Rear Differential Acura MDX I

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VTM-4 Indicator

The VTM-4 indicator comes on under certain conditions even if the 4WD 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 8 Volts or rises above 16 Volts. After the VTM-4 indicator comes on, it stays on until you turn the ignition switch off.

Diagnostic Trouble Code (DTC)

1. The VTM-4 control unit can memorize up to seven different DTCs. The system displays the DTCs by blinking the VTM-4 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 EEPROM (non-volatile memory). Therefore, the memorized DTCs are not cleared when the battery is disconnected or the VTM-4 control unit is disconnected.
4. If there is a problem in the central processing unit (CPU) of the VTM-4 control unit, the VTM-4 indicator comes on, but no DTC is memorized.

Self-diagnosis

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

1. Turns the VTM-4 indicator on.
2. Memorizes the DTC.
3. Stops 4WD control and puts the vehicle back in 2WD (FWD).
4. Reduces engine torque to suit the driving conditions when the abnormality was detected.

Initialization of the VTM-4 Control Unit

Whenever the VTM-4 control unit is replaced, it must be initialized to make the 4WD system function.

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1. With the ignition switch OFF, connect the HDS to the 16P DLC (A) behind the driver's dashboard lower cover.
2. Turn the ignition switch ON (II), and follow the prompts on the HDS screen. NOTE: See the HDS help menu for specific instruction.

How to Check for Diagnostic Trouble Codes (DTCs)

When the VTM-4 control unit senses an abnormality in the input or output systems, the VTM-4 indicator in the gauge assembly will usually come on, and the malfunction indicator lamp (MIL), the D5 indicator, and/ or the ABS indicator may also come on.

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1. With the ignition switch OFF, connect the HDS to the 16P DLC (A) behind the driver's dashboard lower cover.
2. Turn the ignition switch ON (II), and follow the prompts on the HDS to display the DTC(s) on the screen. After determining the DTC(s), refer to the DTC Troubleshooting . NOTE: See the HDS help menu for specific instruction.
3. If there are fuel and emission DTCs, A/T DTCs, and vehicle stability assist (VSA) DTC's at the same time, troubleshoot the fuel and emission DTCs first.
4. After recording the DTCs, clear all DTCs.
5. Test-drive the vehicle for several minutes in 4WD mode, and check for DTCs. If the DTC returns, refer to the DTC Troubleshooting . 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 VTM-4 Control Unit

Special Tools Required

Backprobe set 07SAZ-001000A (two required)

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1. Remove the front mounting bolts from the right third row seat, and fold the seat cushion back.
2. Remove the cover from the right rear side trim panel to gain access to the VTM-4 control unit (see «VTM-4 CONTROL UNIT REPLACEMENT»(/acura/mdx/i-2000-2006/remont/differentials-drive-axles/#rear-differential__vtm-4-control-unit-replacement) ).
3. Inspect the circuit on the VTM-4 control unit according to the DTC Troubleshooting using the special tools 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 the 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.

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1. With the ignition switch OFF, connect the HDS to the 16P DLC (A) behind the driver's dashboard lower cover.
2. Turn the ignition switch ON (II), and follow the prompts on the HDS screen to clear the DTC(s). NOTE: See the HDS help menu for specific instruction.

How to End a Troubleshooting Session (required after any troubleshooting)

1. Turn the ignition switch OFF.
2. Clear the DTCs from the VTM-4 control unit memory.
3. Disconnect the HDS from the 16P DLC.
4. Verify that the problem has been repaired by test-driving the vehicle for several minutes in 4WD mode.

DTC Troubleshooting Index

DTC TROUBLESHOOTING INDEX

Symptom Troubleshooting Index

SYMPTOM TROUBLESHOOTING INDEX

System Description

This vehicle is equipped with a rear differential system called the variable torque management 4WD (VTM-4) system. The VTM-4 control unit controls the currents flowing through electromagnetic coils to engage and disengage the right and left clutches in the rear differential assembly.

The operation of the VTM-4 system consists of the following functions

1. Vehicle acceleration torque control (VATC)
2. Limited slip differential (LSD)
3. Lock control

These functions automatically combine to distribute driving torque between the front and rear wheels when the vehicle accelerates or when the wheels are slipping. When the vehicle speed is about 18 mph (30 km/h) or below, and the transmission is in R, 2, or 1, the system will manually engage the rear differential clutches when the VTM-4 LOCK switch is pressed. By design, in lock mode, the torque is reduced gradually at speeds above 6 mph (10 km/h) to minimize the load on the 4WD system.

The VTM-4 control unit has a fail-safe function, a self-diagnosis function, and a provision to communicate with the HDS.

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1. VATC Control The torque to be delivered to the rear wheels is calculated based on the acceleration of the vehicle calculated in the VTM-4 control unit.
2. LSD Control The torque to be delivered to the rear wheels is calculated based on the differences in speed and acceleration between the front and rear wheels.
3. LOCK Control Rear differential clutch lock control is done by pushing the VTM-4 LOCK switch manually when the shift lever is in R, 1, or 2.

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VTM-4 Control Unit Inputs and Outputs

The VTM-4 control unit terminal voltage and measuring conditions for the 4WD control system are shown.

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TERMINAL CONDITION SPECIFICATION

The VTM-4 control unit terminal voltage and measuring conditions for the 4WD control system are shown.

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TERMINAL CONDITION SPECIFICATION

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1. Clear the DTCs (see «HOW TO CLEAR THE VTM-4 CONTROL UNIT MEMORY»(/acura/mdx/i-2000-2006/remont/differentials-drive-axles/#rear-differential) ).
2. Test-drive the vehicle, and watch the VTM-4 indicator. Does the VTM-4 indicator come on? YES - Go to step 3. NO - The system is OK at this time.
3. Watch the VSA indicator. Does the VSA indicator come on? YES - Check the VSA system for DTCs (see «GENERAL TROUBLESHOOTING INFORMATION»(/acura/mdx/i-2000-2006/remont/anti-locktraction-control/#vsa-vehicle-stability-assist-system-components) ). NO - Go to step 4.
4. Raise the vehicle, and make sure it is securely supported.
5. Spin the rear wheels by hand, and check for rear brake drag. Are the rear brakes dragging? YES - Repair cause of rear brake drag, and retest. NO - Go to step 6.
6. Turn the ignition switch ON (II).
7. Measure the voltage between the A7 and A9 terminals of the VTM-4 control unit and body ground while rotating the appropriate wheel (1 rotation/second). TERMINAL CONDITION SPECIFICATION DTC Appropriate Terminal 21 (Left-front) A9 22 (Right-front) A7 Is there 2 V to 3 V? YES - Go to step 13 . NO - Go to step 8.
8. Turn the ignition switch OFF.
9. Disconnect the VTM-4 control unit and the VSA modulator-control unit connectors.
10. Check the same terminal of VTM-4 control unit connector A (22P) for continuity to body ground. Is there continuity? YES - Repair short to ground in the wire between the A7 and/or A9 terminals of the VTM-4 control unit and the VSA modulator-control unit. NO - Go to step 11.
11. Connect the same terminals of VTM-4 control unit connector A (22P) to body ground with the jumper wires.
12. Check for continuity between the VSA modulator-control unit connector terminals and body ground. TERMINAL CONDITION SPECIFICATION Appropriate wheel Appropriate Terminal VTM-4 Control Unit VSA modulator Right-front A7 26 Left-front A9 42 Is there continuity? YES - Go to step 13. NO - Repair open in the wire between the A7 and/or A9 terminals of the VTM-4 control unit and the VSA modulator-control unit.
13. Check for loose terminal fit in the VTM-4 control unit and the VSA modulator-control unit connectors. If it is normal, replace the VTM-4 control unit. Test-drive the vehicle, and watch the VTM-4 indicator. Does the VTM-4 indicator come on? YES - Replace the VSA modulator-control unit. NO - The system is OK at this time.

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1. Clear the DTCs (see «HOW TO CLEAR THE VTM-4 CONTROL UNIT MEMORY»(/acura/mdx/i-2000-2006/remont/differentials-drive-axles/#rear-differential) ).
2. Start the engine, shift the transmission into D. Drive the vehicle at speeds over 25 mph (40 km/h), while keeping the engine rpm below 2,500 for at least 30 seconds. Watch the VTM-4 indicator. NOTE: Be careful not to overheat the rear differential clutch system.
3. Watch the VTM-4 indicator. Does the VTM-4 indicator come on? YES - Go to step 4. NO - The system is OK at this time.
4. Watch the ABS indicator. Does the ABS indicator come on? YES -Check the VSA system for DTCs (see «GENERAL TROUBLESHOOTING INFORMATION»(/acura/mdx/i-2000-2006/remont/anti-locktraction-control/#vsa-vehicle-stability-assist-system-components) ). NO - Go to step 5.
5. Raise the vehicle, and make sure it is securely supported.
6. Spin the rear wheels by hand, and check for rear brake drag. Are the rear brakes dragging? YES - Repair cause of rear brake drag, and retest. NO - Go to step 7.
7. Turn the ignition switch ON (II).
8. Measure the voltage between the A3 and A5 terminal of the VTM-4 control unit and body ground while rotating the appropriate wheel (1 rotation/ second). TERMINAL CONDITION SPECIFICATION DTC Appropriate Terminal 23 (Left-rear) A5 24 (Right-rear) A3 Is there 2 V to 3 V? YES - Go to step 15 . NO - Go to step 9.
9. Turn the ignition switch OFF.
10. Disconnect the VTM-4 control unit and the VSA modulator-control unit connectors.
11. Check the same terminal of VTM-4 control unit connector A (22P) for continuity to body ground. Is there continuity? YES - Repair short to ground in the wire between the A3 and/or A5 terminals of the VTM-4 control unit and the VSA modulator-control unit. NO - Go to step 12.
12. Connect the same terminals of VTM-4 control unit connector A (22P) to body ground with the jumper wires.
13. Check for continuity between the VSA modulator-control unit connector terminals and body ground. TERMINAL CONDITION SPECIFICATION Appropriate wheel Appropriate Terminal VTM-4 Control Unit VSA modulator Right-rear A3 41 Left-rear A5 9 Is there continuity? YES - Go to step 14. NO - Repair open in the wire between the A3 and/or A5 terminals of the VTM-4 control unit and the VSA modulator-control unit.
14. Check for loose terminal fit in the VTM-4 control unit and the VSA modulator-control unit connectors. If it is normal, replace the VTM-4 control unit, then go to step 15.
15. Start the engine, shift the transmission into D. Drive the vehicle at speeds over 25 mph (40 km/h), while keeping the engine rpm below 2,500 for at least 30 seconds. Watch the VTM-4 indicator. NOTE: Be careful not to overheat the rear differential clutch system. Does the VTM-4 indicator come on? YES - Replace the VSA modulator-control unit. NO - The system is OK at this time.

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1. Clear the DTCs (see «HOW TO CLEAR THE VTM-4 CONTROL UNIT MEMORY»(/acura/mdx/i-2000-2006/remont/differentials-drive-axles/#rear-differential) ).
2. Test-drive the vehicle, and watch the VTM-4 indicator. Does the VTM-4 indicator come on? YES - Go to step 3. NO - The system is OK at this time.
3. Watch the VSA indicator. Does the VSA indicator come on? YES - Check the VSA system for DTCs (see «GENERAL TROUBLESHOOTING INFORMATION»(/acura/mdx/i-2000-2006/remont/anti-locktraction-control/#vsa-vehicle-stability-assist-system-components) ). NO - Go to step 4.
4. Raise the vehicle, and make sure it is securely supported.
5. Turn the ignition switch ON (II).
6. Measure the voltage between the A3, A5, A7, and A9 terminals of the VTM-4 control unit and body ground while rotating the appropriate wheel one rotation a second. TERMINAL CONDITION SPECIFICATION Appropriate wheel Appropriate Terminal Left-front A9 Right-front A7 Left-rear A5 Right-rear A3 Are all four readings 2 V to 3 V? YES - Check for loose terminal fit in the VTM-4 control unit. If it is normal, replace the VTM-4 control unit. NO - Check for loose wires or poor connections between the VTM-4 control unit and the VSA modulator-control unit. If it is normal, replace the VSA modulator-control unit.

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1. Clear the DTCs (see «HOW TO CLEAR THE VTM-4 CONTROL UNIT MEMORY»(/acura/mdx/i-2000-2006/remont/differentials-drive-axles/#rear-differential) ).
2. Test-drive the vehicle, and watch the VTM-4 indicator. Does the VTM-4 indicator come on? YES - Go to step 3. NO - The system is OK at this time.
3. Watch the MIL. Does the MIL come on? YES - Check the fuel and emission system for DTCs (see «GENERAL TROUBLESHOOTING INFORMATION»(/acura/mdx/i-2000-2006/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems) ). NO - Go to step 4.
4. Disconnect connector A (22P) from the VTM-4 control unit.
5. Measure the voltage between the A12 terminal of the VTM-4 control unit and body ground with the engine running. VOLTAGE CONDITION SPECIFICATION Condition Voltage Ignition switch ON (II) Above 8 V Engine running at 1,000 rpm 5-8 V Is the voltage correct? YES - Go to step 13 . NO - Go to step 6.
6. Turn the ignition switch OFF.
7. Disconnect PCM connector B (56P) and gauge assembly connector A (30P).
8. Turn the ignition switch ON (II).
9. Measure the voltage between the A12 terminal of the VTM-4 control unit and body ground. Is there voltage? YES - Repair short to power in the wire between the A12 terminal of the VTM-4 control unit and the B27 terminal of the PCM. NO - Go to step 10.
10. Turn the ignition switch OFF.
11. Check for continuity between the A12 terminal of the VTM-4 control unit and body ground. Is there continuity? YES - Repair short to ground in the wire between the A12 terminal of the VTM-4 control unit, the B27 terminal of the PCM, and the A13 terminal of the gauge assembly. NO - Go to step 12.
12. Connect the A12 terminal of the VTM-4 control unit connector A (22P) to body ground with the jumper wire, then check for continuity between the B27 terminal of the PCM, the A13 terminal of the gauge assembly, and body ground. 2003 model: 2004-2006 models: Is there continuity? YES - Go to step 13. NO - Repair open in the wire between the A12 terminal of the VTM-4 control unit, the B27 terminal of the PCM, and the A13 terminal of the gauge assembly.
13. Check for loose terminal fit in the VTM-4 control unit, PCM connectors, and the gauge assembly connectors. If it is normal, replace the VTM-4 control unit. Test-drive the vehicle, and watch the VTM-4 indicator. Does the VTM-4 indicator come on? YES - Replace the PCM or gauge assembly. NO - The system is OK at this time.

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1. Clear the DTC (see «HOW TO CLEAR THE VTM-4 CONTROL UNIT MEMORY»(/acura/mdx/i-2000-2006/remont/differentials-drive-axles/#rear-differential) ).
2. Test-drive the vehicle, and watch the VTM-4 indicator. Does the VTM-4 indicator come on? YES - Go to step 3. NO - The system is OK at this time.
3. Connect the HDS to the 16P Data Link Connector (DLC), and check for a PCM/VSA system DTC. Is there a DTC? YES - Troubleshoot the PCM/VSA system for the cause of the DTC. NO - Go to step 4.
4. Disconnect connector A (22P) from the VTM-4 control unit, connector B (56P) from the PCM, the 47P connector from the VSA modulator-control unit, and connector A (20P) from the navigation unit.
5. Turn the ignition switch ON (II).
6. Measure the voltage between the A11 terminal of the VTM-4 control unit and body ground. Is there voltage? YES - Repair short to power in the wire between the A11 terminal of the VTM-4 control unit and the B16 terminal of the PCM, the 14 terminal of the VSA modulator-control unit, the A8 terminal of the navigation unit. NO - Go to step 7.
7. Turn the ignition switch OFF.
8. Check for continuity between the A11 terminal of the VTM-4 control unit and body ground. Is there continuity? YES - Repair short to ground in the wire between the A11 terminal of the VTM-4 control unit and the B16 terminal of the PCM, the 14 terminal of the VSA modulator-control unit, the A8 terminal of the navigation unit. NO - Go to step 9.
9. Connect the A11 terminal of the VTM-4 control unit connector A (22P) to body ground with a jumper wire, then check for continuity between the B16 terminal of the PCM, the 14 terminal of the VSA modulator-control unit, the A8 terminal of the navigation unit and body ground. Is there continuity? YES - Go to step 10. NO - Repair open in the wire between the A11 terminal of the VTM-4 control unit and B16 terminal of the PCM, the 14 terminal of the VSA modulator-control unit, the A8 terminal of the navigation unit.
10. Disconnect the A (22P) connector from the VTM-4 control unit, the B (56P) connector from the PCM, the 47P connector from the VSA modulator-control unit, and the A (20P) connector from the navigation unit.
11. Turn the ignition switch ON (II).
12. Measure the voltage between the A22 terminal of the VTM-4 control unit and body ground. Is there voltage? YES - Repair short to power in the wire between the A22 terminal of the VTM-4 control unit and the B15 terminal of the PCM, the 30 terminal of the VSA modulator-control unit, the A18 terminal of the navigation unit. NO - Go to step 13.
13. Turn the ignition switch OFF.
14. Check for continuity between the A22 terminal of the VTM-4 control unit and body ground. Is there continuity? YES - Repair short to ground in the wire between the A22 terminal of the VTM-4 control unit and the B15 terminal of the PCM, the 30 terminal of the VSA modulator-control unit, the A18 terminal of the navigation unit. NO - Go to step 15.
15. Connect the A22 terminal of the VTM-4 control unit connector A (22P) to body ground with a jumper wire, then check for continuity between the B15 terminal of the PCM, the 30 terminal of the VSA modulator-control unit, the A18 terminal of the navigation unit and body ground. Is there continuity? YES - Go to step 16. NO - Repair open in the wire between the A22 terminal of the VTM-4 control unit and B15 terminal of the PCM, the 30 terminal of the VSA modulator-control unit, the A18 terminal of the navigation unit.
16. Check for loose terminal fit in the VTM-4 control unit, PCM, VSA, navigation connectors. If it is normal, replace the VTM-4 control unit. Test-drive the vehicle, and watch the VTM-4 indicator. Does the VTM-4 indicator come on? YES - Go to step 17. NO - The system is OK at this time.
17. Watch the ABS indicator. Does the ABS indicator come on? YES - Check the VSA system. NO - Go to step 18.
18. Connect the HDS to the 16P Data Link Connector (DLC), and check for the PCM system DTC. Is there the DTC? YES - Check the PCM system. NO - Check the navigation system.

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1. Clear the DTCs (see «HOW TO CLEAR THE VTM-4 CONTROL UNIT MEMORY»(/acura/mdx/i-2000-2006/remont/differentials-drive-axles/#rear-differential) ).
2. Test-drive the vehicle, and watch the VTM-4 indicator. Does the VTM-4 indicator come on? YES - Go to step 3. NO - The system is OK at this time.
3. Turn the ignition switch OFF.
4. Remove the wire harness cover from the rear differential.
5. Disconnect the 2P connector from the differential oil temperature sensor, then measure the resistance of the differential oil temperature sensor. OIL TEMPERATURE SENSOR SPECIFICATION Oil temperature Resistance 32 °F (0 °C) 5.82 kohm to 7.26 kohm 86 °F (30 °C) 1.53 kohm to 1.83 kohm 212°F(100°C) 148 ohm to 162 ohm 284°F(140°C) 52 ohm to 61 ohm Is the resistance correct? YES - Go to step 6. NO - Replace the differential oil temperature sensor.
6. Disconnect connector A (22P) from the VTM-4 control unit.
7. Turn the ignition switch ON (II).
8. Measure the voltage between the A13 and A15 terminals of the VTM-4 control unit and body ground. Is there voltage? YES - Repair short to power in the wire between the A13 or A15 terminals of the VTM-4 control unit and the differential oil temperature sensor. NO - Go to step 9.
9. Turn the ignition switch OFF.
10. Check for continuity between the A13 and A15 terminals of the VTM-4 control unit and body ground. Is there continuity? YES - Repair short to ground in the wire between the A13 or A15 terminals of the VTM-4 control unit and the differential oil temperature sensor. NO - Go to step 11.
11. Connect the differential oil temperature sensor connector terminals to body ground with jumper wires, then check for continuity between the A13 and A15 terminals of the VTM-4 control unit and body ground. Is there continuity? YES - Check for loose terminal fit in the VTM-4 control unit and the differential oil temperature sensor connectors. If it is normal, replace the VTM-4 control unit. NO - Repair open in the wire between the A13 or A15 terminals of the VTM-4 control unit and the differential oil temperature sensor.

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1. Clear the DTCs (see «HOW TO CLEAR THE VTM-4 CONTROL UNIT MEMORY»(/acura/mdx/i-2000-2006/remont/differentials-drive-axles/#rear-differential) ).
2. Test-drive the vehicle, and watch the VTM-4 indicator. Does the VTM-4 indicator come on? YES - Go to step 3. NO - The system is OK at this time.
3. Turn the ignition switch OFF with the VTM-4 control unit still connected, measure the voltage between the A4 and B7 terminals of the VTM-4 control unit and body ground with the ignition switch ON (II), and after the engine starts. TERMINAL CONDITION SPECIFICATION Condition B7 (PWR) A4 (FSR) Ignition switch ON (II) Below 3 V Battery voltage Engine start Battery voltage Below 1 V Is the voltage correct? YES - Go to step 15 . NO - Go to step 4.
4. Turn the ignition switch OFF.
5. Remove the VTM-4 relay, and test it (see «POWER RELAY TEST»(/acura/mdx/i-2000-2006/remont/body-electrical/#relays__power-relay-test) ). Is the VTM-4 relay OK? YES - Go to step 6. NO - Replace the VTM-4 relay.
6. Turn the ignition switch ON (II) with the VTM-4 relay removed.
7. Measure the voltage between the No. 1 and No. 5 terminals of the VTM-4 relay 5P connector and body ground. Is there battery voltage? YES - Go to step 8. NO - 2003 model: Check for blown No. 92 (7.5 A) fuse in the auxiliary fuse box or No. 6 (15 A) fuse in the driver's underdash fuse/relay box. 2004-2006 models: Check for blown No. 9 (10 A) fuse in the driver's underdash fuse/relay box. If the fuses are OK, repair open in the wire between the auxiliary fuse box or the driver's underdash fuse/relay box and the VTM-4 relay.
8. Turn the ignition switch OFF.
9. Disconnect connector A (22P) and connector B (12P) from the VTM-4 control unit.
10. Turn the ignition switch ON (II).
11. Measure the voltage between the A4 and B7 terminals of the VTM-4 control unit and body ground. Is there voltage? YES - Repair short to power in the wire between the A4 or B7 terminals of the VTM-4 control unit and the VTM-4 relay. NO - Go to step 12.
12. Turn the ignition switch OFF.
13. Check for continuity between the A4 and B7 terminals of the VTM-4 control unit and body ground. Is there continuity? YES - Repair short to ground in the wire between the A4 or B7 terminals of the VTM-4 control unit and the VTM-4 relay. NO - Go to step 14.
14. Check for continuity between the B7 terminal of the VTM-4 control unit and the No. 2 terminal of the VTM-4 relay, and between the A4 terminal of the VTM-4 control unit and the No. 3 terminal of the VTM-4 relay. Is there continuity? YES - Go to step 15. NO - Repair open in the wire between A4 or B7 terminals of the VTM-4 control unit and the VTM-4 relay.
15. Check for loose terminal fit in the VTM-4 control unit and the VTM-4 relay connectors. If it is normal, test-drive the vehicle, and watch the VTM-4 indicator. Does the VTM-4 indicator come on? YES - Replace the VTM-4 control unit. NO - The system is OK at this time.

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1. Clear the DTCs (see «HOW TO CLEAR THE VTM-4 CONTROL UNIT MEMORY»(/acura/mdx/i-2000-2006/remont/differentials-drive-axles/#rear-differential) ).
2. Test-drive the vehicle, and watch the VTM-4 indicator. Does the VTM-4 indicator come on? YES - Go to step 3. NO - The system is OK at this time.
3. Turn the ignition switch OFF.
4. Disconnect the left clutch electromagnetic coil 2P connector on the differential. Then measure the resistance between the No. 1 and No. 2 terminals of the left clutch electromagnetic coil connector. Is there 1 ohm to 3 ohm? YES - Go to step 5. NO - Replace the rear differential assembly.
5. Measure the resistance between the No. 1 terminal of the left clutch electromagnetic coil and differential carrier assembly. Is there 50 Mohm or more? YES - Go to step 6. NO - Replace the rear differential assembly.
6. Disconnect the B (12P) connector from the VTM-4 control unit.
7. Turn the ignition switch ON (II).
8. Measure the voltage between the B1 and B2 terminals of the VTM-4 control unit and body ground. Is there voltage? YES - Repair short to power in the wire between the B1 or B2 terminals of the VTM-4 control unit and the left clutch electromagnetic coil. NO - Go to step 9.
9. Turn the ignition switch OFF.
10. Check for continuity between the B1 and B2 terminals of the VTM-4 control unit and body ground. Is there continuity? YES - Repair short to ground in the wire between the B1 or B2 terminals of the VTM-4 control unit and the left clutch electromagnetic coil. NO - Go to step 11.
11. Connect a jumper wire between the No. 1 and No. 2 terminals of the 2P connector of the left clutch electromagnetic coil. Then check for continuity between the B1 and B2 terminals of the VTM-4 control unit. Is there continuity? YES - Do the troubleshooting for the right clutch electromagnetic coil (see «DTC 53-2,55-1,56-1,57-1,58-1: RIGHT CLUTCH ELECTROMAGNETIC COIL»(/acura/mdx/i-2000-2006/remont/differentials-drive-axles/#rear-differential) ). If it is normal, replace the VTM-4 control unit. NO - Repair open in the wire between the B1 or B2 terminals of the VTM-4 control unit and the left clutch electromagnetic coil.

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1. Clear the DTCs (see «HOW TO CLEAR THE VTM-4 CONTROL UNIT MEMORY»(/acura/mdx/i-2000-2006/remont/differentials-drive-axles/#rear-differential) ).
2. Test-drive the vehicle, and watch the VTM-4 indicator. Does the VTM-4 indicator come on? YES - Go to step 3. NO - The system is OK at this time.
3. Turn the ignition switch OFF.
4. Disconnect the right clutch electromagnetic coil 6P connector on the differential. Then measure the resistance between the No. 3 and No. 6 terminals of the right clutch electromagnetic coil 6P connector. Is there 10 ohm to 3 ohm ? YES - Go to step 5. NO - Replace the rear differential assembly.
5. Measure the resistance between the No. 3 terminal and the differential carrier assembly. Is there 50 Mohm or more? YES - Go to step 6. NO - Replace the rear differential assembly.
6. Disconnect the B (12P) connector from the VTM-4 control unit.
7. Turn the ignition switch ON (II).
8. Measure the voltage between the B3 and B4 terminals of the VTM-4 control unit and body ground. Is there voltage? YES - Repair short to power in the wire between the B3 or B4 terminals of the VTM-4 control unit and the right clutch electromagnetic coil. NO - Go to step 9.
9. Turn the ignition switch OFF.
10. Check for continuity between the B3 and B4 terminals of the VTM-4 control unit and body ground. Is there continuity? YES - Repair short to ground in the wire between the B3 or B4 terminals of the VTM-4 control unit and the right clutch electromagnetic coil. NO - Go to step 11.
11. Connect a jumper between the No. 3 and No. 6 terminals of the right clutch electromagnetic coil 6P connector. Then check for continuity between the B3 and B4 terminals of the VTM-4 control unit. Is there continuity? YES - Do the troubleshooting for the left clutch electromagnetic coil (see «DTC 51-1,52-1,53-1,53-2,54-1: LEFT CLUTCH ELECTROMAGNETIC COIL»(/acura/mdx/i-2000-2006/remont/differentials-drive-axles/#rear-differential) ). If it is normal, replace the VTM-4 control unit. NO - Repair open in the wire between the B3 or B4 terminals of the VTM-4 control unit and the right clutch electromagnetic coil.

DTC 59-1: Right/Left Clutch Electromagnetic Coil Power Supply

1. Clear the DTCs (see «HOW TO CLEAR THE VTM-4 CONTROL UNIT MEMORY»(/acura/mdx/i-2000-2006/remont/differentials-drive-axles/#rear-differential) ).
2. Test-drive the vehicle, and watch the VTM-4 indicator. Does the VTM-4 indicator come on? YES - Go to step 3. NO - The system is OK at this time.
3. Check the battery. Is the specified battery installed, and is it fully charged? YES - Go to step 4. NO - Replace the battery.
4. Watch the charging system indicator. Does the charging system indicator come on with the ignition switch ON (II), and after the engine starts, does the indicator go off? YES - Check for loose terminal fit in the VTM-4 control unit connectors. If it is normal, replace the VTM-4 control unit. NO - Check the charging system.

DTC 73-1: MAP (Manifold Absolute Pressure) Sensor, or PCM

1. Clear the DTCs (see «HOW TO CLEAR THE VTM-4 CONTROL UNIT MEMORY»(/acura/mdx/i-2000-2006/remont/differentials-drive-axles/#rear-differential) ).
2. Test-drive the vehicle, and watch the VTM-4 indicator. Does the VTM-4 indicator come on? YES - Go to step 3. NO - The system is OK at this time.
3. Watch the MIL. Does the MIL come on? YES - Check the Fuel and Emissions system for DTCs (see «GENERAL TROUBLESHOOTING INFORMATION»(/acura/mdx/i-2000-2006/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems) ). NO - Check for loose terminal fit in the VTM-4 control unit and the PCM connectors. If it is normal, replace the VTM-4 control unit.

Scheme 64

Scheme 65

Scheme 66

Scheme 67

1. Clear the DTCs (see «HOW TO CLEAR THE VTM-4 CONTROL UNIT MEMORY»(/acura/mdx/i-2000-2006/remont/differentials-drive-axles/#rear-differential) ).
2. Start the engine, shift the transmission into D. Drive the vehicle at speeds over 25 mph (40 km/h), while keeping the engine rpm below 2,500 for at least 30 seconds. Watch the VTM-4 indicator. NOTE: Be careful not to overheat the rear differential clutch system.
3. Watch the VTM-4 indicator. Does the VTM-4 indicator come on? YES - Go to step 4. NO - The system is OK at this time.
4. Watch the VSA indicator. Does the VSA indicator come on? YES - Check the VSA system for DTCs (see «GENERAL TROUBLESHOOTING INFORMATION»(/acura/mdx/i-2000-2006/remont/anti-locktraction-control/#vsa-vehicle-stability-assist-system-components) ). NO - Go to step 5.
5. Raise the vehicle, and make sure it is securely supported.
6. Spin the rear wheels by hand, and check for rear brake drag. Are the rear brakes dragging? YES - Repair cause of rear brake drag, and retest. NO - Go to step 7.
7. Turn the ignition switch ON (II).
8. Measure the voltage between the A3 and A5 terminals of the VTM-4 control unit and body ground while rotating the appropriate wheel (1 rotation/second). TERMINAL CONDITION SPECIFICATION DTC Appropriate Terminal 23 (Left-rear) A5 24 (Right-rear) A3 Is there 2 V to 3 V? YES - Go to step 15 . NO - Go to step 9.
9. Turn the ignition switch OFF.
10. Disconnect the VTM-4 control unit and the VSA modulator-control unit connectors.
11. Check the A3 and A5 terminals of the VTM-4 control unit connector A (22P) for continuity to body ground. Is there continuity? YES - Repair short to ground in the wire between the A3 and/or A5 terminals of the VTM-4 control unit and the VSA modulator-control unit. NO - Go to step 12.
12. Connect the same terminals of VTM-4 control unit connector A (22P) to body ground with the jumper wires.
13. Check for continuity between the VSA modulator-control unit connector terminals and body ground. TERMINAL CONDITION SPECIFICATION Appropriate wheel Appropriate Terminal VTM-4 Control Unit VSA modulator Right-rear A3 41 Left-rear A5 9 Is there continuity? YES - Go to step 14. NO - Repair the open in the wire between the A3 and/or A5 terminals of the VTM-4 control unit and the VSA modulator-control unit.
14. Check for loose terminal fit in the VTM-4 control unit and the VSA modulator-control unit connectors. If it is normal, replace the VTM-4 control unit, then go to step 15.
15. Start the engine, shift the transmission into D. Drive the vehicle at speeds over 25 mph (40 km/h), while keeping the engine rpm below 2,500 for at least 30 seconds. Watch the VTM-4 indicator. NOTE: Be careful not to overheat the rear differential clutch system. Does the VTM-4 indicator come on? YES - Replace the VSA modulator-control unit. NO - The system is OK at this time.

DTC 77-1: PCM

Check the PCM for DTCs. Fix the PCM DTCs before troubleshooting DTC 77.

1. Clear the DTCs (see «HOW TO CLEAR THE VTM-4 CONTROL UNIT MEMORY»(/acura/mdx/i-2000-2006/remont/differentials-drive-axles/#rear-differential) ).
2. Test-drive the vehicle, and watch the VTM-4 indicator. Does the VTM-4 indicator come on? YES - Go to step 3. NO - The system is OK at this time.
3. Replace the PCM. Test-drive the vehicle, and watch the VTM-4 indicator. Does the VTM-4 indicator come on? YES - Check for loose terminal fit in the VTM-4 control unit. If it is normal, replace the VTM-4 control unit. NO - The system is OK at this time.

DTC 78-1: VTM-4 Control Unit

1. Clear the DTC (see «HOW TO CLEAR THE VTM-4 CONTROL UNIT MEMORY»(/acura/mdx/i-2000-2006/remont/differentials-drive-axles/#rear-differential) ).
2. Test-drive the vehicle, and watch the VTM-4 indicator. Does the VTM-4 indicator come on? YES - Go to step 3. NO - The system is OK at this time.
3. Check the battery. Is the specified battery installed, and is it fully charged? YES - Go to step 4. NO - Replace the battery.
4. Watch the charging system indicator. Does the charging system indicator come on with ignition switch ON (II), and after the engine starts, does the indicator go off? YES - Go to step 5. NO - Check the charging system.
5. Check for installation of any aftermarket CB or Ham radios which may cause an RF signal interference. Is there an aftermarket radio installed? YES - Disconnect the aftermarket radio, and retest. NO - Check for loose terminal fit in the VTM-4 control unit connectors. If it is normal, replace the VTM-4 control unit.

Scheme 68

Scheme 69

1. Check the No. 9 (10 A) fuse in the driver's underdash fuse/relay box. Is the fuse OK? YES - Go to step 2. NO - Replace the fuse, and recheck.
2. Reinitializes the VTM-4 control unit, and watch the VTM-4 indicator (see «INITIALIZATION OF THE VTM-4 CONTROL UNIT»(/acura/mdx/i-2000-2006/remont/differentials-drive-axles/#rear-differential__initialization-of-the-vtm-4-control-unit) ). Does the VTM-4 indicator come on and stay on? YES - Go to step 3. NO - The system is OK at this time.
3. Turn the ignition switch OFF.
4. Measure the voltage between the A1 and A10 terminals of the VTM-4 control unit, and between the A1 and B12 terminals of the VTM-4 control unit. Is there battery voltage? YES - Go to step 5. NO - Repair open in the wire between A1 terminal of the VTM-4 control unit and the driver's underdash fuse/relay box, or repair open in the wire between A10 or B12 terminals of the VTM-4 control unit and body ground.
5. Turn the ignition switch OFF.
6. Disconnect the VTM-4 control unit and the gauge assembly connectors.
7. Check for continuity between the A14 and B11 terminals of the VTM-4 control unit and body ground. Is there continuity? YES - Repair short to ground in the wire between the A14 or B11 terminals of the VTM-4 control unit and the gauge assembly. NO - Go to step 8.
8. Reconnect the gauge assembly connectors only, then turn the ignition switch ON (II). Does the VTM-4 indicator come on? YES - Replace the gauge assembly. NO - Check for loose terminal fit in VTM-4 connectors. If it is normal, replace the VTM-4 control unit.

Scheme 70

Scheme 71

Scheme 72

Scheme 73

1. Turn the ignition switch ON (II), and check for operation of all gauge assembly indicators. Do the indicators come on? YES - Go to step 2. NO - Check for open or short in the power and ground circuits in the gauge assembly. 2003 model (see «CIRCUIT DIAGRAM»(/acura/mdx/i-2000-2006/remont/gauges-instrument-panels/#gauges) ) 2004-2006 models (see «'04-06 MODELS»(/acura/mdx/i-2000-2006/remont/gauges-instrument-panels/#gauges) )
2. Disconnect the A (22P) and B (12P) connectors from the VTM-4 control unit.
3. Turn the ignition switch ON (II).
4. Connect the A14 or B11 terminals of the VTM-4 control unit to body ground with a jumper wire, and watch the VTM-4 indicator. Does the VTM-4 indicator come on? YES - Check for loose terminal fit in the VTM-4 control unit connectors. If it is normal, replace the VTM-4 control unit. NO - Go to step 5.
5. Turn the ignition switch OFF.
6. Disconnect connector A (30P) from the gauge assembly.
7. Connect the A20 terminal of the gauge assembly to body ground with a jumper wire, then check for continuity between the A14 and B11 terminals of the VTM-4 control unit and body ground. 2003 model: 2004-2006 models: Is there continuity? YES - Check for a blown bulb in the VTM-4 indicator or a problem in the gauge assembly. NO - Repair open in the wire between the A20 terminal of the gauge assembly and the driver's underdash fuse/relay box.

The VTM-4 LOCK indicator does not come on when the VTM-4 LOCK button is pressed

Note. The VTM-4 LOCK indicator will only come on when the engine is running and the transmission is in R, 1, or 2 before the switch is pressed.

Scheme 74

Scheme 75

Scheme 76

Scheme 77

Scheme 78

1. Check the No. 9 (10 A) fuse in the driver's underdash fuse/relay box. Is the fuse OK? YES - Go to step 2. NO - Replace the fuse, and recheck.
2. Turn the ignition switch ON (II), and watch the VTM-4 LOCK indicator. Does the VTM-4 LOCK indicator come on with the ignition switch ON (II), and does it go off 4 seconds later? YES - Go to step 3. NO - Go to step 10 .
3. Start the engine, and move the shift lever to R, 1, and 2, then watch the VTM-4 LOCK indicator. Does the VTM-4 LOCK indicator come on when the VTM-4 LOCK button is pushed? YES - The system is OK at this time. NO - Go to step 4.
4. Check for an A/T system DTC. Is there a DTC? YES - Troubleshoot the A/T system for the cause of the DTC. NO - Go to step 5.
5. Turn the ignition switch OFF.
6. Disconnect connector A (22P) from the VTM-4 control unit.
7. Turn the ignition switch ON (II).
8. Connect a voltmeter between the A8 terminal of the VTM-4 control unit and body ground. Is there battery voltage when the VTM-4 LOCK button is pushed? YES - Check for loose terminal fit in the VTM-4 control unit connector. If it is normal, replace the VTM-4 control unit. NO - Go to step 9.
9. Test the VTM-4 LOCK button (see «DIFFERENTIAL OIL TEMPERATURE SENSOR REPLACEMENT»(/acura/mdx/i-2000-2006/remont/differentials-drive-axles/#rear-differential) ). Is the VTM-4 LOCK button OK? YES - Repair open in the wire between the VTM-4 LOCK button and the VTM-4 control unit. NO - Replace the VTM-4 LOCK button.
10. Connect the A16 terminal of the VTM-4 control unit to body ground with a jumper wire, and watch the VTM-4 LOCK indicator. Does the VTM-4 LOCK indicator come on? YES - Check for loose terminal fit in the VTM-4 control unit connector. If it is normal, replace the VTM-4 control unit. NO - Go to step 11.
11. Turn the ignition button OFF.
12. Remove the VTM-4 LOCK button.
13. Connect the No. 1 terminal of the VTM-4 LOCK button 6P connector to body ground with a jumper wire. Check for continuity between the A16 terminal of the VTM-4 control unit and body ground. Is there continuity? YES - Go to step 14. NO - Repair open in the wire between the A16 terminal of the VTM-4 control unit and the VTM-4 LOCK button.
14. Turn the ignition switch ON (II).
15. Measure the voltage between the No. 2 terminal of the VTM-4 LOCK button 6P connector and body ground.

Is there battery voltage?

1. YES - Replace the VTM-4 LOCK indicator bulb.
2. NO - Repair open in the wire between the No. 2 terminal of the VTM-4 LOCK button 6P connector and the driver's underdash fuse/relay box.

Scheme 79

1. Disconnect connector A (22P) from the VTM-4 control unit.
2. Turn the ignition switch ON (II), and watch the VTM-4 LOCK indicator. Does the VTM-4 LOCK indicator come on with the ignition switch ON (II)? YES - Go to step 3. NO - Check for loose terminal fit in the VTM-4 control unit connectors. If it is normal, replace the VTM-4 control unit.
3. Turn the ignition switch OFF.
4. Disconnect the VTM-4 LOCK button connector.
5. Check for continuity between the A16 terminal of the VTM-4 control unit and body ground. Is there continuity? YES - Repair short to ground in the wire between the A16 terminal of the VTM-4 control unit and the VTM-4 LOCK button. NO - Replace the VTM-4 LOCK button.

Scheme 80

Scheme 81

Scheme 82

Scheme 83

1. Disconnect connector A (22P) from the VTM-4 control unit.
2. Turn the ignition switch ON (II).
3. Connect the A16 terminal of the VTM-4 control unit to body ground with a jumper wire, and watch the VTM-4 LOCK indicator. Does the VTM-4 LOCK indicator come on? YES - Check for loose terminal fit in the VTM-4 control unit connectors. If it is normal, replace the VTM-4 control unit. NO - Go to step 4.
4. Turn the ignition switch OFF.
5. Remove the VTM-4 LOCK button.
6. Connect the No. 1 terminal of the VTM-4 LOCK button 6P connector to body ground with a jumper wire. Check for continuity between the A16 terminal of the VTM-4 control unit connector and body ground. Is there continuity? YES - Go to step 7. NO - Repair open in the wire between the A16 terminal of the VTM-4 control unit and the VTM-4 LOCK button.
7. Turn the ignition switch ON (II).
8. Measure the voltage between the No. 2 terminal of the VTM-4 LOCK button 6P connector and body ground. Is there battery voltage? YES - Replace the VTM-4 LOCK indicator bulb. NO - Repair open in the wire between the No. 2 terminal of the VTM-4 LOCK button 6P connector and the driver's underdash fuse/relay box.

Scheme 84

1. With the vehicle on level ground, inspect the differential fluid with the ignition switch OFF.
2. Remove the oil filler plug (A) and sealing washer (B), then check the condition of the fluid, and make sure the fluid is at the proper level (C).
3. The fluid level must be up to the fill hole. If it is below the hole, add the recommended fluid until it runs out, then reinstall the oil filler plug with a new sealing washer.
4. If the differential fluid is dirty, remove the drain plug (D) and sealing washer, then drain the fluid.
5. Clean the drain plug, then reinstall with a new washer, and refill the differential with the recommended fluid to the proper level. Fluid capacity: 2.64 L (2.79 US.qt) at oil change Recommended fluid: VTM-4 Differential Fluid
6. Reinstall the oil filler plug with a new washer.

Differential Function Test

Note. Before doing the Differential Function Test, make sure these conditions are met

1. No DTCs are detected
2. The engine is OFF
3. The VTM-4 control unit is initialized

1. Connect the HDS to the DLC.
2. Turn the ignition switch ON, and confirm that the temperature of the differential oil is between 20 °C (68 °F) and 60 °C (140 °F) with the HDS.
3. Turn the ignition switch OFF with the shift lever in P.
4. Lift up the vehicle so all four wheel are off the ground (see «LIFT AND SUPPORT POINTS»(/acura/mdx/i-2000-2006/remont/hoistjack/#general-information__lift-and-support-points) ).
5. Remove the rear wheels (see «KNUCKLE/HUB/WHEEL BEARING REPLACEMENT»(/acura/mdx/i-2000-2006/remont/suspension-rear/#rear-suspension) ).
6. Release the parking brake.
7. Turn the ignition switch ON.
8. Select MISCELLANEOUS TEST, then select the LEFT CLUTCH ELECTROMAGNETIC COIL TEST with the HDS, and follow the screen prompts. If the results are NORMAL, the left clutch is OK, go to step 9. If the results are ABNORMAL, replace the rear differential.
9. Select MISCELLANEOUS TEST, then select the RIGHT CLUTCH ELECTROMAGNETIC COIL TEST with the HDS, and follow the screen prompts. If the results are NORMAL, the right clutch is OK. If the results are ABNORMAL, replace the rear differential.

Scheme 85

1. Remove the wire harness cover (A), then disconnect the differential oil temperature sensor 2P connector (B).
2. Remove the differential oil temperature sensor (C).
3. Install the differential oil temperature sensor in the reverse order of removal, with a new O-ring (D).

Scheme 86

Scheme 87

1. Remove the instrument panel (see «INSTRUMENT PANEL REMOVAL/INSTALLATION»(/acura/mdx/i-2000-2006/remont/exteriorinterior-trim/#dashboard__instrument-panel-removalinstallation) ).
2. Disconnect the 6P connector (A) from the VTM-4 LOCK button (B), then remove the two screws and the switch.
3. Check for continuity between the terminals in each button position according to the table. If the button fails any continuity check, replace the button.

VTM-4 Control Unit Replacement

Note. The VTM-4 control unit must be initialized (see INITIALIZATION OF THE VTM-4 CONTROL UNIT ) after replacement, otherwise the 4WD system will not function.

Scheme 88

1. Remove the front mounting bolts from the right third row seat, and fold the seat cushion back (see «THIRD ROW SEAT REMOVAL/INSTALLATION»(/acura/mdx/i-2000-2006/remont/seats/#seats__third-row-seat-removalinstallation) ).
2. Remove the cover (A) from the right rear side trim panel to gain access to the VTM-4 control unit (B).
3. Remove the three bolts (C) from the VTM-4 control unit.
4. Disconnect the VTM-4 control unit connectors.
5. Install the VTM-4 control unit in the reverse order of removal.

Scheme 89

1. Remove the right rear side trim panel (see «TRIM REMOVAL/INSTALLATION - REAR SIDE LOWER AREA»(/acura/mdx/i-2000-2006/remont/exteriorinterior-trim/#interior-trim__trim-removalinstallation-rear-side-lower) ).
2. Remove the VTM-4 relay (A).
3. Install the VTM-4 relay in the reverse order of removal.

Scheme 90

Scheme 91

Special Tools Required

Driveshaft remover 07AAD-S3VA000

Scheme 92

Scheme 93

Scheme 94

1. Drain the differential fluid (see «DIFFERENTIAL FLUID INSPECTION AND REPLACEMENT»(/acura/mdx/i-2000-2006/remont/differentials-drive-axles/#rear-differential) ).
2. Make a reference mark across the propeller shaft, the transmission, and the rear differential, then remove the propeller shaft (see «PROPELLER SHAFT REMOVAL»(/acura/mdx/i-2000-2006/remont/axle-shafts/#drivelineaxle) ).
3. Remove the left upper arm bolt, then remove the upper arm from the vehicle (see «UPPER ARM REMOVAL/INSTALLATION»(/acura/mdx/i-2000-2006/remont/suspension-rear/#rear-suspension__upper-arm-removalinstallation) ).
4. Remove the left rear damper (see «DAMPER REMOVAL AND INSTALLATION»(/acura/mdx/i-2000-2006/remont/suspension-rear/#rear-suspension) ).
5. Using the special tool, pry out both inboard joints (A) from the differential (B). NOTE: This is a prying tool, do not strike it with a hammer.
6. Place a transmission jack under the rear differential (A).
7. Disconnect the 6P (B) and 2P (C) connectors, then remove the mounting bolts (D) and washer (E).
8. Lower the rear differential a little on the transmission jack, then remove the rear driveshaft (A) from the rear differential.
9. Disconnect the breather tube (B) from the rear differential.
10. Lower the rear differential on the transmission jack.

Backlash Inspection

Note. Connecting battery voltage to either the right or left clutch electromagnet coils for more than 3 minutes will damage the rear differential.

Scheme 95

1. Install the left rear driveshaft, then connect the battery power to the No. 1 terminal of the left clutch electromagnetic coil 2P connector (A) and ground to the No. 2 terminal.
2. Check the backlash of the companion flange (B) with a dial indicator (C). Standard: 1.23-2.38 mm (0.048-0.094 in.)
3. If the backlash is out of standard, replace the rear differential.

Scheme 96

Scheme 97

Scheme 98

1. Raise the rear differential a little on the transmission jack, then connect the breather tube (A) to the rear differential.
2. Apply multipurpose grease to the splines of the rear driveshaft (B) (see step 1 ), then install the rear driveshaft to the rear differential.
3. Raise the rear differential to the mounting level, then install the mounting bolts (A) and washer (B).
4. Connect the 6P (C) and 2P (D) connectors.
5. Install the rear damper (see «DAMPER REMOVAL AND INSTALLATION»(/acura/mdx/i-2000-2006/remont/suspension-rear/#rear-suspension) ).
6. Install the upper arm and the upper arm bolt to the vehicle (see «UPPER ARM REMOVAL/INSTALLATION»(/acura/mdx/i-2000-2006/remont/suspension-rear/#rear-suspension__upper-arm-removalinstallation) ).
7. Install the new rear differential (A) onto the propeller shaft (B), by aligning the reference marks (C). Make sure you use new mounting bolts.
8. Attach the propeller shaft to the transmission and the rear differential by aligning the reference marks (see «PROPELLER SHAFT INSTALLATION»(/acura/mdx/i-2000-2006/remont/axle-shafts/#drivelineaxle) ).
9. Refill the differential with recommended fluid (see «DIFFERENTIAL FLUID INSPECTION AND REPLACEMENT»(/acura/mdx/i-2000-2006/remont/differentials-drive-axles/#rear-differential) ).

See also:
• GENERAL TROUBLESHOOTING INFORMATION
• GENERAL TROUBLESHOOTING INFORMATION
• POWER RELAY TEST
• CIRCUIT DIAGRAM
• LIFT AND SUPPORT POINTS
• KNUCKLE/HUB/WHEEL BEARING REPLACEMENT
• INSTRUMENT PANEL REMOVAL/INSTALLATION
• THIRD ROW SEAT REMOVAL/INSTALLATION
• TRIM REMOVAL/INSTALLATION - REAR SIDE LOWER AREA
• PROPELLER SHAFT REMOVAL
• UPPER ARM REMOVAL/INSTALLATION
• VTM-4 CONTROL UNIT REPLACEMENT
• 21-1
• 59-1
• 73-1
• 77-1
• 78-1
• THE VTM-4 LOCK INDICATOR DOES NOT COME ON WHEN THE VTM-4 LOCK BUTTON IS PRESSED
• INITIALIZATION OF THE VTM-4 CONTROL UNIT