Adaptive Cruise Control System Acura RL II

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Adaptive Cruise Control (ACC) Indicator (Amber)

When the ACC system is OK, the ACC indicator comes on for about 2 seconds after turning the ignition switch ON (II), then it goes off.

When the ACC system detects a problem while in operation, the ACC system stops control, and the ACC indicator comes on and stays on.

Note. The ACC system is communicating with the PCM, the VSA system, and the gauge control module by F-CAN. If a connected unit malfunctions, the ACC system does not operate. In this case, both the ACC indicator and the connected unit indicator come on and stay on (except the gauge control module).

Scheme 8

Adaptive Cruise Control (ACC) Activation Indicator (Green)

If the ACC system is normal, the indicator comes on when the ACC switch is ON, and goes off when the ACC switch is OFF. If the ACC system malfunctions, the indicator color changes from green to amber.

Self-diagnostic Function

The ACC system has a self-diagnostic function. If the self-diagnostic function detects a malfunction, the ACC system stops control, turns on the ACC indicator (Amber), and stores DTCs.

Multi-information Display (MID) Indication

If the ACC system is normal, the ACC indicates its operation on the multi-information display (MID) when the ACC switch is ON.

Adaptive Cruise Control (ACC) Unit

The ACC unit uses input from the millimeter wave radar unit to control the vehicle's speed and brakes to maintain a constant distance between the vehicle and other moving vehicles directly ahead.

Millimeter Wave Radar

The millimeter wave radar unit recognizes the position of the moving vehicle ahead and detects the two vehicles speed differential.

The ACC unit receives this information from the millimeter wave radar unit.

The millimeter wave radar unit also detects its own errors, and it signals the ACC unit if an error is detected.

CAN Communication

The ACC unit is on the F-CAN, and it communicates with other units (AcuraLink, gauge control module, navigation, PCM, SH-AWD, SRS, and VSA) via the F-CAN.

If the ACC unit detects a communication error or a malfunction in another connected unit, the ACC system will not operate even though it is OK.

In this case, both the ACC indicator and the related unit indicator will come on and stay on.

Millimeter Wave Radar Aiming

If the millimeter wave radar unit is removed or replaced, do the millimeter wave radar aiming procedure. If the aiming is incomplete, the ACC indicator comes on.

Scheme 9

1. With the ignition switch OFF, connect the HDS to the data link connector (DLC) (A) under the left side of the dashboard.
2. Turn the ignition switch ON (II).
3. Make sure the HDS communicates with the vehicle and the ACC unit. If it does not communicate, troubleshoot the DLC circuit (see «DLC CIRCUIT TROUBLESHOOTING»(/acura/rl/ii-2004-2008/remont/testing-diagnostics/#pgm-fi-system) ).
4. Follow the prompts on the HDS to display the DTC(s) on the screen. After determining the DTC, refer to the «DTC TROUBLESHOOTING»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) . NOTE: See the HDS Help menu for specific instructions. Before troubleshooting, always verify that you have the latest version of the HDS software.

How to Clear DTCs

Note. You cannot clear the DTCs manually.

1. With the ignition switch OFF, connect the HDS to the data link connector (DLC) (A) under the left side of the dashboard.
2. Turn the ignition switch ON (II).
3. Make sure the HDS communicates with the vehicle and the ACC unit. If it does not communicate, troubleshoot the DLC circuit (see «DLC CIRCUIT TROUBLESHOOTING»(/acura/rl/ii-2004-2008/remont/testing-diagnostics/#pgm-fi-system) ).
4. Clear the DTC(s) by following the screen prompts on the HDS. NOTE: See the for specific instructions.

DTC Troubleshooting Index

DTC TROUBLESHOOTING INDEX

Symptom Troubleshooting Index

Note. The adaptive cruise control system is cancelled when the VSA system is activated.

SYMPTOM TROUBLESHOOTING INDEX

System Description

The adaptive cruise control (ACC) system automatically controls the vehicle speed, within the set speed, to maintain a safe distance to the vehicle ahead.

Operation Criteria

1. When there is no vehicle ahead, the ACC maintains the set speed.
2. When there is a vehicle ahead, the ACC maintains a set distance within the set speed.
3. If the vehicle ahead pulls over out of the way, the ACC accelerates the vehicle to the set speed and maintains that speed.
4. The ACC measures the distance from the vehicle ahead using the millimeter wave radar unit, and it determines if the target vehicle driving ahead is in the same lane by using inputs from the vehicle speed sensor and the yaw rate sensor.
5. If the ACC detects a slow vehicle and the distance to the vehicle ahead is closing, the vehicle, speed is reduced primarily by closing the throttle, and additional slowing is accomplished by using the brakes. If the vehicle ahead is too close, an alarm sounds.
6. If a slower vehicle ahead accelerates, the throttle is opened to accelerate the vehicle (up to the set speed) to maintain the following distance.

Scheme 10

1. Radar detection: Max. 0.06 mile (100 m) ahead in a 16 degree field of view
2. Vehicle operating speed: 25-90 mph (40-145 km/h)

The ACC unit obtains information from external sensors and switches that are connected to their respective control units.

Adaptive Cruise Control Operation Range

Scheme 11

1. Setting speed range is 25-90 mph (20-145 km/h)
2. Setting following distance from vehicle ahead is 1.0-2.0 seconds
3. Maximum deceleration is 0.30 G

Millimeter Wave Radar Unit

The millimeter wave radar unit is installed on the front bulkhead on the main bracket. The main bracket allows the radar unit angle to be adjusted ± 3 degrees vertically and horizontally (the horizontal adjustment includes the ± 2 degrees of auto-aiming margin) by moving the main bracket adjusters. The millimeter wave radar unit has these functions

Scheme 12

Basic distance function

The millimeter wave radar unit radiates 76-77 GHz radar waves within a range of 328 ft (100 m) ahead and 16 degrees horizontally and 3.9 degrees vertically, and it receives the reflected waves. In doing so, it can calculate the distance from the vehicle ahead, the relative speed (the difference of speed between two vehicles) and position, and output the data to the ACC unit.

Aiming function

The millimeter wave radar unit has a horizontal auto-aiming function and runs auto aiming in the range of ± 2 degrees in accordance with the directions from the ACC unit. It also has a mechanical adjustment mechanism that covers the range that the auto-aiming cannot.

Self-diagnosis function

The millimeter wave radar unit has a self-diagnostic function, and it outputs the self-diagnostic information to the ACC unit.

Sensitivity-lowering detection function

When the detecting performance of the radar is deteriorated by dirt, dust, or other contaminants, it signals the condition malfunction to the ACC unit until the performance is restored.

Adjuster-misalignment detection function

When more than ± 5 degrees of adjuster misalignment is detected while driving, it signals the condition to the ACC unit.

Brake Fluid Pressure Sensor

The brake fluid pressure sensors are installed in the right and left sides of the brake line 4-way joint. The brake fluid pressure is converted to a signal (voltage value) and is output to the ACC unit. The ACC unit is always monitoring the ACC brake operation and the brake pressure controlled by the signal sent from the brake fluid pressure sensor.

Scheme 13

Gauge Control Module

When the ACC system is working, the ACC activation indicator (green) comes on and the working condition is displayed on the multi-information display (MID). If a system problem is detected, the ACC indicator (amber) comes on and it is displayed on the MID.

Scheme 14

Adaptive Cruise Control (ACC) System Related Switches

The switches are installed on the right side of the steering wheel for ease of operation.

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How to Troubleshoot DTCs

Check the DTCs with the HDS. Make a copy of the freeze data, then clear the DTC.

Before troubleshooting, check and note these items

1. Ask the client about the conditions when the problem occurred, and try to reproduce the same conditions for troubleshooting.
2. If the symptom does not appear and the ACC indicator does not come on during the test-drive, but troubleshooting is done based on the DTC, check for poor connections or loose terminals at all connectors related to the circuit that you are troubleshooting.
3. After the troubleshooting or repairs are done, clear the DTCs, and test-drive the vehicle under the same conditions as when the DTC was originally set. Make sure the ACC indicator does not come on.
4. The ACC system sometimes stops control because of the environment (weather, road conditions, driving conditions, etc.). A DTC may be stored in these cases.

DTCs that may be stored even when the system is normal

DTC 83: ACC does not come on

Performance of the millimeter wave radar unit is not stable. (Driving behind a target vehicle that caused unstable reception.)

DTC 84: ACC indicator does not come on

Target vehicle comes closer than the millimeter wave radar unit detecting limits (The target vehicle brakes suddenly, etc.).

DTC 85: ACC indicator does not come on

Extensive driving on a rough road or a winding road, or VSA system detects a problem.

DTC 86: ACC indicator does not come on

Abnormal tire pressure, flat tire

DTC 87: ACC indicator does not come on

ACC brakes work continuously, or ACC brake control is temporarily prohibited by a communication line error detected between the ACC unit and VSA modulator-control unit.

DTC 88: ACC indicator does not come on

Millimeter wave radar unit temperature is high, millimeter wave radar unit supply voltage is too low, or out of detection condition.

DTC 89: ACC indicator does not come on

Front wheel spin

DTC 91: ACC indicator does not come on

Vehicle skidded, spun out, or there was an abrupt steering wheel movements.

DTC 93: ACC indicator does not come on

Target vehicle comes closer than the millimeter wave radar detecting limits.

DTC 94: ACC indicator does not come on

Rear tire problem (different diameter of tires, flat tire, or large air pressure differential).

DTC 95: ACC indicator does not come on

Power supply voltage is too high.

DTC 96: ACC indicator does not come on

Power supply voltage is too low.

DTC 99: ACC indicator does not come on

Detects acceleration or deceleration that is out of the normal system operating range.

DTC 100: ACC indicator does not come on

CMBS initial check is incomplete.

DTC 101: ACC indicator does not come on

Rear wheel locked (driving with the parking brake applied, or the parking brake stuck).

DTC 107: ACC indicator comes on

Millimeter wave radar unit aiming is incomplete.

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TERMINALS DESCRIPTION

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TERMINALS DESCRIPTION

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DTC 10: Vehicle Speed Signal Error

Note. If DTC 110 and DTC 111 are stored at the same time as DTC 10, troubleshoot DTC 110 and DTC 111 first, then recheck for DTC 10.

1. Check for PGM-FI system DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated PGM-FI system DTC(s). NO - Go to step 2.
2. Check for VSA system DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated VSA system DTC(s). NO - Go to step 3.
3. Clear the DTCs with the HDS.
4. Test-drive the vehicle at 28 mph (45 km/h) or more, and watch the ACC indicator. Does the ACC indicator come on? YES - Go to step 5. NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.
5. Check for DTCs with the HDS. Is DTC 10 indicated? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Troubleshoot the indicated DTC.

DTC 11: Left Rear Wheel Sensor Signal Error

Note. If DTC 112 is stored at the same time as DTC 11, troubleshoot DTC 112 first, then recheck for DTC 11.

1. Check for VSA system DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated VSA system DTC(s). NO - Go to step 2.
2. Clear the DTCs with the HDS.
3. Test-drive the vehicle at 28 mph (45 km/h) or more.
4. Test-drive and watch the adaptive cruise control (ACC) indicator. Does the ACC indicator come on? YES - Go to step 5. NO - Intermittent failure, the. system is OK at this time. Check for loose or poor connections.
5. Check for DTCs with the HDS.

Is DTC 11 indicated?

YES - Check for loose or poor connections. If OK, replace the ACC unit (see DISTANCE SWITCH TEST ).

NO - Troubleshoot the indicated DTC.

DTC 12: Right Rear Wheel Sensor Signal Error

Note. If DTC 112 is stored at the same time as DTC 12, troubleshoot DTC 112 first, then recheck for DTC 12.

1. Check for VSA system DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated VSA system DTC(s). NO - Go to step 2.
2. Clear the DTCs with the HDS.
3. Test-drive the vehicle at 28 mph (45 km/h) or more.
4. Test-drive and watch the adaptive cruise control (ACC) indicator. Does the ACC indicator come on? YES - Go to step 5. NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.
5. Check for DTCs with the HDS. Is DTC 12 indicated? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Troubleshoot the indicated DTC.

DTC 13: Left Front Wheel Sensor Signal Error

Note. If DTC 112 is stored at the same time as DTC 13, troubleshoot DTC 112 first, then recheck for DTC 13.

1. Check for VSA system DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated VSA system DTC(s). NO - Go to step 2.
2. Clear the DTCs with the HDS.
3. Test-drive the vehicle at 28 mph (45 km/h) or more, and watch the adaptive cruise control (ACC) indicator. Does the ACC indicator come on? YES - Go to step 4. NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.
4. Check for DTCs with the HDS. Is DTC 13 indicated? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Troubleshoot the indicated DTC.

DTC 14: Right Front Wheel Sensor Signal Error

Note. If DTC 112 is stored at the same time as DTC 14, troubleshoot DTC 112 first, then recheck for DTC 14.

1. Check for VSA system DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated VSA system DTC(s). NO - Go to step 2.
2. Clear the DTCs with the HDS.
3. Test-drive the vehicle at 28 mph (45 km/h) or more, and watch the adaptive cruise control (ACC) indicator. Does the ACC indicator come on? YES - Go to step 4. NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.
4. Check for DTCs with the HDS. Is DTC 14 indicated? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Troubleshoot the indicated DTC.

DTC 21: Yaw Rate Sensor Error; DTC 22: Yaw Rate Sensor Center Position Revision Value Error

Note. If DTC 112 is stored at the same time as DTC 21, troubleshoot DTC 112 first, then recheck for DTC 21 or DTC 22.

1. Check for VSA system DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated VSA system DTC(s). NO - Go to step 2.
2. Clear the DTCs with the HDS.
3. Turn the ignition switch ON (II).
4. Watch the adaptive cruise control (ACC) indicator. Does the ACC indicator come on? YES - Go to step 5. NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.
5. Check for DTCs with the HDS. Is DTC 21 or DTC 22 indicated? YES - Go to step 6. NO - Troubleshoot the indicated DTC.
6. Check YAW RATE S with the HDS. Is about 2.5 V indicated? YES - The yaw rate sensor signal is OK, check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Go to VSA system troubleshooting (see «ABS/VSA INDICATOR»(/acura/rl/ii-2004-2008/remont/anti-locktraction-control/#vsa-vehicle-stability-assist-system__absvsa-indicator) ).

DTC 23: Yaw Rate-Lateral/Longitudinal Acceleration Sensor Gain Error

Note. If DTC 112 is stored at the same time as DTC 23, troubleshoot DTC 112 first, then recheck for DTC 23.

1. Check for VSA system DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated VSA system DTC(s). NO - Go to step 2.
2. Clear the DTCs with the HDS.
3. Start the engine.
4. Test-drive the vehicle at 28 mph (45 km/h) or more, and watch the adaptive cruise control (ACC) indicator. Does the ACC indicator come on? YES - Go to step 5. NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.
5. Check for DTCs with the HDS. Is DTC 23 indicated? YES - Go to step 6. NO - Troubleshoot the indicated DTC.
6. Test-drive in a straight line at 12.4 mph (20 km/h) or more, and check YAW RATE S with the HDS. Is about 2.5 V indicated? YES - Go to step 7. NO - Go to VSA system troubleshooting (see «ABS/VSA INDICATOR»(/acura/rl/ii-2004-2008/remont/anti-locktraction-control/#vsa-vehicle-stability-assist-system__absvsa-indicator) ).
7. Turn right at 12.4 mph (20 km/h) or more, and check YAW RATE S with the HDS. Does the voltage increase from 2.5 V? YES - Go to step 8. NO - Go to VSA system troubleshooting (see «ABS/VSA INDICATOR»(/acura/rl/ii-2004-2008/remont/anti-locktraction-control/#vsa-vehicle-stability-assist-system__absvsa-indicator) ).
8. Turn left at 12.4 mph (20 km/h) or more, and check YAW RATE S with the HDS. Does the voltage decrease from 2.5 V? YES - The yaw rate-lateral/longitudinal acceleration sensor signal is OK, check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Go to VSA system troubleshooting (see «ABS/VSA INDICATOR»(/acura/rl/ii-2004-2008/remont/anti-locktraction-control/#vsa-vehicle-stability-assist-system__absvsa-indicator) ).

DTC 25: Yaw Rate-Lateral/Longitudinal Acceleration Sensor Stabilizing Malfunction

Note. If DTC 112 is stored at the same time as DTC 25, troubleshoot DTC 112 first, then recheck for DTC 25.

1. Check for VSA system DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated VSA system DTC(s). NO - Go to step 2.
2. Clear the DTCs with the HDS.
3. Test-drive the vehicle at 28 mph (45 km/h) or more with the adaptive cruise control (ACC) activated, and watch the ACC indicator. Does the ACC indicator come on? YES - Go to step 4. NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.
4. Check for DTCs with the HDS. Is DTC 25 indicated? YES - Go to step 5. NO - Troubleshoot the indicated DTC.
5. Test-drive the vehicle in a straight line with the ACC activated, check YAW RATE S with the HDS. Is about 2.5 V indicated? YES - Go to step 6. NO - Go to VSA system troubleshooting (see «ABS/VSA INDICATOR»(/acura/rl/ii-2004-2008/remont/anti-locktraction-control/#vsa-vehicle-stability-assist-system__absvsa-indicator) ).
6. Turn right with the ACC activated, and check YAW RATE S with the HDS. Does the voltage increase from 2.5 V? YES - Go to step 7. NO - Go to VSA system troubleshooting (see «ABS/VSA INDICATOR»(/acura/rl/ii-2004-2008/remont/anti-locktraction-control/#vsa-vehicle-stability-assist-system__absvsa-indicator) ).
7. Turn left with the ACC activated, and check YAW RATE S with the HDS. Does the voltage decrease from 2.5 V? YES - The yaw rate-lateral/longitudinal acceleration sensor signal is OK, check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Go to VSA system troubleshooting (see «ABS/VSA INDICATOR»(/acura/rl/ii-2004-2008/remont/anti-locktraction-control/#vsa-vehicle-stability-assist-system__absvsa-indicator) ).

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1. Check the brake lights without pressing the brake pedal. Are the brake lights off? YES - Go to step 10 . NO - Go to step 2.
2. Do the brake pedal test and adjustment (see «BRAKE PEDAL AND BRAKE PEDAL POSITION SWITCH ADJUSTMENT»(/acura/rl/ii-2004-2008/remont/mechanical-hydraulic/#conventional-brake-components) ).
3. Check the brake lights without pressing the brake pedal. Are the brake lights off? YES - Intermittent failure, the system is OK at this time. Check for loose or poor connections. NO - Go to step 4.
4. Test the brake pedal position switch (see «HIGH MOUNT BRAKE LIGHT REPLACEMENT»(/acura/rl/ii-2004-2008/remont/exterior-lights/#exterior-lights) ). Is the brake pedal position switch OK? YES - Go to step 5. NO - Adjust or replace the brake pedal position switch and recheck (see «BRAKE PEDAL AND BRAKE PEDAL POSITION SWITCH ADJUSTMENT»(/acura/rl/ii-2004-2008/remont/mechanical-hydraulic/#conventional-brake-components) ).
5. Test the ACC relay (see «POWER RELAY TEST»(/acura/rl/ii-2004-2008/remont/body-electrical/#relays__power-relay-test) ). Is the relay OK? YES - Go to step 6. NO - Replace the relay and recheck.
6. Disconnect the 4P connector from the brake pedal position switch.
7. Measure the voltage between the brake pedal position switch 4P connector No. 2 terminal and body ground. Is there battery voltage? YES - Repair a short to power in the wire. NO - Go to step 8.
8. Disconnect the ACC unit 20P connector.
9. Measure the voltage between the ACC unit 20P connector No. 1 terminal and body ground. Is there battery voltage? YES - Repair a short to power in the wire between the ACC unit and the ACC relay, or between the ACC unit and the brake lights circuits. NO - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ).
10. Clear the DTCs with the HDS.
11. Turn the ACC switch ON.
12. Check the brake lights with the brake pedal pressed. Do the brake lights come on? YES - Go to step 13. NO - Go to step 36 .
13. Check for DTCs with the HDS. Is DTC 30 indicated? YES - Go to step 14 NO - Go to step 20 .
14. Turn the ignition switch OFF.
15. Remove the ACC relay.
16. Disconnect the 20P connector from the ACC unit.
17. Disconnect the brake pedal position switch 4P connector.
18. Check for continuity between the ACC unit 20P connector No. 1 terminal and body ground. Is there continuity? YES - Repair a short to ground in the wire between the ACC unit and the ACC relay. NO - Go to step 19.
19. Check for continuity between the ACC unit 20P connector No. 1 terminal and ACC relay 5P connector No. 1 terminal. Is there continuity? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Repair an open in the wire between the ACC unit and the ACC relay.
20. Test the ACC relay (see «POWER RELAY TEST»(/acura/rl/ii-2004-2008/remont/body-electrical/#relays__power-relay-test) ). Is the relay OK? YES - Go to step 21. NO - Replace the relay and recheck.
21. Remove the ACC relay.
22. Measure the voltage between the ACC relay 5P connector No. 2 terminal and body ground. Is there battery voltage? YES - Go to step 23. NO - Repair an open in the wire between the No. 13 (15 A) fuse in the under-hood fuse/relay box and the ACC relay.
23. Turn the ignition switch ON (II).
24. Measure the voltage between the ACC relay 5P connector No. 5 terminal and body ground. Is there battery voltage? YES - Go to step 25. NO - Repair an open in the wire between the No. 29 (10 A) fuse in the under-dash fuse/relay box and the ACC relay.
25. Turn the ignition switch OFF.
26. Disconnect the 20P connector from the ACC unit.
27. Check for continuity between the ACC unit 20P connector No. 16 terminal and body ground. Is there continuity? YES - Repair a short to ground in the wire between the ACC unit and the ACC relay. NO - Go to step 28.
28. Check for continuity between the ACC unit 20P connector No. 16 terminal and ACC relay 5P connector No. 3 terminal. Is there continuity? YES - Go to step 29. NO - Repair an open in the wire between the ACC unit and the ACC relay.
29. Install the ACC relay.
30. Reconnect the ACC unit 20P connector.
31. Clear the DTCs with the HDS.
32. Turn the ignition switch ON (II) and the ACC switch ON.
33. Select ADAPTIVE CRUISE CONTROL (ACC) from the DRIVING SUPPORT menu, then enter ACC RELAY from the FUNCTION TEST menu.
34. Do the ACC relay function test with the HDS.
35. Check for DTCs with the HDS. Is DTC 30 indicated? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Troubleshoot the indicated DTC. If there is no DTC, the system is OK at this time.
36. Check for the DTCs with the HDS. Is DTC 30 indicated? YES - Go to step 37. NO - Go to step 43 .
37. Do the ACC relay test (see «POWER RELAY TEST»(/acura/rl/ii-2004-2008/remont/body-electrical/#relays__power-relay-test) ). Is the relay OK? YES - Go to step 38. NO - Replace the relay and recheck.
38. Remove the ACC relay.
39. Disconnect the ACC unit 20P connector.
40. Disconnect each brake light 3P connector and the high mount brake light 2P connector.
41. Check for continuity between the ACC unit 20P connector No. 1 terminal and body ground. Is there continuity? YES - Repair a short to ground in the wire between the ACC unit and the ACC relay. NO - Go to step 42.
42. Check for continuity between the ACC unit 20P connector No. 1 terminal and ACC relay 5P connector No. 1 terminal. Is there continuity? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Repair an open in the wire between the ACC unit and the ACC relay.
43. Check the brake lights with the brake pedal pressed. Are the LEDs OK? YES - Intermittent failure, the system is OK at this time. Check for loose or poor connections. NO - Go to step 44.
44. Do the brake pedal test and adjustment (see «BRAKE PEDAL AND BRAKE PEDAL POSITION SWITCH ADJUSTMENT»(/acura/rl/ii-2004-2008/remont/mechanical-hydraulic/#conventional-brake-components) ).
45. Test the brake pedal position switch (see «HIGH MOUNT BRAKE LIGHT REPLACEMENT»(/acura/rl/ii-2004-2008/remont/exterior-lights/#exterior-lights) ).
46. Check the brake lights with the brake pedal pressed. Do the brake lights come on? YES - Intermittent failure, the system is OK at this time. Check for loose or poor connections. NO - Repair an open in the BLK wire or poor ground (G701).

DTC 43: Cal FL Brake System Malfunction

Note. In this troubleshooting, you will operate the ADAPTIVE CRUISE CONTROL (ACC) BRAKE (brake actuator 3) continuously four or five times using the FUNCTION TEST with the HDS. During this operation, the VSA modulator-control unit may stop working. This means the VSA modulator-control unit has shut down to protect the system from overheating during continuous operation.

If the VSA modulator-control unit stops working, wait for a few minutes until the VSA modulator-control unit cools down, then restart the troubleshooting.

1. Check for VSA System DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated VSA system DTC(s). NO - Go to step 2.
2. Start the engine, and turn the ACC switch ON.
3. Clear the DTCs with the HDS.
4. Select ADAPTIVE CRUISE CONTROL (ACC) from the DRIVING SUPPORT menu, then enter the FUNCTION TEST.
5. Activate BRAKE ACTUATOR 3 from the FUNCTION TEST menu.
6. Watch the ACC indicator. Is the ACC indicator amber? YES - Go to step 10 . NO - Go to step 7.
7. Activate BRAKE ACTUATOR 3 again.
8. While the brake actuator is operating, press the brake pedal.
9. Watch the ACC indicator. Does the ACC indicator stay amber? YES - Go to step 10. NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.
10. Check for DTCs with the HDS. Is DTC 43 indicated? YES - Go to step 11. NO - Troubleshoot the indicated DTC(s). If there are no DTCs, the system is OK at this time.
11. Turn the ignition switch OFF.
12. Press the brake pedal several times, and check the brake pedal travel. Is the brake pedal travel OK? YES - Go to step 13. NO - Inspect the master cylinder (see «MASTER CYLINDER INSPECTION»(/acura/rl/ii-2004-2008/remont/mechanical-hydraulic/#conventional-brake-components__master-cylinder-inspection) ).
13. Check for brake fluid leaks (see «BRAKE HOSE AND LINE INSPECTION»(/acura/rl/ii-2004-2008/remont/mechanical-hydraulic/#conventional-brake-components) ). Are there any leaks? YES - Repair the brake fluid leak. NO - Go to step 14.
14. Start the engine.
15. Check the brake switch signal (BRAKE SW (N.O.)) with the HDS. Does the indication show ON with the brake pedal is pressed, and show OFF when the brake pedal is released? YES - Go to step 17 . NO - Go to step 16.
16. Check for DTCs with the HDS. Is DTC 60, 110, or 111 indicated? YES - Troubleshoot the indicated DTC. NO - Troubleshoot the brake pedal position switch circuit (see «BRAKE PEDAL POSITION SWITCH SIGNAL CIRCUIT TROUBLESHOOTING»(/acura/rl/ii-2004-2008/remont/engine-control-systems/#idle-control-system) ).
17. Turn the ACC switch ON.
18. Clear the DTCs with the HDS.
19. Activate the BRAKE ACTUATOR 3 from the FUNCTION TEST.
20. Check for DTCs with the HDS. Is DTC 43 indicated? YES - Check the brake fluid pressure sensor (see «BRAKE FLUID PRESSURE SENSOR REPLACEMENT»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system__brake-fluid-pressure-sensor-replacement) ). If OK, go to step 21. NO - Troubleshoot the indicated DTC. If there is no DTC, the system is OK at this time.
21. Check the left front brake fluid pressure voltage (LF BRAKE P) with the HDS. Is there about 0.5 V? YES - Go to step 22. NO - Go to step 25 .
22. Do the brake booster test (see «BRAKE BOOSTER TEST»(/acura/rl/ii-2004-2008/remont/mechanical-hydraulic/#conventional-brake-components) ).
23. Press the brake pedal with about 314 N (32 kgf, 70.6 lbf) pressure.
24. Check the left front brake fluid pressure voltage (LF BRAKE P) with the HDS. Is there about 2.5 V? YES - The left front brake fluid pressure signal is OK, check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Go to step 25.
25. Check for DTCs with the HDS. Is DTC 43 indicated? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Troubleshoot the indicated DTC. If there is no DTC, the system is OK at this time.

Scheme 30

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Scheme 39

1. Turn the ignition switch ON (II).
2. Clear the DTCs with the HDS.
3. Watch the adaptive cruise control (ACC) indicator. Does the ACC indicator stay off? YES - Intermittent failure, the system is OK at this time. Check for loose or poor connections. NO - Go to step 4.
4. Check for DTCs with the HDS. Is DTC 44 indicated? YES - Go to step 5. NO - Troubleshoot the indicated DTC(s). If there are no DTCs, the system is OK at this time.
5. Check the left front brake fluid pressure voltage (VPRFL) with the HDS. Is there about 0.5 V? YES - Go to step 6. NO - Go to step 9 .
6. Test the brake booster (see «BRAKE BOOSTER TEST»(/acura/rl/ii-2004-2008/remont/mechanical-hydraulic/#conventional-brake-components) ).
7. Press the brake pedal with about 314 N (32 kgf, 70.6 lbf) pressure.
8. Check the left front brake fluid pressure voltage (VPRFL) with the HDS. Is there about 2.5 V? YES - The left front brake fluid pressure signal is OK, check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Go to step 9.
9. Turn the ignition switch OFF.
10. Disconnect the 20P connector from the ACC unit.
11. Check for continuity between the ACC unit 20P connector No. 5 terminal and body ground. Is there continuity? YES - Repair a short to ground in the wire between the ACC unit and the left front pressure sensor. NO - Go to step 12.
12. Disconnect the 3P connector from the left front pressure sensor.
13. Connect the left front pressure sensor 3P connector No. 2 terminal to body ground with a jumper wire.
14. Check for continuity between the ACC unit 20P connector No. 5 terminal and body ground. Is there continuity? YES - Go to step 15. NO - Repair an open in the wire between the ACC unit and the left front pressure sensor.
15. Remove the jumper wire from the left front pressure sensor.
16. Reconnect all connectors.
17. Turn the ignition switch ON (II).
18. Measure the voltage between the ACC unit 20P connector No. 3 and No. 5 terminals. Is there about 5V? YES - Go to step 19. NO - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ).
19. Turn the ignition switch OFF.
20. Disconnect the 20P connector from the ACC unit.
21. Check for continuity between the ACC unit 20P connector No. 14 terminal and body ground. Is there continuity? YES - Repair a short to ground in the wire between the ACC unit and the left front pressure sensor. NO - Go to step 22.
22. Disconnect the 3P connector from the left front pressure sensor.
23. Connect the left front pressure sensor 3P connector No. 3 terminal to body ground with a jumper wire.
24. Check for continuity between the ACC unit 20P connector No. 14 terminal and body ground. Is there continuity? YES - Go to step 25. NO - Repair an open in the wire between the ACC unit and the left front pressure sensor.
25. Check for continuity between the ACC unit 20P connector No. 5 terminal and body ground. Is there continuity? YES - Repair a short in the wire between the PRESS FL line and the VCC line. NO - Go to step 26.
26. Check for continuity between the ACC unit 20P connector No. 3 terminal and body ground. Is there continuity? YES - Go to step 27. NO - Repair an open in the wire between the ACC unit and the left front pressure sensor.
27. Remove the jumper wire from the left front pressure sensor.
28. Reconnect all connectors.
29. Turn the ignition switch ON (II).
30. Measure the voltage between the ACC unit 20P connector No. 3 and No. 14 terminals. Is there about 0.5V? YES - Go to step 31. NO - Replace the left front pressure sensor.
31. Clear the DTCs with the HDS.
32. Watch the ACC indicator. Does the ACC indicator stay off? YES - Intermittent failure, the system is OK at this time. Check for loose or poor connections. NO - Go to step 33.
33. Check for DTCs with the HDS. Is DTC 44 indicated? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Troubleshoot the indicated DTC(s). If there are no DTCs, the system is OK at this time.

Scheme 40

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Scheme 49

1. Turn the ignition switch ON (II).
2. Clear the DTCs with the HDS.
3. Watch the adaptive cruise control (ACC) indicator. Does the ACC indicator stay off? YES - Go to step 4. NO - Go to step 5 .
4. Press the brake pedal, and watch the ACC indicator. Does the ACC indicator stay off? YES - The system is OK at this time. Check for loose or poor connections. NO - Go to step 5.
5. Check for DTCs with the HDS. Is DTC 45 indicated? YES - Go to step 6. NO - Troubleshoot the indicated DTC.
6. Turn the ignition switch OFF.
7. Disconnect the 20P connector from the ACC unit.
8. Check for continuity between the ACC unit 20P connector No. 5 terminal and body ground. Is there continuity? YES - Repair a short to ground in the wire between the ACC unit and the left front pressure sensor. NO - Go to step 9.
9. Disconnect the 3P connector from the left front pressure sensor.
10. Connect the left front pressure sensor 3P connector No. 2 terminal to body ground with a jumper wire.
11. Check for continuity between the ACC unit 20P connector No. 5 terminal and body ground. Is there continuity? YES - Go to step 12. NO - Repair an open in the wire between the ACC unit and the left front pressure sensor.
12. Remove the jumper wire from the left front pressure sensor.
13. Reconnect all connectors.
14. Turn the ignition switch ON (II).
15. Measure the voltage between the ACC unit 20P connector No. 3 and No. 5 terminals. Is there about 5V? YES - Go to step 16. NO - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ).
16. Turn the ignition switch OFF.
17. Disconnect the 20P connector from the ACC unit.
18. Check for continuity between the ACC unit 20P connector No. 14 terminal and body ground. Is there continuity? YES - Repair a short to ground in the wire between the ACC unit and the left front pressure sensor. NO - Go to step 19.
19. Disconnect the 3P connector from the left front pressure sensor.
20. Connect the left front pressure sensor 3P connector No. 3 terminal to body ground with a jumper wire.
21. Check for continuity between the ACC unit 20P connector No. 14 terminal and body ground. Is there continuity? YES - Go to step 22. NO - Repair an open in the wire between the ACC unit and the left front pressure sensor.
22. Check for continuity between the ACC unit 20P connector No. 5 terminal and body ground. Is there continuity? YES - Repair a short in the wire between the PRESS FL line and the VCC line. NO - Go to step 23.
23. Check for continuity between the ACC unit 20P connector No. 3 terminal and body ground. Is there continuity? YES - Go to step 24. NO - Repair an open in the wire between the ACC unit and the left front pressure sensor.
24. Remove the jumper wire from the left front pressure sensor.
25. Reconnect all connectors.
26. Turn the ignition switch ON (II).
27. Check the brake switch signal (BRAKE SW (N.O.)) with the HDS. Does the indication show ON when the brake pedal is pressed, and show OFF when the brake pedal is released? YES - Go to step 29 . NO - Go to step 28.
28. Check for DTCs with the HDS. Is DTC 45 indicated? YES - Go to step 30 . NO - Go to step 29.
29. Check for DTCs with the HDS. Is DTC 60, 110, or 111 indicated? YES - Troubleshoot the indicated DTC. NO - Troubleshoot the brake pedal position switch circuit (see «HIGH MOUNT BRAKE LIGHT REPLACEMENT»(/acura/rl/ii-2004-2008/remont/exterior-lights/#exterior-lights) ).
30. Measure the voltage between the ACC unit 20P connector No. 3 and No. 14 terminals. Is there about 0.5 V? YES - Go to step 31. NO - Replace the left front pressure sensor (see «BRAKE FLUID PRESSURE SENSOR REPLACEMENT»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system__brake-fluid-pressure-sensor-replacement) ).
31. Clear the DTCs with the HDS.
32. Watch the ACC indicator. Does the ACC indicator stay off? YES - The system is OK at this time. Check for loose or poor connections. NO - Go to step 33.
33. Check for DTCs with the HDS. Is DTC 45 indicated? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Troubleshoot the indicated DTC(s). If there are no DTCs, the system is OK at this time.

DTC 46: Cal FL Brake Fluid Pressure Sensor Malfunction

Note. In this troubleshooting, you will operate the ADAPTIVE CRUISE CONTROL (ACC) BRAKE (brake actuator 3) continuously four or five times using the FUNCTION TEST with the HDS. During this operation, the VSA modulator-control unit may stop working. This means the VSA modulator-control unit has shut down to protect the system from overheating during continuous operation.

If the VSA modulator-control unit stops working, wait for a few minutes until the VSA modulator-control unit cools down, then restart the troubleshooting.

Scheme 50

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Scheme 58

1. Start the engine, and turn the ACC switch ON.
2. Clear the DTCs with the HDS.
3. Select ADAPTIVE CRUISE CONTROL (ACC) from the DRIVING SUPPORT menu, then enter the FUNCTION TEST.
4. Activate BRAKE ACTUATOR 3 from the FUNCTION TEST menu.
5. Watch the ACC indicator. Is the ACC indicator amber? YES - Go to step 9 . NO - Go to step 6.
6. Activate BRAKE ACTUATOR 3 again.
7. While the brake actuator is operating, press the brake pedal.
8. Watch the ACC indicator. Does the ACC indicator stay amber? YES - Go to step 9. NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.
9. Check for DTCs with the HDS. Is DTC 46 indicated? YES - Go to step 10. NO - Troubleshoot the indicated DTC(s). If there are no DTCs, the system is OK at this time.
10. Without the brake pedal pressed, check the left front brake fluid pressure voltage (LF BRAKE P) with the HDS. Is there about 0.5 V? YES - Go to step 11. NO - Go to step 14 .
11. Do the brake booster test (see «BRAKE BOOSTER TEST»(/acura/rl/ii-2004-2008/remont/mechanical-hydraulic/#conventional-brake-components) ).
12. Press the brake pedal with about 314 N (32 kgf, 70.6 lbf) pressure.
13. Check the left front brake fluid pressure voltage (LF BRAKE P) with the HDS. Is there about 2.5 V? YES - The left front brake fluid pressure signal is OK, check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Go to step 14.
14. Turn the ignition switch OFF.
15. Disconnect the 20P connector from the ACC unit.
16. Check for continuity between the ACC unit 20P connector No. 5 terminal and body ground. Is there continuity? YES - Repair a short to ground in the wire between the ACC unit and the left front pressure sensor. NO - Go to step 17.
17. Disconnect the 3P connector from the left front pressure sensor.
18. Connect the left front pressure sensor 3P connector No. 2 terminal and body ground with a jumper wire.
19. Check for continuity between the ACC unit 20P connector No. 5 terminal and body ground. Is there continuity? YES - Go to step 20. NO - Repair an open in the wire between the ACC unit and the left front pressure sensor.
20. Remove the jumper wire from the left front pressure sensor.
21. Reconnect all connectors.
22. Turn the ignition switch ON (II).
23. Measure the voltage between the ACC unit 20P connector No. 3 and No. 5 terminals. Is there about 5V? YES - Go to step 24. NO - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ).
24. Turn the ignition switch OFF.
25. Disconnect the 20P connector from the ACC unit.
26. Check for continuity between the ACC unit 20P connector No. 14 terminal and body ground. Is there continuity? YES - Repair a short to ground in the wire between the ACC unit and the left front pressure sensor. NO - Go to step 27.
27. Disconnect the 3P connector from the left front pressure sensor.
28. Connect the left front pressure sensor 3P connector No. 3 terminal to body ground with a jumper wire.
29. Check for continuity between the ACC unit 20P connector No. 14 terminal and body ground. Is there continuity? YES - Go to step 30. NO - Repair an open in the wire between the ACC unit and the left front pressure sensor.
30. Check for continuity between the ACC unit 20P connector No. 5 terminal and body ground. Is there continuity? YES - Repair a short in the wire between the PRESS FL line and the VCC line. NO - Go to step 31.
31. Check for continuity between the ACC unit 20P connector No. 3 terminal and body ground. Is there continuity? YES - Go to step 32. NO - Repair an open in the wire between the ACC unit and the left front pressure sensor.
32. Remove the jumper wire from the left front pressure sensor.
33. Reconnect all connectors.
34. Start the engine.
35. Check the brake switch signal (BRAKE SW (N.O.)) with the HDS. Does the indication show ON when the brake pedal is pressed, and show OFF when the brake pedal is released? YES - Go to step 37 . NO - Go to step 36.
36. Check for DTCs with the HDS. Is DTC 60, 110, or 111 indicated? YES - Troubleshoot the indicated DTC. NO - Troubleshoot the brake pedal position switch circuit (see «HIGH MOUNT BRAKE LIGHT REPLACEMENT»(/acura/rl/ii-2004-2008/remont/exterior-lights/#exterior-lights) ).
37. Turn the ACC switch ON.
38. Clear the DTCs with the HDS.
39. Select ADAPTIVE CRUISE CONTROL (ACC) from the DRIVING SUPPORT menu, then enter the FUNCTION TEST.
40. Activate BRAKE ACTUATOR 3 from the FUNCTION TEST menu.
41. Check for DTCs with the HDS. Is DTC 46 indicated? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Go to the VSA system troubleshooting (see «ABS/VSA INDICATOR»(/acura/rl/ii-2004-2008/remont/anti-locktraction-control/#vsa-vehicle-stability-assist-system__absvsa-indicator) ).

DTC 47: Cal FR Brake System Malfunction

Note. In this troubleshooting, you will operate the ADAPTIVE CRUISE CONTROL (ACC) BRAKE (brake actuator 3) continuously four or five times using the FUNCTION TEST with the HDS. During this operation, the VSA modulator-control unit may stop working. This means the VSA modulator-control unit has shut down to protect the system from overheating during continuous operation.

If the VSA modulator-control unit stops working, wait for a few minutes until the VSA modulator-control unit cools down, then restart the troubleshooting.

1. Check for VSA System DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated VSA system DTC(s). NO - Go to step 2.
2. Start the engine, and turn the ACC switch ON.
3. Clear the DTCs with the HDS.
4. Select ADAPTIVE CRUISE CONTROL (ACC) from the DRIVING SUPPORT menu, then enter the FUNCTION TEST.
5. Activate BRAKE ACTUATOR 3 from the FUNCTION TEST menu.
6. Watch the ACC indicator. Is the ACC indicator amber? YES - Go to step 10 . NO - Go to step 7.
7. Activate BRAKE ACTUATOR 3 again.
8. While the brake actuator is operating, press the brake pedal.
9. Watch the ACC indicator. Does the ACC indicator stay amber? YES - Go to step 10. NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.
10. Check for DTCs with the HDS. Is DTC 47 indicated? YES - Go to step 11. NO - Troubleshoot the indicated DTC(s). If there are no DTCs, the system is OK at this time.
11. Turn the ignition switch OFF.
12. Press the brake pedal several times, and check the brake pedal travel. Is the brake pedal travel OK? YES - Go to step 13. NO - Inspect the master cylinder (see «MASTER CYLINDER INSPECTION»(/acura/rl/ii-2004-2008/remont/mechanical-hydraulic/#conventional-brake-components__master-cylinder-inspection) ).
13. Check for brake fluid leaks (see «BRAKE HOSE AND LINE INSPECTION»(/acura/rl/ii-2004-2008/remont/mechanical-hydraulic/#conventional-brake-components) ). Are there any fluid leaks? YES - Repair the brake fluid leak. NO - Go to step 14.
14. Start the engine.
15. Check the brake switch signal (BRAKE SW (N.O.)) with the HDS. Does the indication show ON when the brake pedal is pressed, and show OFF when the brake pedal is released? YES - Go to step 17 . NO - Go to step 16.
16. Check for DTCs with the HDS. Is DTC 60, 110, or 111 indicated? YES - Troubleshoot the indicated DTC. NO - Troubleshoot the brake pedal position switch circuit (see «BRAKE PEDAL POSITION SWITCH SIGNAL CIRCUIT TROUBLESHOOTING»(/acura/rl/ii-2004-2008/remont/engine-control-systems/#idle-control-system) ).
17. Turn the ACC switch ON.
18. Clear the DTCs with the HDS.
19. Select ADAPTIVE CRUISE CONTROL (ACC) from the DRIVING SUPPORT menu, then enter the FUNCTION TEST.
20. Activate BRAKE ACTUATOR 3 from the FUNCTION TEST.
21. Check for DTCs with the HDS. Is DTC 47 indicated? YES - Check the pressure sensor (see «BRAKE FLUID PRESSURE SENSOR REPLACEMENT»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system__brake-fluid-pressure-sensor-replacement) ). If OK, go to step 22. NO - Troubleshoot the indicated DTC. If there is no DTC, the system is OK at this time.
22. Without the brake pedal pressed, check the right front brake fluid pressure voltage (RF BRAKE P) with the HDS. Is there about 0.5 V? YES - Go to step 23. NO - Go to step 26 .
23. Test the brake booster (see «BRAKE BOOSTER TEST»(/acura/rl/ii-2004-2008/remont/mechanical-hydraulic/#conventional-brake-components) ).
24. Press the brake pedal with about 314 N (32 kgf, 70.6 lbf) pressure.
25. Check the front brake fluid pressure voltage (RF BRAKE P) with the HDS. Is there about 2.5 V? YES - The right front brake fluid pressure signal is OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Go to step 26.
26. Check for DTCs with the HDS. Is DTC 47 indicated? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Troubleshoot the indicated DTC. If there is no DTC, the system is OK at this time.

Scheme 59

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Scheme 68

1. Turn the ignition switch ON (II).
2. Clear the DTCs with the HDS.
3. Watch the adaptive cruise control (ACC) indicator. Does the ACC indicator stay off? YES - Intermittent failure, the system is OK at this time. Check for loose or poor connections. NO - Go to step 4.
4. Check for DTCs with the HDS. Is DTC 48 indicated? YES - Go to step 5. NO - Troubleshoot the indicated DTC(s). If there are no DTCs, the system is OK at this time.
5. Check the right front brake fluid pressure voltage (RF BRAKE P) with the HDS. Is there about 0.5 V? YES - Go to step 6. NO - Go to step 13 .
6. Test the brake booster (see «BRAKE BOOSTER TEST»(/acura/rl/ii-2004-2008/remont/mechanical-hydraulic/#conventional-brake-components) ).
7. Press the brake pedal with about 314 N (32 kgf, 70.6 lbf) pressure.
8. Check the right front brake fluid pressure voltage (RF BRAKE P) with the HDS. Is there about 2.5 V? YES - The right front brake fluid pressure signal is OK, check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Go to step 9.
9. Turn the ignition switch OFF.
10. Disconnect the 20P connector from the ACC unit.
11. Check for continuity between the ACC unit 20P connector No. 5 terminal and body ground. Is there continuity? YES - Repair a short to ground in the wire between the ACC unit and the right front pressure sensor. NO - Go to step 12.
12. Disconnect the 3P connector from the right front pressure sensor.
13. Connect the right front pressure sensor 3P connector No. 2 terminal to body ground with a jumper wire.
14. Check for continuity between the ACC unit 20P connector No. 5 terminal and body ground. Is there continuity? YES - Go to step 15. NO - Repair an open in the wire between the ACC unit and the right front pressure sensor.
15. Remove the jumper wire from the right front pressure sensor.
16. Reconnect all connectors.
17. Turn the ignition switch ON (II).
18. Measure the voltage between the ACC unit 20P connector No. 3 and No. 5 terminals. Is there about 5V? YES - Go to step 19. NO - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ).
19. Turn the ignition switch OFF.
20. Disconnect the 20P connector from the ACC unit.
21. Check for continuity between the ACC unit 20P connector No. 6 terminal and body ground. Is there continuity? YES - Repair a short to ground in the wire between the ACC unit and the right front pressure sensor. NO - Go to step 22.
22. Disconnect the 3P connector from the right front pressure sensor.
23. Connect the right front pressure sensor 3P connector No. 3 terminal to body ground with a jumper wire.
24. Check for continuity between the ACC unit 20P connector No. 6 terminal and body ground. Is there continuity? YES - Go to step 25. NO - Repair an open in the wire between the ACC unit and the right front pressure sensor.
25. Check for continuity between the ACC unit 20P connector No. 5 terminal and body ground. Is there continuity? YES - Repair a short in the wire between the PRESS FR line and VCC line. NO - Go to step 26.
26. Check for continuity between the ACC unit 20P connector No. 3 terminal and body ground. Is there continuity? YES - Go to step 27. NO - Repair an open in the wire between the ACC unit and the right front pressure sensor.
27. Remove the jumper wire from the right front pressure sensor.
28. Reconnect all connectors.
29. Turn the ignition switch ON (II).
30. Measure the voltage between the ACC unit 20P connector No. 3 and No. 6 terminals. Is there about 0.5V? YES - Go to step 31. NO - Replace the right front pressure sensor.
31. Clear the DTCs with the HDS.
32. Watch the ACC indicator. Does the ACC indicator stay off? YES - Intermittent failure, the system is OK at this time. Check for loose or poor connections. NO - Go to step 33.
33. Check for DTCs with the HDS. Is DTC 48 indicated? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Troubleshoot the indicated DTC(s). If there are no DTCs, the system is OK at this time.

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1. Turn the ignition switch ON (II).
2. Clear the DTCs with the HDS.
3. Watch the adaptive cruise control (ACC) indicator. Does the ACC indicator stay off? YES - Go to step 4. NO - Go to step 5 .
4. Press the brake pedal, and watch the ACC indicator. Does the ACC unit indicator stay off? YES - The system is OK at this time. Check for loose or poor connections. NO - Go to step 5.
5. Check for DTCs with the HDS. Is DTC 49 indicated? YES - Go to step 6. NO - Troubleshoot the indicated DTC(s). If there are no DTCs, the system is OK at this time.
6. Turn the ignition switch OFF.
7. Disconnect the 20P connector from the ACC unit.
8. Check for continuity between the ACC unit 20P connector No. 5 terminal and body ground. Is there continuity? YES - Repair a short to ground in the wire between the ACC unit and the right front pressure sensor. NO - Go to step 9.
9. Disconnect the 3P connector from the right front pressure sensor.
10. Connect the right front pressure sensor 3P connector No. 2 terminal to body ground with a jumper wire.
11. Check for continuity between ACC unit 20P connector No. 5 terminal and body ground. Is there about 5V? YES - Go to step 12. NO - Repair a short to ground in the wire between the ACC unit and the right front pressure sensor.
12. Remove the jumper wire from the right front pressure sensor.
13. Reconnect all connectors.
14. Turn the ignition switch ON (II).
15. Measure the voltage between the ACC unit 20P connector No. 3 and No. 5 terminals. Is there about 5V? YES - Go to step 16. NO - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ).
16. Turn the ignition switch OFF.
17. Disconnect the 20P connector from the ACC unit
18. Check for continuity between the ACC unit 20P connector No. 6 terminal and body ground. Is there continuity? YES - Repair a short to ground in the wire between the ACC unit and the right front pressure sensor. NO - Go to step 19.
19. Disconnect the 3P connector from the right front pressure sensor.
20. Connect the right front pressure sensor 3P connector No. 3 terminal to body ground with a jumper wire.
21. Check for continuity between the ACC unit 20P connector No. 6 terminal and body ground. Is there continuity? YES - Go to step 22. NO - Repair an open in the wire between the ACC unit and the right front pressure sensor.
22. Check for continuity between the ACC unit 20P connector No. 5 terminal and body ground. Is there continuity? YES - Repair a short in the wire between the PRESS FR line and VCC line. NO - Go to step 23.
23. Check for continuity between the ACC unit 20P connector No. 3 terminal and body ground. Is there continuity? YES - Go to step 24. NO - Repair an open in the wire between the ACC unit and the right front pressure sensor.
24. Remove the jumper wire from the right front pressure sensor.
25. Reconnect all connectors.
26. Turn the ignition switch ON (II).
27. Check the brake switch signal (BRAKE SW (N. O.)) with the HDS. Does the indication show ON when the brake pedal is pressed, and show OFF when the brake pedal is released? YES - Go to step 29 . NO - Go to step 28.
28. Check for DTCs with the HDS. Is DTC 49 indicated? YES - Go to step 30 . NO - Go to step 29.
29. Check for DTCs with the HDS. Is DTC 60, 110, or 111 indicated? YES - Troubleshoot the indicated DTC. NO - Troubleshoot the brake pedal position switch circuit (see «HIGH MOUNT BRAKE LIGHT REPLACEMENT»(/acura/rl/ii-2004-2008/remont/exterior-lights/#exterior-lights) ).
30. Measure the voltage between the ACC unit 20P connector No. 3 and No. 6 terminals. Is there about 0.5V? YES - Go to step 31. NO - Replace the right front pressure sensor (see «BRAKE FLUID PRESSURE SENSOR REPLACEMENT»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system__brake-fluid-pressure-sensor-replacement) ).
31. Clear the DTCs with the HDS.
32. Watch the ACC unit indicator. Does the ACC unit indicator stay off? YES - The system is OK at this time. Check for loose or poor connections. NO - Go to step 33.
33. Check for DTCs with the HDS. Is DTC 49 indicated? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Troubleshoot the indicated DTC(s). If there are no DTCs, the system is OK at this time.

DTC 50: Cal FR Brake Fluid Pressure Sensor Malfunction

Note. In this troubleshooting, you will operate the ADAPTIVE CRUISE CONTROL (ACC) BRAKE (brake actuator 3) continuously four or five times using the FUNCTION TEST with the HDS. During this operation, the VSA modulator-control unit may stop working. This means the VSA modulator-control unit has shut down to protect the system from overheating during continuous operation.

If the VSA modulator-control unit stops working, wait for a few minutes until the VSA modulator-control unit cools down, then restart the troubleshooting.

Scheme 79

Scheme 80

Scheme 81

Scheme 82

Scheme 83

Scheme 84

Scheme 85

Scheme 86

Scheme 87

1. Start the engine, and turn the ACC switch ON.
2. Clear the DTCs with the HDS.
3. Select ADAPTIVE CRUISE CONTROL (ACC) from the DRIVING SUPPORT menu, then enter the FUNCTION TEST.
4. Activate BRAKE ACTUATOR 3 from the FUNCTION TEST menu.
5. Watch the ACC indicator. Is the ACC indicator amber? YES - Go to step 9 . NO - Go to step 6.
6. Activate BRAKE ACTUATOR 3 again.
7. While the brake actuator is operating, press the brake pedal.
8. Watch the ACC indicator. Does the ACC indicator stay amber? YES - Go to step 9. NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.
9. Check for DTCs with the HDS. Is DTC 50 indicated? YES - Go to step 10. NO - Troubleshoot the indicated DTC(s). If there are no DTCs, the system is OK at this time.
10. Without the brake pedal pressed, check the right front brake fluid pressure voltage (RF BRAKE P) with the HDS. Is there about 0.5 V? YES - Go to step 11. NO - Go to step 14 .
11. Test the brake booster (see «BRAKE BOOSTER TEST»(/acura/rl/ii-2004-2008/remont/mechanical-hydraulic/#conventional-brake-components) ).
12. Press the brake pedal with about 314 N (32 kgf, 70.6 lbf) pressure.
13. Check the right front brake fluid pressure voltage (RF BRAKE P) with the HDS. Is there about 2.5 V? YES - The right front brake fluid pressure signal is OK, check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Go to step 14.
14. Turn the ignition switch OFF.
15. Disconnect the 20P connector from the ACC unit.
16. Check for continuity between the ACC unit 20P connector No. 5 terminal and body ground. Is there continuity? YES - Repair a short to ground in the wire between the ACC unit and the right front pressure sensor. NO - Go to step 17.
17. Disconnect the 3P connector from the right front pressure sensor.
18. Connect the right front pressure sensor 3P connector No. 2 terminal to body ground with a jumper wire.
19. Check for continuity between the ACC unit 20P connector No. 5 terminal and body ground. Is there continuity? YES - Go to step 20. NO - Repair an open in the wire between the ACC unit and the right front pressure sensor.
20. Remove the jumper wire from the right front pressure sensor.
21. Reconnect all connectors.
22. Turn the ignition switch ON (II).
23. Measure the voltage between the ACC unit 20P connector No. 3 and No. 5 terminals. Is there about 5V? YES - Go to step 24. NO - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ).
24. Turn the ignition switch OFF.
25. Disconnect the 20P connector from the ACC unit.
26. Check for continuity between the ACC unit 20P connector No. 6 terminal and body ground. Is there continuity? YES - Repair a short to ground in the wire between the ACC unit and the right front pressure sensor. NO - Go to step 27.
27. Disconnect the 3P connector from the right front pressure sensor.
28. Connect the right front pressure sensor 3P connector No. 3 terminal to body ground with a jumper wire.
29. Check for continuity between the ACC unit 20P connector No. 6 terminal and body ground. Is there continuity? YES - Go to step 30. NO - Repair an open in the wire between the ACC unit and the right front pressure sensor.
30. Check for continuity between the ACC unit 20P connector No. 5 terminal and body ground. Is there continuity? YES - Repair a short in the wire between the PRESS FR line and the VCC line. NO - Go to step 31.
31. Check for continuity between the ACC unit 20P connector No. 3 terminal and body ground. Is there continuity? YES - Go to step 32. NO - Repair an open in the wire between the ACC unit and the right front pressure sensor.
32. Remove the jumper wire from the right front pressure sensor.
33. Reconnect all connectors.
34. Start the engine.
35. Check the brake switch signal (BRAKE SW (N.O..)) with the HDS. Does the indication show ON when the brake pedal is pressed, and show OFF when the brake pedal is released? YES - Go to step 37 . NO - Go to step 36.
36. Check for DTCs with the HDS. Is DTC 60, 110, or 111 indicated? YES - Troubleshoot the indicated DTC. NO - Troubleshoot the brake pedal position switch circuit (see «HIGH MOUNT BRAKE LIGHT REPLACEMENT»(/acura/rl/ii-2004-2008/remont/exterior-lights/#exterior-lights) ).
37. Turn the ACC switch ON.
38. Clear the DTCs with the HDS.
39. Select ADAPTIVE CRUISE CONTROL (ACC) from the DRIVING SUPPORT menu, then enter the FUNCTION TEST.
40. Activate BRAKE ACTUATOR 3 from the FUNCTION TEST menu.
41. Check for DTCs with the HDS. Is DTC 50 indicated? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Go to the VSA system troubleshooting (see «ABS/VSA INDICATOR»(/acura/rl/ii-2004-2008/remont/anti-locktraction-control/#vsa-vehicle-stability-assist-system__absvsa-indicator) ).

Scheme 88

1. Clear the DTCs with the HDS.
2. Turn the ignition switch ON (II).
3. Turn the adaptive cruise control (ACC) switch ON.
4. Watch the ACC indicator. Does the ACC indicator stay off? YES - Intermittent failure, the system is OK at this time. Check for loose or poor connections. NO - Go to step 5.
5. Check for DTCs with the HDS. Is DTC 60 indicated? YES - Go to step 6. NO - Troubleshoot the indicated DTC(s). If there are no DTCs, the system is OK at this time.
6. Turn the ignition switch OFF.
7. Disconnect the 20P connector from the ACC unit.
8. Check resistance between the ACC unit 20P connector No. 10 and No. 20 terminals. Is there about 60 0, at room temperature? YES - The F-CAN line is OK at this time, check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Repair an open in the wire between the ACC unit and the branch of the communication line (CANL line or CANH line.)

Scheme 89

Scheme 90

Scheme 91

Scheme 92

Scheme 93

1. Clear the DTC with the HDS.
2. Turn the ignition switch ON (II).
3. Watch the adaptive cruise control (ACC) indicator and CMBS indicator. Do both indicators come on? YES - Go to step 4. NO - Intermittent failure, the system is OK at this time.
4. Check for DTCs with the HDS. Is DTC 61 indicated? YES - Go to step 5. NO - Troubleshoot the indicated DTC(s). If there are no DTCs, the system is OK at this time.
5. Turn the ignition switch OFF.
6. Check the No. 29 (7.5 A) fuse in the under-dash fuse/relay box. Is the fuse OK? YES - Go to step 7. NO - Replace the fuse and recheck.
7. Disconnect the 5P connector from the millimeter wave radar unit.
8. Turn the ignition switch ON (II).
9. Measure the voltage between the millimeter wave, radar unit 5P connector No. 1 terminal and body ground. Is there battery voltage? YES - Go to step 10. NO - Repair an open in the wire between the millimeter wave radar unit and the No: 29 (7.5 A) fuse in the under-dash fuse/relay box.
10. Turn the ignition switch OFF.
11. Check for continuity between the millimeter wave radar unit 5P connector No. 4 terminal and body ground. Is there continuity? YES - Go to step 12. NO - Repair an open in the wire or poor ground (G401).
12. Turn the ignition switch ON (II) and ACC switch ON.
13. Measure the voltage between the millimeter wave radar unit 5P connector No. 5 terminal and body ground. Is there battery voltage? YES - Go to step 15 . NO - Go to step 14.
14. Measure the voltage between the ACC unit 20P connector No. 17 terminal and body ground. Is there battery voltage? YES - Repair an open in the wire between the ACC unit and the millimeter wave radar unit. NO - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ), then go to step 18 .
15. Turn the ignition switch OFF.
16. Disconnect the 20P connector from the ACC unit.
17. Check for continuity between the millimeter wave radar unit 5P connector No. 5 terminal and body ground. Is there continuity? YES - Repair a short to ground in the wire between the ACC unit and the millimeter wave radar unit. NO - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ), then go to step 18.
18. Clear the DTCs with the HDS.
19. Turn the ignition switch ON (II).
20. Watch the ACC indicator and CMBS indicator. Do both indicators come on? YES - Go to step 21. NO - Intermittent failure, the system is OK at this time.
21. Check for DTCs with the HDS. Is DTC 61 indicated? YES - Check for loose or poor connections. If OK, Replace the millimeter wave radar unit (see «MILLIMETER WAVE RADAR UNIT REMOVAL/INSTALLATION»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). After replacement, aim the millimeter wave radar unit (see «MILLIMETER WAVE RADAR UNIT AIMING»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system__millimeter-wave-radar-unit-aiming) ). NO - Troubleshoot the indicated DTC(s). If there are no DTCs, the system is OK at this time.

DTC 62: Millimeter Wave Radar Sensor Error

1. Clear the DTCs with the HDS.
2. Turn the ignition switch ON (II) and the adaptive cruise control (ACC) switch ON.
3. Check for DTCs with the HDS. Is DTC 62 indicated? YES - Check for loose or poor connections. If OK, replace the millimeter wave radar unit (see «MILLIMETER WAVE RADAR UNIT REMOVAL/INSTALLATION»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). After replacement, aim the millimeter wave radar unit (see «MILLIMETER WAVE RADAR UNIT AIMING»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system__millimeter-wave-radar-unit-aiming) ). NO - Intermittent failure, the system is OK at this time.

DTC 63: Millimeter Wave Radar Unit Aiming Error

1. Watch the adaptive cruise control (ACC) indicator and CMBS indicator. Do both indicators come on? YES - Go to step 2. NO - Intermittent failure, the system is OK at this time.
2. Check for DTCs with the HDS. Is DTC 63 indicated? YES - Go to step 3. NO - Troubleshoot the indicated DTC(s). If there are no DTCs, the system is OK at this time.
3. Remove the upper grille (see «UPPER GRILLE REPLACEMENT»(/acura/rl/ii-2004-2008/remont/exteriorinterior-trim/#exterior-trim__upper-grille-replacement) ).
4. Check the installation of the millimeter wave radar unit and the main bracket. Is the installation OK? YES - Go to step 5. NO - Reinstall or replace the part that has a problem, then go to step 5.
5. Aim the millimeter wave radar unit procedure (see «MILLIMETER WAVE RADAR UNIT AIMING»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system__millimeter-wave-radar-unit-aiming) ).
6. Test-drive the vehicle at 25 mph (40 km/h) or more, and turn the ACC switch ON.
7. With the ACC activated, test-drive the vehicle on a straight road at 25 mph (40 km/h) or more for 5 minutes or more.
8. Watch the ACC indicator and CMBS indicator. Do both indicators come on? YES - Go to step 9. NO - The system is OK at this time.
9. Check for DTCs with the HDS. Is DTC 63 indicated? YES - Check for loose or poor connections. If OK, replace the millimeter wave radar unit (see «MILLIMETER WAVE RADAR UNIT REMOVAL/INSTALLATION»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). After replacement, aim the millimeter wave radar unit (see «MILLIMETER WAVE RADAR UNIT AIMING»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system__millimeter-wave-radar-unit-aiming) ). NO - Troubleshoot the indicated DTC(s). If there are no DTCs, the system is OK at this time.

DTC 81: Engine control System (Including PCM) Malfunction

1. Check for PGM-FI System DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated PGM-FI system DTC(s). NO - Go to step 2.
2. Clear the DTCs with the HDS.
3. Test-drive the vehicle with the adaptive cruise control (ACC) activated.
4. Check for DTCs with the HDS. Is DTC 81 indicated? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.

DTC 90: A/T Control System (Including PCM) Malfunction

1. Check for A/T System DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated A/T system DTC(s). NO - Go to step 2.
2. Clear the DTCs with the HDS.
3. Test-drive the vehicle with the adaptive cruise control (ACC) activated.
4. Check for DTCs with the HDS. Is DTC 90 indicated? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.

DTC 92: VSA Modulator-Control Unit Malfunction

1. Check for VSA System DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated VSA system DTC(s). NO - Go to step 2.
2. Clear the DTCs with the HDS.
3. Test-drive the vehicle with the adaptive cruise control (ACC) activated.
4. Check for DTCs with the HDS. Is DTC 92 indicated? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.

DTC 105: Dust or Dirt on the Millimeter Wave Radar Unit

Note. When driving on a road with little traffic and minimal reflecting objects for the millimeter wave radar, DTC 105 is stored temporally. Also DTC 105 is sometimes stored near overpasses, and bodies of water. Check for dirt on the front surface of the millimeter wave radar unit.

1. Check for dust or dirt on the millimeter wave radar unit. Is the surface dirty? YES - Clean the millimeter wave radar unit, then recheck the system. NO - Go to step 2.
2. Remove the upper grille (see «UPPER GRILLE REPLACEMENT»(/acura/rl/ii-2004-2008/remont/exteriorinterior-trim/#exterior-trim__upper-grille-replacement) ).
3. Check the installation of the emblem. Is the emblem installed correctly? YES - Intermittent failure, the system is OK at this time. NO - Reinstall the emblem or the upper grille correctly. If damaged, replace it.

DTC 107: Millimeter Wave Radar Unit Aiming Incomplete

Note. If the millimeter wave radar unit is removed or replaced, it is necessary to aim it, otherwise DTC 107 is stored even if the system is OK.

1. Turn the ignition switch ON (II), and watch the adaptive cruise control (ACC) indicator. Does the ACC indicator stay off? YES - Intermittent failure, the system is OK at this time. NO - Go to step 2.
2. Check for DTCs with the HDS. Is DTC 107 indicated? YES - If DTC 107 is indicated again after the aiming is complete, check for loose or poor connections. If OK, replace the millimeter wave radar unit (see «MILLIMETER WAVE RADAR UNIT REMOVAL/INSTALLATION»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Go to step 3.
3. Check for DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated DTC. NO - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ), then go to step 4.
4. Check for DTCs with the HDS. Is DTC 107 indicated? YES - Check for loose or poor connections. If OK, replace the millimeter wave radar unit (see «MILLIMETER WAVE RADAR UNIT REMOVAL/INSTALLATION»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Troubleshoot the indicated DTC. If there is no DTC, the system is OK at this time.

Scheme 94

Scheme 95

1. Check for PGM-FI system DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated PGM-FI system DTC(s). NO - Go to step 2.
2. Check the DTCs with the HDS.
3. Turn the ignition switch ON (II) and adaptive cruise control (ACC) switch ON.
4. Check for DTCs with the HDS. Is DTC 110 or 111 indicated? YES - Go to step 5. NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.
5. Turn the ignition switch OFF.
6. Disconnect the 20P connector from the ACC unit.
7. Jump the SCS line with the HDS, then disconnect PCM connector A (31P) (see «SUBSTITUTING THE PCM»(/acura/rl/ii-2004-2008/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-pcm) ).
8. Check for continuity between the ACC unit 20P connector No. 10 terminal and PCM connector A (31P) No. 15 terminal. Is there continuity? YES - Go to step 9. NO - Repair an open in the wire between the ACC unit and the branch of the F-CAN line (CANH).
9. Check for continuity between the ACC unit 20P connector No. 20 terminal and PCM connector A (31P) No. 26 terminal. Is there continuity? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Repair an open in the wire between the ACC unit and the branch of the F-CAN line (CANL).

Scheme 96

Scheme 97

1. Check for VSA system DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated VSA system DTC(s). NO - Go to step 2.
2. Clear the DTCs with the HDS.
3. Turn the adaptive cruise control (ACC) switch ON.
4. Check for DTCs with the HDS. Is DTC 112 indicated? YES - Go to step 5. NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.
5. Turn the ignition switch OFF.
6. Disconnect the 20P connector from the ACC unit.
7. Disconnect the VSA modulator-control unit 47P connector.
8. Check for continuity between the ACC unit 20P connector No. 10 terminal and the VSA modulator-control unit 47P connector No. 14 terminal. Is there continuity? YES - Go to step 9. NO - Repair an open in the wire between the ACC unit and the branch of the F-CAN line (CANH).
9. Check for continuity between the ACC unit 20P connector No. 20 terminal and the VSA modulator-control unit 47P connector No. 30 terminal. Is there continuity? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Repair an open in the wire between the ACC unit and the branch of the F-CAN line (CANL).

Scheme 98

Scheme 99

1. Check the gauge control module with the gauge control module self-diagnostic function. Is the gauge control module OK? YES - Go to step 2. NO - Replace the gauge control module and recheck.
2. Clear the DTCs with the HDS.
3. Turn the ignition switch ON (II) and the adaptive cruise control (ACC) switch ON.
4. Check for DTCs with the HDS. Is DTC 113 indicated? YES - Go to step 5. NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.
5. Turn the ignition switch OFF.
6. Disconnect the 20P connector from the ACC unit.
7. Disconnect gauge control module connector B (28P).
8. Check for continuity between the ACC unit 20P connector No. 10 terminal and gauge control module connector B (28P) No. 16 terminal. Is there continuity? YES - Go to step 9. NO - Repair an open in the wire between the ACC unit and the branch of the F-CAN line (CANH).
9. Check for continuity between the ACC unit 20P connector No. 20 terminal and gauge control module connector B (28P) No. 15 terminal. Is there continuity? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Repair an open in the wire between the ACC unit and the branch of the F-CAN line (CANL).

Scheme 100

Scheme 101

1. Check for SH-AWD system DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated SH-AWD system DTC(s). NO - Go to step 2.
2. Clear the DTCs with the HDS.
3. Turn the ignition switch ON (II) and the adaptive cruise control (ACC) switch ON.
4. Check for DTCs with the HDS. Is DTC 115 indicated? YES - Go to step 5. NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.
5. Turn the ignition switch OFF.
6. Disconnect the 20P connector from the ACC unit.
7. Disconnect the SH-AWD control unit 26P connector.
8. Check for continuity between the ACC unit 20P connector No. 10 terminal and the SH-AWD control unit 26P connector No. 11 terminal. Is there continuity? YES - Go to step 9. NO - Repair an open in the wire between the ACC unit and the branch of the F-CAN line (CANH).
9. Check for continuity between the ACC unit 20P connector No. 20 terminal and the SH-AWD control unit 26P connector No. 10 terminal. Is there continuity? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Repair an open in the wire between the ACC unit and the branch of the F-CAN line (CANL).

Scheme 102

Scheme 103

1. Check the No. 29 (7.5 A) fuse in the under-dash fuse/relay box. Is the fuse OK? YES - Go to step 2. NO - Check for a short in the wire between the No. 29 (7.5 A) fuse socket and the ACC unit. If OK, replace the fuse.
2. Disconnect the 20P connector from the ACC unit.
3. Turn the ignition switch ON (II).
4. Measure the voltage between the ACC unit 20P connector No. 2 terminal and body ground. Is there battery voltage? YES - Go to step 5. NO - Repair an open in the wire between the No. 29 (7.5 A) fuse in the under-dash fuse/relay box and the ACC unit. If the wire is OK, replace the under-dash fuse/relay box.
5. Turn the ignition switch OFF.
6. Check for continuity between the ACC unit 20P connector No. 11 and No. 12 terminals and body ground individually. Is there continuity? YES - The system is OK at this time. Go to the appropriate step according to these symptoms: If the ACC system detects a vehicle driving in another lane, go to step 7. If the ACC system does not detect the vehicle driving ahead, go to step 11 . If the ACC system does not detect the vehicle driving ahead consistently, go to step 22 . NO - Repair an open in the wire or poor ground (G401).
7. Check the vehicle's history for front end collision repairs. Has the vehicle been repaired? YES - Go to step 8. NO - Go to step 9 .
8. Check if the millimeter wave radar unit and the main bracket are installed correctly, and also check if the vehicle frame is straight. Are all parts installed correctly? YES - Aim the millimeter wave radar unit (see «MILLIMETER WAVE RADAR UNIT AIMING»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system__millimeter-wave-radar-unit-aiming) ). NO - Reinstall the part correctly, or if damaged, replace the part, then aim the millimeter wave radar unit (see «MILLIMETER WAVE RADAR UNIT AIMING»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system__millimeter-wave-radar-unit-aiming) ).
9. Check the wheel alignment. Is the wheel alignment OK? YES - Go to step 10. NO - Adjust the wheel alignment (see «WHEEL ALIGNMENT»(/acura/rl/ii-2004-2008/remont/wheel-alignment/#front-suspension-and-rear-suspension-alignment__wheel-alignment) ).
10. Find out when the system has misdetections. Do they occur within 20 minutes or less? YES - Go to step 11. NO - Explain to the client that system misdetections are sometimes caused by the environment (weather, road conditions, driving conditions, etc.).
11. Find out if the misdetection occurs only with certain types of vehicles. Does it occur only with certain types of vehicles such as a truck, motorcycle, or special vehicle? YES - Explain to the client that system misdetections are sometimes caused by the vehicle types. NO - Go to step 12.
12. Check for dirt, dust, or snow on the surface of the millimeter wave radar unit and the emblem. Are the radar and emblem OK? YES - Go to step 13. NO - Clean the radar and the emblem. There is no DTC for dirty conditions.
13. Check if there was a heavy load in the trunk. Was there a heavy load in the trunk? YES - Remove the heavy load from the trunk. Advice the customer that this problem may occur temporarily when hauling loads. NO - Go to step 14.
14. Measure the front and rear vehicle ride height. Is the vehicle ride height equal? YES - Go to step 15. NO - Adjust the wheel alignment (see «WHEEL ALIGNMENT»(/acura/rl/ii-2004-2008/remont/wheel-alignment/#front-suspension-and-rear-suspension-alignment__wheel-alignment) ).
15. Find out if the detection problem occurs only with certain types of vehicles (dirty vehicle, tall vehicle, motorcycle, or special vehicle). Does it occur only with certain types of vehicles? YES - Explain to the client that the system sometimes cannot detect certain vehicle types. NO - Go to step 16.
16. Find out if the detection problem occurs only on a particular road such as a winding road, an entrance of a corner, exit of a corner, a tight corner, or a bad road. Does it occur only on a particular road? YES - Explain to the client that the system sometimes cannot detect under certain road conditions. NO - Go to step 17.
17. Find out if the detection problem occurs only under poor weather conditions such as a fog, snow, heavy rain, or gusty winds. Does it occur only under poor weather conditions? YES - Explain to the client that the system sometimes cannot detect under poor weather conditions. NO - Go to step 18.
18. Find out if the detection problem occurs only when the vehicle ahead drives under these conditions: driving in a zigzag line. merged into the lane suddenly. closing on a vehicle within 13 ft (4 m). Does it occur only under certain driving conditions? YES - Explain to the client that the system sometimes cannot detect under certain driving conditions. NO - Go to step 19.
19. Find out if the detection problem occurs under all conditions. Does it occur under all conditions? YES - The millimeter wave radar unit vertical aiming is incorrect. Readjust the aiming. NO - Go to step 20.
20. Confirm if the radar detects vehicles driving in another lane. Does it detect vehicles in other lanes? YES - The millimeter wave radar unit horizontal aiming is incorrect. Readjust the aiming. NO - Go to step 21.
21. Confirm if the detection problem is caused by instability. NOTE: If the cause of the misdetection or undetectable problems is unclear, it is possible that the problem was caused by environmental conditions. Explain to the client that intermittent failures are sometimes caused by environmental conditions. Is the vehicle unstable? (Compare it to a known-good, like vehicle.) YES - Check the other components such as the yaw rate sensor or wheel sensors, etc. NO - The system is OK at this time.
22. Check for dirt, dust, or snow on the surface of the millimeter wave radar unit and the emblem. Are the radar unit and the emblem OK? YES - Go to step 23. NO - Clean the radar unit and the emblem. There is no DTC for dirty conditions.
23. Check the vehicle's history for front end collision repairs. Has the vehicle been repaired? YES - Go to step 24. NO - Go to step 25 .
24. Check if the millimeter wave radar unit and the main bracket are installed correctly, and also check if the vehicle frame is straight. Are all parts installed correctly? YES - Aim the millimeter wave radar unit (see «MILLIMETER WAVE RADAR UNIT AIMING»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system__millimeter-wave-radar-unit-aiming) ). NO - Reinstall the part correctly, or if damaged, replace the part, then aim the millimeter wave radar unit (see «MILLIMETER WAVE RADAR UNIT AIMING»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system__millimeter-wave-radar-unit-aiming) ).
25. Check if there was a heavy load in the trunk. Was there a heavy load in the trunk? YES - Remove the heavy load from the trunk. Advice the client that this problem may occur temporarily when hauling loads. NO - Go to step 26.
26. Measure the front and rear vehicle ride height. Is the vehicle ride height equal? YES - Go to step 27. NO - Adjust the wheel alignment (see «WHEEL ALIGNMENT»(/acura/rl/ii-2004-2008/remont/wheel-alignment/#front-suspension-and-rear-suspension-alignment__wheel-alignment) ).
27. Find out if the detection problem occurs only with certain types of vehicles (dirty vehicle, tall vehicle, motorcycle, or special vehicle). Does it occur only with certain types of vehicles? YES - Explain to the client that the system sometimes cannot detect certain vehicle types. NO - Go to step 28.
28. Find out if the detection problem occurs only on a particular road such as a winding road, an entrance of a corner, exit of a corner, a tight corner, or a bad road. Does it occur only on a particular road? YES - Explain to the client that the system sometimes cannot detect under certain road conditions. NO - Go to step 29.
29. Find out if the detection problem occurs only under poor weather conditions such as a fog, snow, heavy rain, or gusty winds. Does it occur only under poor weather conditions? YES - Explain to the client that the system sometimes cannot detect under poor weather conditions. NO - Go to step 30.
30. Find out if the detection problem occurs only when the vehicle ahead drives under these conditions: driving in a zigzag line. merged into the lane suddenly. closing on a vehicle within 13 ft (4 m). Does it occur only under certain driving conditions? YES - Explain to the client that the system sometimes cannot detect under certain driving conditions. NO - Go to step 31.
31. Find out if the detection problem occurs under all conditions. Does it occur under all conditions? YES - The millimeter wave radar unit vertical aiming is incorrect. Readjust the aiming. NO - Go to step 32.
32. Confirm if the radar detects vehicles driving in another lane. Does it detect vehicles in other lanes? YES - The millimeter wave radar unit horizontal aiming is incorrect. Readjust the aiming. NO - Go to step 33.
33. Confirm if the detection problem is caused by vehicle instability. NOTE: If the cause of the misdetection or undetectable problems is unclear, it is possible that the problem was caused by many environmental conditions. Explain to the customer that intermittent failures are sometimes caused by environmental conditions. Is the vehicle unstable? YES - Check the other components such as the yaw rate sensor or wheel sensors, etc. NO - The system is OK at this time.

Scheme 104

1. Turn the ignition switch ON (II).
2. Watch the following indicators in the gauge control module: MIL Brake system light Charging light Do the indicators come on? YES - Go to the gauge control module self-diagnostic function (see «SELF-DIAGNOSTIC FUNCTION»(/acura/rl/ii-2004-2008/remont/gauges-instrument-panels/#gauges__self-diagnostic-function) ). NO - Go to step 3.
3. Turn the ignition switch OFF.
4. Check the No. 21 (10 A) fuse in the under-dash fuse/relay box. Is the fuse OK? YES - Go to step 5. NO - Replace the fuse, then recheck.
5. Disconnect gauge control module connector B (28P).
6. Turn the ignition switch ON (II).
7. Measure the voltage between the gauge control module connector B (28P) No. 1 terminal and body ground. Is there battery voltage? YES - Substitute a known-good gauge control module and recheck. If the problem goes away, replace the original gauge control module (see «GAUGE CONTROL MODULE REPLACEMENT»(/acura/rl/ii-2004-2008/remont/gauges-instrument-panels/#gauges__gauge-control-module-replacement) ). NO - Repair an open in the wire, if the wire is OK, replace the under-dash fuse/relay box.

Adaptive cruise control (ACC) indicator (amber) does not go off

1. Turn the ignition switch OFF.
2. Connect the HDS to the data link connector.
3. Check for DTCs with the HDS. Is any DTC indicated? YES - Troubleshoot the indicated DTC. NO - Go to step 4.
4. Start the engine, and wait for 2 seconds.
5. Watch the ACC indicator. Does the ACC indicator go off? YES - Intermittent failure, the system is OK at this time. Check for loose or poor connections. NO - Go to step 6.
6. Turn the ignition switch OFF.
7. Check for ACC system DTCs with the HDS. Is any DTC indicated? YES - Troubleshoot the indicated DTC. NO - Go to step 8.
8. Check for Fuel and Emissions DTCs with the HDS. Is DTC U0104 indicated? YES - Go to step 9. NO - Go to the gauge control module self-diagnostic function (see «SELF-DIAGNOSTIC FUNCTION»(/acura/rl/ii-2004-2008/remont/gauges-instrument-panels/#gauges__self-diagnostic-function) ).
9. Check for VSA system DTCs with the HDS. Is DTC 86 indicated? YES - Go to step 10. NO - Go to the gauge control module self-diagnostic function (see «SELF-DIAGNOSTIC FUNCTION»(/acura/rl/ii-2004-2008/remont/gauges-instrument-panels/#gauges__self-diagnostic-function) ).
10. Check for ACC system DTCs with the HDS. Is DTC 107 indicated? YES - Aim the millimeter wave radar unit (see «MILLIMETER WAVE RADAR UNIT AIMING»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system__millimeter-wave-radar-unit-aiming) ). NO - Go to step 11.
11. Check for CMBS DTCs with the HDS. Is DTC 100 indicated? YES - Troubleshoot the indicated DTC. NO - Go to the ACC system troubleshooting (No DTC indication) (see «ADAPTIVE CRUISE CONTROL (ACC) SYSTEM TROUBLESHOOTING (NO DTC INDICATION)»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). If OK, replace the ACC unit (see «DISTANCE SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ).

Scheme 105

1. Do the gauge control module self-diagnostic function (see «SELF-DIAGNOSTIC FUNCTION»(/acura/rl/ii-2004-2008/remont/gauges-instrument-panels/#gauges__self-diagnostic-function) ). Is the gauge control module OK? YES - Go to step 2. NO - Substitute a known-good gauge control module and recheck. If the problem goes away, replace the original gauge control module (see «GAUGE CONTROL MODULE REPLACEMENT»(/acura/rl/ii-2004-2008/remont/gauges-instrument-panels/#gauges__gauge-control-module-replacement) ).
2. Test the ACC switch (see «CRUISE CONTROL COMBINATION SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). Is the switch OK? YES - Go to step 3. NO - Replace the cruise control combination switch (see «CRUISE CONTROL COMBINATION SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ).
3. Turn the ignition switch ON (II).
4. Measure the voltage between the cruise control combination switch 20P connector No. 13 terminal and body ground. Is there about 5 V? YES - Repair an open in the wire between the cruise control combination switch and body ground. NO - Repair an open in the wire between the cruise control combination switch and the gauge control module.

Scheme 106

1. Do the gauge control module self-diagnostic function (see «SELF-DIAGNOSTIC FUNCTION»(/acura/rl/ii-2004-2008/remont/gauges-instrument-panels/#gauges__self-diagnostic-function) ). Is the gauge control module OK? YES - Go to step 2. NO - Substitute a known-good gauge control module and recheck. If the problem goes away, replace the original gauge control module (see «GAUGE CONTROL MODULE REPLACEMENT»(/acura/rl/ii-2004-2008/remont/gauges-instrument-panels/#gauges__gauge-control-module-replacement) ).
2. Remove the driver's airbag (see «DRIVER'S AIRBAG REPLACEMENT»(/acura/rl/ii-2004-2008/remont/airbag/#srs-supplemental-restraint-system) ).
3. Disconnect the 20P connector (A) from the cable reel.
4. Turn the ignition switch ON (II).
5. Watch the ACC activation indicator. Does the ACC activation indicator go off? YES - Test the cruise control combination switch (see «CRUISE CONTROL COMBINATION SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ). NO - Repair a short to ground in the wire between the cruise control combination switch and the gauge control module.

Scheme 107

Scheme 108

1. Remove the upper grille (see «UPPER GRILLE REPLACEMENT»(/acura/rl/ii-2004-2008/remont/exteriorinterior-trim/#exterior-trim__upper-grille-replacement) ).
2. Disconnect the 5P connector (A) from the millimeter wave radar unit (B).
3. Remove the bolts and the millimeter wave radar unit. NOTE: Go to step 7 if it is not necessary to disassemble the millimeter wave radar unit and main bracket (C).
4. Loosen the aiming bolts (A) a little at a time, and remove the millimeter wave radar unit (B) from the main bracket (C). NOTE: Do not disassemble the millimeter wave radar unit. If you disassemble the main bracket, always use new screw grommets (D).
5. Install new screw grommets on the millimeter wave radar unit. Position the left side grommet grooves (E) horizontally, and position the right side grommet groove (E) vertically.
6. Tighten the main bracket bolts a little at a time until the clearance between the millimeter wave radar unit and the main bracket is 0.43-0.47 in. (11 - 12 mm) (F). Make sure the millimeter wave radar unit is parallel with the main bracket.
7. Clean the surface of the millimeter wave radar unit (G), then install it in the reverse order of removal.
8. Aim the millimeter wave radar unit (see «MILLIMETER WAVE RADAR UNIT AIMING»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system__millimeter-wave-radar-unit-aiming) ).

Scheme 109

Scheme 110

1. Remove the driver's airbag (see «DRIVER'S AIRBAG REPLACEMENT»(/acura/rl/ii-2004-2008/remont/airbag/#srs-supplemental-restraint-system) ).
2. Disconnect the 20P connector (A) from the cable reel.
3. Check for continuity between the terminals in each switch position as shown.
4. If the continuity is not as specified, replace the cruise control combination switch assembly.

Scheme 111

Scheme 112

1. Remove the steering wheel (see «STEERING WHEEL REMOVAL»(/acura/rl/ii-2004-2008/remont/manual-power-steering/#power-steering-system-electronic-power-steering-system__steering-wheel-removal) ).
2. Remove the steering wheel rear cover (A) and the paddle shift switches (B).
3. Remove the cruise control combination switch assembly (A).
4. Install the parts in the reverse order of removal.

Scheme 113

1. Remove the driver's airbag (see «DRIVER'S AIRBAG REPLACEMENT»(/acura/rl/ii-2004-2008/remont/airbag/#srs-supplemental-restraint-system) ).
2. Disconnect the 20P connector (A) from the cable reel.
3. Check for continuity between the 20P connector No. 5 and No. 14 terminals. There should be continuity with the distance switch pressed. There should be no continuity with the distance switch released.
4. If the continuity is not as specified, replace the cruise control combination switch assembly (see «CRUISE CONTROL COMBINATION SWITCH TEST»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) ).

Scheme 114

1. Remove the glove box (see «GLOVE BOX REMOVAL/INSTALLATION»(/acura/rl/ii-2004-2008/remont/exteriorinterior-trim/#dashboard__glove-box-removalinstallation) ).
2. Remove the passenger's under-dash fuse/relay box (see «PASSENGER'S UNDER-DASH FUSE/RELAY BOX REMOVAL/INSTALLATION»(/acura/rl/ii-2004-2008/remont/body-electrical/#under-dash-fuserelay-box) ).
3. Remove the bolts from the bracket that holds the hands free link control unit, the throttle actuator control module, and the ACC unit (A).
4. Disconnect the connectors from the control units.
5. Remove the ACC unit from the bracket.
6. Install the unit in the reverse order of removal. NOTE: If a new ACC unit is installed, do the CMBS initial check (DTC 100) (see «DTC 100: CMBS INITIAL CHECK INCOMPLETE»(/acura/rl/ii-2004-2008/remont/collisionavoidance/#collision-mitigation-brake-system-cmbs__dtc-100-cmbs-initial-check-incomplete) ).

Millimeter Wave Radar Unit Aiming

Special Tools Required

Radar aimer set 070AJ-SDAA100

Prepare the items shown

Scheme 115

1. HDS
2. Level (commercially available)
3. Tape measure and scale
4. Felt-tip pen
5. Tape

Note. If the millimeter wave radar unit is removed or replaced, or if a millimeter wave radar unit aiming error occurs, aim the millimeter wave radar unit. Incomplete aiming, an aiming error, or dust or dirt on the radar unit surface causes the adaptive cruise control (ACC) indicator to come on.

1. Millimeter wave radar unit aiming incomplete: DTC 107
2. Millimeter wave radar unit aiming error: DTC 63
3. Millimeter wave radar unit or emblem surface is contaminated with dust, dirt, ice, or snow: DTC 105

Before Aiming

1. Aiming the millimeter wave radar unit requires the HDS.
2. Clean the surface of the millimeter wave radar unit.
3. Make sure the vehicle has no aftermarket suspension.
4. Make sure all the tire sizes are correct and that their pressure is correct.
5. Make sure the fuel tank is full.
6. Remove all baggage from the vehicle except the spare tire and the tool kit.
7. Make sure the steering wheel is straight ahead, and do not turn it after setting the vehicle.
8. Shift transmission lever into P, and apply the parking brake.
9. Make sure the upper grille and the front bumper are installed correctly.
10. Park the vehicle on level ground in a wide open space to avoid misadjusting caused by reflecting objects. The space needs to be 32.8 ft (10 m) in front, 13.1 ft (4 m) in width and 4.9 ft (1.5 m) in height.
11. If NO TARGET is not indicated even when there are no objects for 33 ft (10 m) in front vehicle, check for reflecting objects in front of the vehicle.

Note. When the millimeter wave radar unit is adjusted on ground that has more than 1 degree of horizontal slope (drainage slope), the vertical aiming cannot be adjusted correctly. Check the levelness of the ground, and adjust the angle of millimeter wave radar unit to be parallel to that of the ground, lay a ruler (at least 12") or other flat straight object on the ground and put the level on top to confirm the levelness of the ground.

Vertical Aiming

Note. When the millimeter wave radar unit is adjusted on ground that has more than 1 degree of horizontal slope (drainage slope), the vertical aiming cannot be adjusted correctly. Check the levelness of the ground, and adjust the angle of millimeter wave radar unit to be parallel to that of the ground, lay a ruler (at least 12") or other flat straight object on the ground and put the level on top to confirm the levelness of the ground.

Scheme 116

1. Remove the upper grill cover (see «UPPER GRILLE COVER REPLACEMENT»(/acura/rl/ii-2004-2008/remont/exteriorinterior-trim/#exterior-trim__upper-grille-cover-replacement) ).
2. Put the level (A) (commercially available) on the aiming pad (B) of the millimeter wave radar unit.
3. Turn the vertical adjusting bolt (C) on the driver's side with a screwdriver, and adjust the angle of millimeter wave radar unit so that the air bubble in the level is centered.

Scheme 117

Scheme 118

Scheme 119

Scheme 120

Scheme 121

Scheme 122

Scheme 123

Scheme 124

Scheme 125

Scheme 126

Scheme 127

Scheme 128

Scheme 129

Scheme 130

Scheme 131

1. Park the vehicle on level ground with at least this much open space around it: 32.8 ft (10 m) in front, 13.1 ft (4 m) in width, and 4.9 ft (1.5 m) in height.
2. Make sure there are no reflecting objects or anything in this range.
3. Check the tire pressures, and adjust the pressures to the specified value if need.
4. Put a person or an object equivalent to the driver's weight in the driver's seat. Setting the Distance between the Target and the Vehicle Horizontal Aiming NOTE: When marking on the floor, use suitable tape to mark the exact locations.
5. Adjust the tip of the height rod (B) on the target to the center of the "A" emblem (A).
6. Place the centering stand under the rear tow hook, then mark the floor at the centerline of the tool.
7. At the front of the vehicle, slide the gas strut holder and the cord through the slot in the centering stand, then slide the strut to the rear of the vehicle.
8. Position the gas strut holder between the rear tow hook and the mark on the floor.
9. Place the centering stand under the hole in the front lift pad.
10. With the target and the height rod aligned with the cord, move the target out in front of the vehicle until the cord is fully extended (16.5 ft, 5 m). Position the cord at the centerline of the centering stand.
11. Contact the HDS to the data link connector (A).
12. Turn the ignition switch ON (II).
13. Check for DTCs with the HDS. NOTE: If DTC 61 or DTC 62 is indicated, troubleshoot the indicated DTC first.
14. Start the engine.
15. Turn the ACC switch (A) ON.
16. Select ADAPTIVE CRUISE CONTROL (ACC) from DRIVING SUPPORT menu. Select RADAR AIMING from ADJUSTMENT menu, the MID will indicate the number "4" on its display for 2 seconds then display "NO TARGET".
17. Make sure the MID indicates "NO TARGET" on its display. NOTE: When the radar is aimed correctly the MID indicates "NO TARGET". If this is not indicated there is an unwanted radar reflection in front of the vehicle in the range of the radar.
18. Confirm the result of the horizontal auto aiming following the onscreen instructions of the HDS. NOTE: The result of all auto aiming can be confirmed by the HDS, by the figure and words displayed on the MID, or by the brake lights illuminating. When the figure is not in the range 100 ± 2 or a tone is sounded by the vehicle when the aiming point is out of specification, or when the brake lights do not come on, the auto aiming is not completed correctly. If DTC 120, 121, 122, 123, or 124 is indicated, the aiming target is not set correctly. Reset the aiming target.
19. If the radar is not aligned in the range where the auto aiming works correctly, turn the horizontal adjusting bolt (A) and adjust the direction of the millimeter wave radar unit until it comes to within 100 ± 1, as confirmed by the HDS, the MID display, or by the brake lights illuminating. NOTE: Do not work in front of the millimeter wave radar unit (in the range of radar irradiation), because it detects your tools and your body, and the aiming cannot be completed correctly. Example 1: Out of the auto aiming range The MID display "106" means the radar aim is 0.6 degrees out of the range where auto aiming can work. Example 2: In the auto aiming range The MID display "100" means auto aiming can work.
20. After adjustment, confirm the MID display and the brake lights illuminating, and finalize the horizontal aiming. (End the aiming process on the HDS). NOTE: If the radar aim is within specification, the MID displays "RADAR OK 100". If the radar aiming is incomplete (for example, the ACC switch was pressed before the aiming was completed) the MID displays the out-of-range value (example, "106"). If you need to cancel the aiming, turn the ignition switch off.
21. After aiming, clear the DTCs with the HDS.

DTCs (if the aiming is incomplete)

Note. If the aiming is incomplete, the MID indicates a DTC. The ACC unit does not store the DTC, and you cannot read the DTCs with the HDS, so note the DTC before cycling the ignition key.

DTC CHART

Brake Fluid Pressure Sensor Replacement

Note. Do not spill brake fluid on the vehicle; it may damage the paint; if brake fluid gets on the paint, wash it off immediately with water. To prevent dripping brake fluid, cover disconnected hose joints with rags or shop towels. Do not twist the brake hose and line when removed.

Scheme 132

Scheme 133

1. Drain the brake fluid.
2. Disconnect the 3P connector (BLU) (A) from the right front pressure sensor (B).
3. Disconnect the 3P connector (GRY) (C) from the left front pressure sensor (D).
4. Remove the brake lines (E) from the 4-way joint (F).
5. Remove the brake 4-way joint.
6. Remove the right (A) and left (B) pressure sensors from the brake 4-way joint (C).
7. Install the parts in the reverse order of removal with new O-rings (D). NOTE: Make sure the connector colors and pressure sensor locations are correct.
8. After installation, refill the brake fluid, and bleed the brake system (see «BRAKE SYSTEM BLEEDING»(/acura/rl/ii-2004-2008/remont/mechanical-hydraulic/#conventional-brake-components__brake-system-bleeding) ).
9. Do these checks: Check the brake hose and line joint for leaks, and tighten if necessary. Check the brake hoses for interference and twisting.
10. Connect the HDS to the data link connector.
11. Turn the ignition switch ON (II).
12. Turn the adaptive cruise control (ACC) switch ON.
13. Clear the DTCs with the HDS.
14. Select ADAPTIVE CRUISE CONTROL (ACC) from ACC/CMBS menu, then enter FUNCTION TEST.
15. Activate BRAKE ACTUATOR 3 from the FUNCTION TEST. NOTE: BRAKE ACTUATOR 3 operates the adaptive cruise control brake in this order (pressurization-stop-pressurization-stop). It takes about 6 seconds.
16. Check for DTCs with the HDS. If there is a DTC, go to the «INDICATED DTCS TROUBLESHOOTING»(/acura/rl/ii-2004-2008/remont/cruise-control-systems/#adaptive-cruise-control-system) . If there is no DTC, the brake pressure sensor replacement is complete.

See also:
• DLC CIRCUIT TROUBLESHOOTING
• 100
• DTC TROUBLESHOOTING INDEX
• SELF-DIAGNOSTIC FUNCTION
• TRANSMISSION RANGE SWITCH TEST
• HIGH MOUNT BRAKE LIGHT REPLACEMENT
• GENERAL TROUBLESHOOTING INFORMATION
• ABS/VSA INDICATOR
• BRAKE PEDAL AND BRAKE PEDAL POSITION SWITCH ADJUSTMENT
• POWER RELAY TEST
• MASTER CYLINDER INSPECTION
• BRAKE PEDAL POSITION SWITCH SIGNAL CIRCUIT TROUBLESHOOTING
• UPPER GRILLE REPLACEMENT
• SUBSTITUTING THE PCM
• WHEEL ALIGNMENT
• GAUGE CONTROL MODULE REPLACEMENT
• DRIVER'S AIRBAG REPLACEMENT
• STEERING WHEEL REMOVAL
• GLOVE BOX REMOVAL/INSTALLATION
• PASSENGER'S UNDER-DASH FUSE/RELAY BOX REMOVAL/INSTALLATION
• UPPER GRILLE COVER REPLACEMENT
• BRAKE SYSTEM BLEEDING
• DTC TROUBLESHOOTING
• 10
• 11
• 12
• 13
• 14
• 21
• 23
• 25
• 43
• 46
• 47
• 50
• 62
• 63
• 81
• 83
• 84
• 85
• 86
• 87
• 88
• 89
• 90
• 91
• 92
• 93
• 94
• 95
• 96
• 99
• 101
• 105
• 107
• ADAPTIVE CRUISE CONTROL (ACC) INDICATOR (AMBER) DOES NOT GO OFF
• BRAKE FLUID PRESSURE SENSOR REPLACEMENT
• MILLIMETER WAVE RADAR UNIT AIMING