indicated? YES -Go to step 5 NO -Intermittent failure, the system is OK at this time
5. Check for DTCs in the A/T system with the HDS Are there any A/T system DTCs indicated? YES -Go to the indicated DTC's troubleshooting NO -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) )

DTC 78-xx ("x" can be 0 thru 9 or A thru F): SH-AWD Control Unit Self-Diagnostic Malfunction

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Start the engine
4. Check for DTCs with the HDS Is DTC 78-xx indicated? YES -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ) NO -Intermittent failure, the system is OK at this time

DTC 81-1: Left Search Coil Sensor Malfunction

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

Scheme 83

Scheme 84

Scheme 85

Scheme 86

Scheme 87

Scheme 88

Scheme 89

Scheme 90

1. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
2. Disconnect SH-AWD control unit connector A (20P)
3. Check for continuity between SH-AWD control unit connector terminals A1 and A11 Is there continuity? YES -Go to step 4 NO -Go to step 12
4. Check the REAR DIFFERENTIAL FLUID TEMPERATURE SENSOR in the SH-AWD mode menu DATA LIST The temperature should be above 68°F (20°C) with the HDS before proceeding to the next step If the temperature is below 68°F (20°C), drive the vehicle to warm up the rear differential until the fluid temperature becomes above 68°F (20°C)
5. Measure the resistance between SH-AWD control unit connector terminals A1 and A11 Is there about 2 0 ohms or more? YES -Go to step 8 NO -Go to step 6
6. Disconnect the left solenoid 4P connector.
7. Check for continuity between left solenoid 4P connector terminals No 3 and No 4 Is there continuity? YES -Repair short in the wires between SH-AWD control unit connector A and the left solenoid 4P connector NO -Replace the rear differential left side case (see «SIDE CASE REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) )
8. Check for continuity between SH-AWD control unit connector terminal A1 and body ground Is Mere continuity? YES -Repair short to body ground in the wire between SH-AWD control unit connector terminal A1 and body ground NO -Go to step 9
9. Check the connections at the SH-AWD control unit Are the connections loose or poor? YES -Repair the connections as needed, and recheck NO -Go to step 10
10. Update the SH-AWD control unit with the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), and recheck Does the symptom/indication go away? YES -Troubleshooting is complete NO -Go to step 11
11. Substitute the SH-AWD control unit with a known-good control unit, and recheck Does the symptom/indication go away? YES -Replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ) NO -Replace the rear differential left side case (see «SIDE CASE REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) ) NOTE: If a new SH-AWD control unit was used in place of the known-good control unit and the new control unit will not initialize, replace the rear differential left side case
12. Disconnect the left solenoid 4P connector
13. Connect left solenoid 4P connector terminal No 3 to body ground with a jumper wire
14. Check for continuity between SH-AWD control unit connector terminal A11 and body ground Is there continuity? YES -Go to step 15 NO -Repair open in the wire between SH-AWD control unit connector terminal A11 and the left solenoid 4P connector
15. Remove the jumper wire from left solenoid 4P connector terminal No 3
16. Connect left solenoid 4P connector terminal No 4 to body ground with a jumper wire
17. Check for continuity between SH-AWD control unit connector terminal A1 and body ground Is there continuity? YES -Replace the rear differential left side case (see «SIDE CASE REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) ) NO -Repair open in the wire between SH-AWD control unit connector terminal A1 and the left solenoid 4P connector

DTC 82-1: Right Search Coil Sensor Malfunction

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

Scheme 91

Scheme 92

Scheme 93

Scheme 94

Scheme 95

Scheme 96

Scheme 97

Scheme 98

1. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
2. Disconnect SH-AWD control unit connector A (20P)
3. Check for continuity between SH-AWD control unit connector terminals A3 and A12 Is there continuity? YES -Go to step 4 NO -Go to step 12
4. Check the REAR DIFFERENTIAL FLUID TEMPERATURE SENSOR in the SH-AWD mode menu DATA LIST The temperature should be above 68°F (20°C) with the HDS before proceeding to the next step If the temperature is below 68°F (20°C), drive the vehicle to warm up the rear differential until the fluid temperature becomes above 68°F (20°C)
5. Measure the resistance between SH-AWD control unit connector terminals A3 and A12 Is there about 2 0 ohms or more? YES -Go to step 6 NO -Go to step 10
6. Disconnect the right solenoid 4P connector
7. Check for continuity between right solenoid 4P connector terminals No 3 and No 4 Is there continuity? YES -Repair short in the wires between SH-AWD control unit connector A and the right solenoid 4P connector NO -Replace the rear differential right side case (see «SIDE CASE REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) )
8. Check for continuity between SH-AWD control unit connector terminal A3 and body ground Is there continuity? YES -Repair short to body ground in the wire between SH-AWD control unit connector terminal A3 and body ground NO -Go to step 9
9. Check the connections at the SH-AWD control unit Are the connections loose or poor? YES -Repair the connections as needed, and recheck NO -Go to step 10
10. Update the SH-AWD control unit with the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), and recheck Does the symptom/indication go away? YES -Troubleshooting is complete NO -Go to step 11
11. Substitute the SH-AWD control unit with a known-good control unit, and recheck Does the symptom/indication go away? YES -Replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ) NO -Replace the rear differential right side case (see «SIDE CASE REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) ) NOTE: If a new SH-AWD control unit was used in place of the known-good control unit and the new control unit will not initialize, replace the rear differential right side case
12. Disconnect the right solenoid 4P connector
13. Connect right solenoid 4P connector terminal No 3 to body ground with a jumper wire
14. Check for continuity between SH-AWD control unit connector terminal A12 and body ground Is there continuity? YES -Go to step 15 NO -Repair open in the wire between SH-AWD control unit connector terminal A12 and the right solenoid 4P connector
15. Remove the jumper wire from right solenoid 4P connector terminal No 3
16. Connect right solenoid 4P connector terminal No 4 to body ground with a jumper wire
17. Check for continuity between SH-AWD control unit connector terminal A3 and body ground Is there continuity? YES -Replace the rear differential right side case (see «SIDE CASE REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) ) NO -Repair open in the wire between SH-AWD control unit connector terminal A3 and the right solenoid 4P connector

DTC 91-1: SH-AWD Control Unit Programming Error

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ) DTC 91-1 is stored when the SH-AWD system update is not completed Do not turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode while updating the SH-AWD system If you do, the SH-AWD system can be damaged

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Do the SH-AWD system update procedure (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) )
3. Check for DTCs with the HDS Is DTC 91-1 indicated? YES -Substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ) NO -Update is complete

The SH-AWD indicator does not go off, and no DTCs are stored

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ) Make sure the No 2-6 (30 A) fuse in the under-hood fuse/relay box is OK Make sure there are no loose connector terminals at the SH-AWD control unit Make sure the charging system and the battery are OK Make sure the PGM-FI system and the A/T system is not in the middle of updating

1. Test the battery (see «BATTERY TEST»(/acura/tl/iv-2008-2011/remont/body-electrical/#battery) ) Charge or replace the battery if necessary
2. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
3. Check the COMPLETE MEMORIZATION in the DATA LIST with the HDS Does the data list show "complete"? YES -Go to step 4 NO -Do the SH-AWD system memorization procedure for each of the following, then go to step 4 SH-AWD differential clutch torque (see «SH-AWD DIFFERENTIAL CLUTCH TORQUE MEMORIZATION»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-differential-clutch-torque-memorization) ) Yaw rate-lateral/longitudinal acceleration neutral position (see «YAW RATE-LATERAL/LONGITUDINAL ACCELERATION NEUTRAL POSITION MEMORIZATION»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__yaw-rate-laterallongitudinal-acceleration-neutral-position-m) ) SH-AWD control unit initialization (see «YAW RATE-LATERAL/LONGITUDINAL ACCELERATION NEUTRAL POSITION MEMORIZATION»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__yaw-rate-laterallongitudinal-acceleration-neutral-position-m) )
4. Check for DTCs in the VSA system with the HDS Are any steering angle sensor DTCs indicated? YES -Go to the indicated DTC's troubleshooting NO -Go to step 5
5. Start the engine
6. Check the SH-AWD indicator value with the HDS Is the SH-AWD indicator value OFF? YES -Go to the gauge control self-diagnostic function (see «SELF-DIAGNOSTIC FUNCTION»(/acura/tl/iv-2008-2011/remont/gauges-instrument-panels/#display-and-gauge-system__self-diagnostic-function) ) NO -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) )

The SH-AWD indicator does not come on

Note. Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Check the SH-AWD indicator Does the SH-AWD indicator come on and go off? YES -Intermittent failure, the system is OK at this time NO -Go to step 3
3. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
4. Disconnect SH-AWD control unit connector A (20P) and connector B (8P)
5. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
6. Check the SH-AWD indicator Does the SH-AWD indicator come on? YES -Update the SH-AWD control unit if it does not have the latest software (see «HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__how-to-troubleshoot-circuits-at-the) ), or substitute a known-good SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ), and recheck If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see «SH-AWD CONTROL UNIT REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-control-unit-replacement) ) NO -Go to the gauge control self-diagnostic function (see «SELF-DIAGNOSTIC FUNCTION»(/acura/tl/iv-2008-2011/remont/gauges-instrument-panels/#display-and-gauge-system__self-diagnostic-function) )

SH-AWD Function Test

Special Tools Required

Torque wrench adapter 070AJ-SJAA101

Direct Electromagnetic Clutch Test

Note. No DTC was detected The transmission is in neutral (M/T) or N (A/T) The SH-AWD control unit had been initialized

Scheme 99

Scheme 100

Scheme 101

1. With the ignition switch in LOCK (0), or the vehicle in the OFF mode, connect the HDS to the DLC (A) located under the driver's side of the dashboard
2. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
3. Make sure the HDS communicates with the vehicle and the SH-AWD control unit If it does not, go to the DLC circuit troubleshooting (see «DLC CIRCUIT TROUBLESHOOTING»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__dlc-circuit-troubleshooting) )
4. Check that the differential fluid temperature is over 68°F (20°C) with the HDS If it is below 68°F (20°C), raise the temperature by driving the vehicle in circles or by constantly turning
5. Raise the vehicle on a lift, and make sure it is securely supported
6. Remove the rear wheels
7. Install the torque wrench adapter on the rear wheel hub
8. Do the Direct Electromagnetic Clutch Test with the HDS
9. Install a torque wrench on the torque wrench adapter as shown. Write down the torque value with the HDS while slowly rotating the rear hub with the torque wrench as shown (Turn the hub no more than 90 degrees in 7 to 10 seconds) NOTE: Use a torque wrench capable of measuring up to 785 N m (80 0 kgf m, 579 lbf ft) such as a commercially available Snap-on torque wrench TE352FUE
10. Enter the torque value into the HDS, and wait for the test to finish If the result shows the clutch driving force is normal, the clutch assembly is OK If the result shows the clutch driving force is abnormal, replace the differential fluid, and retest If the result still shows the clutch driving force is abnormal, replace the right and left differential side cases (see «SIDE CASE REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) )

Scheme 102

1. Park the vehicle on level ground, and turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
2. Use solvent and a brush to wash any oil and dirt off the differential fluid filler plug, and dry them with compressed air
3. Remove the filler plug (A) and the sealing washer (B), then check the condition of the fluid, and make sure the fluid is at the proper level (C)
4. If the level is below the proper level, check for fluid leaks at the differential If a problem is found, fix it before filling the differential with fluid
5. The fluid level must reach up the bottom of the filler plug hole If necessary, add the recommended fluid until it runs out, then reinstall the filler plug with a new sealing washer

Scheme 103

Scheme 104

1. Park the vehicle on level ground, and turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
2. Remove the filler plug (A) and the sealing washer (B)
3. Remove the drain plug (C) and the sealing washer (D), and drain the fluid
4. Reinstall the drain plug with a new sealing washer
5. Refill the recommended fluid until it reaches the bottom of the filler plug hole Fluid Capacity 2.53 L (2.67 US qt) at fluid change 2.77 L (2.93 US qt) at overhaul Recommended fluid Acura ATF-Z1
6. Reinstall the filler plug with a new sealing washer
7. If the maintenance minder required to replace the rear differential fluid, reset the maintenance minder (see «MAINTENANCE MINDER»(/acura/tl/iv-2008-2011/remont/reset-procedures/#maintenance) ), and this procedure is complete. If the maintenance minder did not require to replace the rear differential fluid, go to step 8.
8. With the ignition switch in LOCK (0), or the vehicle in the OFF mode, connect the HDS to the DLC (A) located under the driver's side of the dashboard
9. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
10. Make sure the HDS communicates with the vehicle and the PCM If it does not, go to the DLC circuit troubleshooting (see «DLC CIRCUIT TROUBLESHOOTING»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__dlc-circuit-troubleshooting) )
11. Select GAUGES in the BODY ELECTRICAL with the HDS
12. Select ADJUSTMENT in the GAUGES with the HDS
13. Select MAINTENANCE MINDER in the ADJUSTMENT with the HDS
14. Select RESET in the MAINTENANCE MINDER with the HDS
15. Select MAINTENANCE SUB ITEM 6 RESET with the HDS, and reset the rear differential fluid life

Scheme 105

1. Drain the differential fluid (see «REAR DIFFERENTIAL FLUID INSPECTION AND REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) )
2. Remove the rear differential fluid temperature sensor cover (A) and the rear differential harness bracket D, then disconnect the rear differential fluid temperature sensor 2P connector (B)
3. Remove the rear differential fluid temperature sensor(C)
4. Install the rear differential fluid temperature sensor with a new O-ring (E) in the reverse order of removal
5. Refill the differential fluid (see «REAR DIFFERENTIAL FLUID INSPECTION AND REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) )

SH-AWD Control Unit Replacement

Note. The SH-AWD control unit must be initialized (see YAW RATE-LATERAL/LONGITUDINAL ACCELERATION NEUTRAL POSITION MEMORIZATION ) after replacement, otherwise the SH-AWD system will not function

Scheme 106

1. Remove the trunk front trim panel (see «TRIM REMOVAL/INSTALLATION - TRUNK AREA»(/acura/tl/iv-2008-2011/remont/exteriorinterior-trim/#interior-trim__trim-removalinstallation-trunk-area) )
2. Remove the SH-AWD control unit (A)
3. Disconnect the SH-AWD control unit connectors (B)
4. Install the SH-AWD control unit in the reverse order of removal

Scheme 107

1. Remove the trunk front trim panel (see «TRIM REMOVAL/INSTALLATION - TRUNK AREA»(/acura/tl/iv-2008-2011/remont/exteriorinterior-trim/#interior-trim__trim-removalinstallation-trunk-area) )
2. Remove the SH-AWD relay (A)
3. Install the SH-AWD relay in the reverse order of removal

Scheme 108

Special Tools Required

Driveshaft remover 07AAD-S3VA000

Scheme 109

Scheme 110

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Scheme 112

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Scheme 117

1. Raise the vehicle on a lift
2. Drain the rear differential fluid (see «REAR DIFFERENTIAL FLUID INSPECTION AND REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) )
3. Remove the rear wheels
4. Remove exhaust pipe B and the muffler (see «EXHAUST PIPE AND MUFFLER REPLACEMENT»(/acura/tl/iv-2008-2011/remont/mechanical/#intake-manifold-and-exhaust-system__exhaust-pipe-and-muffler-replacement) )
5. Remove the lower arm A mounting bolts (A) and the lower arm B mounting bolts (B)
6. Disconnect the inboard joints (A) from the rear differential (B) using the driveshaft remover (C) and a hammer
7. Pull the knuckle (A) outward, and separate the rear driveshaft inboard joints (B) from the rear differential
8. Make reference marks (A) across the No 3 propeller shaft (B) and the rear differential companion flange (C) Separate the No 3 propeller shaft from the rear differential NOTE: Suspend the propeller shaft with an appropriate size wire
9. Disconnect the rear differential subharness connectors (A), and remove the harness clips (B)
10. Remove the rear subharness rear bracket bolts (A)
11. Place a transmission jack (A) under the rear differential (B)
12. Remove the rear differential rear mount bolts (C) and the rear differential front mounting bracket nuts (D)
13. Lower the rear differential a little on the transmission jack, then disconnect the breather hose (A)
14. Lower the rear differential on the transmission jack
15. Remove the set ring (A) from the rear differential

Scheme 118

Scheme 119

Scheme 120

Scheme 121

Scheme 122

Scheme 123

Scheme 124

Scheme 125

1. Place the rear differential on a transmission jack
2. Install a new set ring (A) into the groove (B) of the rear differential
3. Raise the rear differential to the appropriate position, then connect the breather hose (A)
4. Raise the rear differential to the mounting level
5. Loosely install new rear differential rear mount bolts (A and B) and new rear differential front mounting bracket nuts (C)
6. Loosen the rear differential front mounting bracket bolts (D)
7. Tighten the rear differential rear mount bolt (A) and the rear differential front mounting bracket nuts (C) to the specified torque
8. Tighten the rear differential rear mount bolt (B) to the specified torque
9. Tighten the rear differential front mounting bracket bolts (D) to the specified torque
10. Install the rear subframe rear bracket bolts (A)
11. Connect the rear differential subharness connectors (A), and install the harness clips (B)
12. Attach the No 3 propeller shaft (A) to the rear differential (B) by aligning the reference marks (C) you made during the removal procedure
13. Apply appropriate grease to the rear driveshaft inboard joints (see step 2 on «REAR DRIVESHAFT INSTALLATION»(/acura/tl/iv-2008-2011/remont/axle-shafts/#drivelineaxle__rear-driveshaft-installation) )
14. Pull the knuckle outward, and insert the rear driveshaft inboard joints (A) into the rear differential (B)
15. Loosely install new lower arm A mounting bolts (A) and new lower arm B mounting bolts (B)
16. Place a floor jack under the lower arm, and raise the suspension to load it with the vehicle's weight
17. Tighten the lower arm A mounting bolt and the lower arm B mounting bolt to the specified torque
18. Install exhaust pipe B and the muffler (see «EXHAUST PIPE AND MUFFLER REPLACEMENT»(/acura/tl/iv-2008-2011/remont/mechanical/#intake-manifold-and-exhaust-system__exhaust-pipe-and-muffler-replacement) )
19. Install the rear wheels
20. Refill the rear differential with the recommended fluid (see «REAR DIFFERENTIAL FLUID INSPECTION AND REPLACEMENT»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) )
21. Test-drive the vehicle

Scheme 126

Side Case Oil Seal Replacement

Special Tools Required

1. Driver 07AAD-STKA100
2. Oil seal driver 07AAD-STKA111
3. Dust seal driver 07AAD-STKA120

Scheme 127

Scheme 128

Scheme 129

Scheme 130

1. Remove the rear differential (see «REAR DIFFERENTIAL REMOVAL»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) )
2. Remove the 40 x 55 x 7.5 mm dust seal (A) using a commercially available tool NOTE: Remove the dust seal with care so you do not damage the inside surface of the side case seal surface
3. Remove the thrust washer
4. To remove the 34.7 x 54 x 9 mm oil seal (A), install the 6 mm screw (B) (P/N 93901-16580) into the maintenance hole (C) of the oil seal as shown, the oil seal has four invisible holes from the surface for maintenance (4 places, 90 degrees apart) Remove the oil seal using pliers (D) and a screw driver (E) as shown NOTE: Do not thread the 6 mm screw into the oil seal more than 5 mm (0.20 in)
5. Install a new 34.7 x 54 x 9 mm oil seal (A) into the rear differential side case (B) using the oil seal driver (C) and the driver (D)
6. Install the thrust washer (A), then install a new 40 x 55 x 7.5 mm dust seal (B) using the dust seal driver (C) and the driver (D)
7. Install the rear differential (see «REAR DIFFERENTIAL INSTALLATION»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) )

Scheme 131

Scheme 132

Scheme 133

Scheme 134

Scheme 135

Scheme 136

Scheme 137

Scheme 138

Scheme 139

1. Remove the rear differential (see «REAR DIFFERENTIAL REMOVAL»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) )
2. Remove the rear differential front mounting brackets (A) from the rear differential (B)
3. Disconnect the rear differential fluid temperature sensor 2P connector (A), then remove the rear differential fluid temperature sensor cover (B), the rear differential fluid temperature sensor (C), and the O-ring (D)
4. Disconnect the left and right solenoid 4P connectors (A)
5. Remove the ground cable bolt (B) and rear differential harness bracket D, then remove the rear differential subharness (C)
6. Remove the rear differential left side case (A), the rear differential right side case (B), and the 10 x 12 mm dowel pins (C) from the rear differential center case (D)
7. Replace the rear differential center case
8. Remove the dirt and oil from the sealing surfaces Apply liquid gasket (P/N 08717-0004, 08718-0001, 08718-0003, or 08718-0009) to the sealing surface Make sure you seal up to the inside edge of the bolt holes to prevent oil leakage NOTE: You must assemble the housings within 5 minutes after applying the liquid gasket If you applied liquid gasket P/N 08718-0012, the component must be installed within 4 minutes If not, the sealing surface must be cleaned, and the liquid gasket reapplied Allow the liquid gasket to cure at least 30 minutes after assembly before filling the differential with fluid Left side case/Right side case
9. Install the 10 x 12 mm dowel pins (A), the rear differential right side case (B), the rear differential left side case (C), and the mounting bolts (D) onto the rear differential center case (E)
10. Tighten the mounting bolts in a crisscross pattern in several steps, then tighten the bolts to the specified torque
11. Install the rear differential subharness (A) and rear differential harness bracket D, and install the ground cable (B)
12. Connect the left arid right solenoid 4P connectors (C)
13. Install the rear differential fluid temperature sensor (A) with a new O-ring (B), and install the rear differential fluid temperature sensor cover (C)
14. Connect the rear differential fluid temperature sensor 2P connector (D)
15. Install the rear differential front mounting brackets (A) with new bolts (B) on the rear differential (C)
16. Install the rear differential (see «REAR DIFFERENTIAL INSTALLATION»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) )

Scheme 140

Scheme 141

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Scheme 156

Scheme 157

Scheme 158

1. Remove the rear differential (see «REAR DIFFERENTIAL REMOVAL»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) )
2. Remove the rear differential front mounting brackets (A) from the rear differential (B)
3. Disconnect the rear differential fluid temperature sensor 2P connector (A), then remove the rear differential fluid temperature sensor cover (B), the rear differential fluid temperature sensor (C), and the O-ring (D)
4. Disconnect the left and right solenoid 4P connectors (A)
5. Remove the ground cable bolt (B) and rear differential harness bracket D, then remove the rear differential subharness (C)
6. Remove the rear differential left side case (A) or the rear differential right side case (D), and the 10x12 mm dowel pins (E) from the rear differential center case (F)
7. Remove rear differential harness bracket B and rear differential harness bracket C
8. Replace the rear differential left side case or the rear differential right side case
9. Remove the ring gear (A), the needle bearing (B), and the 60.2 mm shim (C) from the differential side case (D)
10. Measure the distance (1) between the end of the rear differential side case (A) and the 60.2 mm shim contact area (B) of the planetary gear with a straight edge (C) and a depth gauge (D) Measure at three locations, and average the reading NOTE: Carry out the measurement at normal room temperature Clean all parts thoroughly before measure
11. Measure the distance (2) between the end of the rear differential center case (A) and the ring gear contact area (B) of the tapper roller bearing with a straight edge (C) and a depth gauge (D) Measure at three locations, and average the reading NOTE: Carry out the measurement at normal room temperature Clean all parts thoroughly before measure
12. Measure the distance (3) between the needle bearing (A) and the tapper roller bearing contact area (B) of ring gear with a depth gauge (C) Measure at three locations, and average the reading NOTE: Carry out the measurement at normal room temperature Clean all parts thoroughly before measure Shim Selection Formula
13. Select the proper 60.2 mm shim from the table Follow the example below, and use the measurements you made in step 10 to 12 (Basic Formula) (1) + (2) - ((3) + 0 19)= shim thickness 0.19 mm (0.007 in) middle of the standard clearance Standard Clearance 0.14-0.24 mm (0.006-0.009 in) (For example) (1) = 6.12 mm (0.241 in) (2) = 153 mm (0.602 in) (3) = 19.56 mm (0.770 in) 6.12 + 15.3 - (19.56 + 0.19) = 1.67 mm Select the 1.60 mm shim from the table 60.2 mm shim PART THICKNESS CHART No Thickness A 1 10 mm (0 043 in) B 1 20 mm (0 047 in) C 1 30 mm (0 051 in) D 1 40 mm (0 055 in) E 1 50 mm (0 059 in) F 1 60 mm (0 063 in) G 1 70 mm (0 067 in) H 1 80 mm (0 071 in) I 1 90 mm (0 075 in) J 2 00 mm (0 079 in) K 2 10 mm (0 083 in) L 2 20 mm (0 087 in)
14. Place one strip of plastigage (A) on the 60.2 mm shim contact area (B) of planetary gear Install the 60.2 mm shim (C), the needle bearing (D), and the ring rear (E) Measure at three locations as shown. NOTE: Carry out the measurement at normal room temperature Clean all parts thoroughly before measure
15. Install the 10x12 mm dowel pins (A), the rear differential right side case (B) or the rear differential left side case (C), and the mounting bolts (D) onto the rear differential center case (E)
16. Tighten the mounting bolts in a crisscross pattern in several steps, then tighten the bolts to the specified torque
17. Remove the rear differential left side case (A) or the rear differential right side case (B), and the 10 x 12 mm dowel pins (C) from the rear differential center case (D)
18. Remove the ring gear (A), the needle bearing (B), and the 60 2 mm shim (C) from the differential side case (D)
19. Measure the widest part of the plastigage Measure at three locations, and average the reading If the clearance exceeds the standard, go to step 9 If the clearance is within the standard, go to step 20 Standard Clearance 0.14-0 24 mm (0.006-0.009 in)
20. Install the 60.2 mm shim (A), the needle bearing (B), and the ring gear (C) onto the rear differential side case (D)
21. Remove the dirt and oil from the sealing surfaces Apply liquid gasket (P/N 08717-0004,08718-0001, 08718-0003, or 08718-0009) to the sealing surface Make sure you seal up to the inside edge of the bolt holes to prevent oil leakage NOTE: You must assemble the housings within 5 minutes after applying the liquid gasket If you applied liquid gasket P/N 08718-0012, the component must be installed within 4 minutes If not, the sealing surface must be cleaned, and the liquid gasket reapplied Allow the liquid gasket to cure at least 30 minutes after assembly before filling the differential with fluid Left side case/Right side case
22. Install the 10 x 12 mm dowel pins (A), the rear differential right side case (D) or the rear differential left side case (E), and the mounting bolts (F) onto the rear differential center case (G)
23. Install rear differential harness bracket B and rear differential harness bracket C
24. Tighten the mounting bolts in a crisscross pattern in several steps, then tighten the bolts to the specified torque
25. Install the rear differential subharness (A) and rear differential harness bracket D, and install the ground cable (B)
26. Connect the left and right solenoid 4P connectors (C)
27. Install the rear differential fluid temperature sensor (A) with a new O-ring (B), and install the rear differential fluid temperature sensor cover (C)
28. Connect the rear differential fluid temperature sensor 2P connector (D)
29. Install the rear differential front mounting brackets (A) with new bolts (B) on the rear differential (C)
30. Install the rear differential (see «REAR DIFFERENTIAL INSTALLATION»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential) )
31. Do the SH-AWD differential clutch torque memorization (see «SH-AWD DIFFERENTIAL CLUTCH TORQUE MEMORIZATION»(/acura/tl/iv-2008-2011/remont/differentials-drive-axles/#rear-differential__sh-awd-differential-clutch-torque-memorization) )

See also:
• DLC CIRCUIT TROUBLESHOOTING
• TRIM REMOVAL/INSTALLATION - TRUNK AREA
• YAW RATE-LATERAL ACCELERATION SENSOR REPLACEMENT
• WHEEL ALIGNMENT
• VSA SENSOR NEUTRAL POSITION MEMORIZATION
• STEERING ANGLE SENSOR REPLACEMENT
• POWER RELAY TEST
• BRAKE SYSTEM INSPECTION AND TEST
• BATTERY TEST
• SELF-DIAGNOSTIC FUNCTION
• MAINTENANCE MINDER
• EXHAUST PIPE AND MUFFLER REPLACEMENT
• REAR DRIVESHAFT INSTALLATION
• SYMPTOM TROUBLESHOOTING
• YAW RATE-LATERAL/LONGITUDINAL ACCELERATION NEUTRAL POSITION MEMORIZATION
• SH-AWD DIFFERENTIAL CLUTCH TORQUE MEMORIZATION
• DTC 15-1: LONGITUDINAL ACCELERATION SENSOR MALFUNCTION
• DTC 16-3: STEERING ANGLE SENSOR NEUTRAL POSITION INCORRECT
• DTC 33-2, 33-3: YAW RATE SENSOR MALFUNCTION
• DTC 41-1: F-CAN MALFUNCTION (LOST COMMUNICATION WITH POWERTRAIN CONTROL MODULE (PCM))
• DTC 41-2: F-CAN MALFUNCTION (LOST COMMUNICATION WITH VSA MODULATOR-CONTROL UNIT)
• DTC 41-4: F-CAN MALFUNCTION (LOST COMMUNICATION WITH A/T CONTROL SYSTEM)
• DTC 41-5: F-CAN MALFUNCTION (LOST COMMUNICATION WITH YAW RATE-LATERAL/LONGITUDINAL ACCELERATION SENSOR)
• DTC 41-6: F-CAN MALFUNCTION (LOST COMMUNICATION WITH STEERING ANGLE SENSOR)
• DTC 42-1: DIFFERENTIAL FLUID TEMPERATURE SENSOR (SHORT TO POWER)
• DTC 42-2: DIFFERENTIAL FLUID TEMPERATURE SENSOR (OPEN/GND SHORT)
• DTC 43-1: DIFFERENTIAL FLUID TEMPERATURE SENSOR MALFUNCTION
• DTC 44-11: SH-AWD CONTROL UNIT
• DTC 44-12: SH-AWD RELAY STUCK ON
• DTC 44-32: SH-AWD CONTROL UNIT POWER SUPPLY STUCK ON; DTC 44-41: SH-AWD CONTROL UNIT POWER SUPPLY STUCK OFF
• DTC 44-50: SH-AWD CONTROL UNIT POWER SUPPLY VOLTAGE LOW
• DTC 49-1: SH-AWD CONTROL UNIT (PG LINE OPEN)
• DTC 52-3: LEFT CLUTCH ELECTROMAGNETIC COIL CURRENT MALFUNCTION
• DTC 53-1, 53-3: LEFT CLUTCH ELECTROMAGNETIC COIL (OPEN)
• DTC 53-2: LEFT CLUTCH ELECTROMAGNETIC COIL (SHORT)
• DTC 56-3: RIGHT CLUTCH ELECTROMAGNETIC COIL CURRENT MALFUNCTION
• DTC 57-1, 57-3: RIGHT CLUTCH ELECTROMAGNETIC COIL (OPEN)
• DTC 57-2: RIGHT CLUTCH ELECTROMAGNETIC COIL (SHORT)
• DTC 77-1: THE FUNCTIONAL ABNORMALITIES OF FUEL AND EMISSIONS
• DTC 77-4: THE FUNCTIONAL ABNORMALITIES OF AUTOMATIC TRANSMISSION
• DTC 81-1: LEFT SEARCH COIL SENSOR MALFUNCTION
• DTC 82-1: RIGHT SEARCH COIL SENSOR MALFUNCTION
• DTC 91-1: SH-AWD CONTROL UNIT PROGRAMMING ERROR
• THE SH-AWD INDICATOR DOES NOT COME ON
• SIDE CASE OIL SEAL REPLACEMENT
• HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT
• SH-AWD CONTROL UNIT REPLACEMENT
• SH-AWD FUNCTION TEST