Collision Mitigation Brake System (cmbs) Acura RL II рестайлинг

Scheme 1

Scheme 2

CMBS Indicator

If the system is OK, the CMBS indicator goes off 2 seconds after turning the ignition switch ON (II). The CMBS indicator comes on when the adaptive cruise control (ACC) unit detects a problem in the system.

Note. The ACC indicator indicates problems related with the ACC system and the CMBS. The CMBS indicator only indicates its system problems. The CMBS works with related systems such as the VSA system. If these related systems have a problem, the CMBS does not operate. In this case, the CMBS indicator and the related system indicator come on.

Scheme 3

When a problem is detected by the self-diagnostic function, the CMBS stops operating, turns on the CMBS indicator, indicates the problem on the MID, and stores the DTC.

CMBS OFF Switch

Press and hold the CMBS OFF switch for at least a second to turn the CMBS off and on.

CMBS Indication

1. If the system is OK, the CMBS indicator comes on for 5 seconds after turning the ignition switch ON (II) with the CMBS OFF switch on.
2. When the system is activated, the word "BRAKE" is indicated on the MID and the warning buzzer sounds. First stage, BRAKE indicator and buzzer Second stage, BRAKE indicator, buzzer, light braking, and light seat belt tension Third stage, BRAKE indicator, buzzer, strong braking, and strong seat belt tension
3. If the system stops operating because of a problem, the MID indicates the problem.

ACC Unit

The ACC unit controls the brake and warning when the system recognizes the danger of a collision. The ACC unit has a self-diagnostic function. If the system detects a problem, it stops the CMBS, and turns on the CMBS indicator.

CMBS Initial Check

The ACC unit turns on the CMBS indicator if the CMBS initial check is not completed.

Note. For proper CMBS operation, if the ACC unit or the VSA modulator-control unit is replaced, do DTC 100: CMBS INITIAL CHECK INCOMPLETE .

Millimeter Wave Radar

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

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

The millimeter wave radar also has an error detect function, and sends a signal to the ACC unit if an error is detected.

How to Troubleshoot DTCs

Check and clear the DTCs with the HDS.

Note. When both the ACC and CMBS indicators come on, do the ACC system troubleshooting first (except DTC 100).

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 CMBS 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.
4. The ACC system and the CMBS may sometimes stop working 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 88: ACC indicator does not come on, CMBS indicator comes on

The millimeter wave radar overheats, the power supply voltage for the millimeter wave radar is low, or there is a communication error between the ACC unit and the millimeter wave radar.

DTC 95: ACC indicator does not come on, CMBS indicator comes on

Battery voltage is too high.

DTC 96: ACC indicator does not come on, CMBS indicator comes on

Battery voltage is too low.

DTC 97: ACC indicator does not come on, CMBS indicator comes on

Extensive driving on a rough road or the ignition switch is turned ON (ID/OFF.

DTC 102: ACC indicator does not come on, CMBS indicator comes on

Parking brake not fully released, or driving with the parking brake stuck.

Scheme 4

1. With the ignition switch is in LOCK (0), connect the HDS to the data link connector (DLC) (A) under the left side of the dashboard.
2. Turn the ignition switch to 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-2008-2012/remont/testing-diagnostics/#pgm-fi-system__dlc-circuit-troubleshooting) ).
4. Follow the prompts on the HDS to display the DTC(s) on the screen. After determining the DTC, refer to «DTC TROUBLESHOOTING»(/acura/rl/ii-2008-2012/remont/collisionavoidance/#collision-mitigation-brake-system-cmbs) . NOTE: See the HDS Help menu for specific instructions.

How to Clear DTCs

Note. You cannot clear the DTCs manually.

Scheme 5

1. With the ignition switch is in LOCK (0), connect the HDS to the data link connector (DLC) (A) under the left side of the dashboard.
2. Turn the ignition switch to 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-2008-2012/remont/testing-diagnostics/#pgm-fi-system__dlc-circuit-troubleshooting) ).
4. Clear the DTC(s) by following the screen prompts on the HDS. NOTE: See the HDS Help menu for specific instructions. Some DTCs cannot be cleared until the radar aiming is complete.

DTC Troubleshooting Index

DTC TROUBLESHOOTING TABLE

Note. When both the ACC and CMBS indicators come on, do the ACC system troubleshooting first (except DTC 100).

CMBS INDICATOR REFERENCE TABLE

Note. When both the ACC and CMBS indicators come on, do the ACC system troubleshooting first (except DTC 100).

Symptom Troubleshooting Index

SYMPTOM TROUBLESHOOTING TABLE

System Description

The collision mitigation brake system (CMBS), anticipates collisions and assists brake operation to reduce the impact on occupants and vehicle damage. The system works in combination with the e-pretensioners, which retract the seat belts in anticipation of impact.

CMBS Operation

1. Warnings are both audible (warning buzzer) and visual (MID)
2. Evasive action support and collision-speed reduction by brake control

Scheme 6

Main Functions Of CMBS

1. When a collision is about to happen and the relative speed (the speed difference from the object ahead) is greater than 9 mph (15 km/h), the system provides warnings (audible and visual) and brake control.
2. When approaching a object ahead and the distance to the vehicle is very close, the system provides the collision warning (1st stage) by MID indication and buzzer sounding.
3. When the closing distance continues to decrease and there is a high risk of collision, the system applies light braking (2nd stage) with the 1st stage warning.
4. When the system judges that a collision is imminent, the system activates emergency brake control.

CMBS Control

The CMBS is operated by the ACC unit. The CMBS has the following functions

Obstacle Determination Function

The system determines the potential for collision by the distance from the vehicle ahead and the relative speed based on the millimeter wave radar and the predictable course calculated by the driving conditions (wheel speed and yaw rate).

Warning Function

When there is a high risk of collision, the system sends warning directions to the gauge control module and warns by both audible and visual means.

Brake Control Function

When there is a high risk of collision, the system sends brake directions to the VSA modulator-control unit and controls braking action.

CMBS Activation Conditions

The system might activate (warn the driver, apply the brakes) when it detects or encounters these situations

1. Metallic projections on the road
2. Metallic manhole and drain covers
3. Signs and guardrails ahead
4. Low overpasses and narrow gates
5. Approaching vehicles that are turning left or right
6. Passing slower vehicles ahead

The system might not activate (no warning or intervention) when it detects or encounters these situations

1. Low-speed, heavy traffic (such as in a traffic jam)
2. Being cut-off by a slower vehicle
3. Approaching a vehicle stopped at an angle
4. Driving on curves
5. Approaching a bicycle or moped
6. Dirt or snow stuck on the front radar cover
7. Heavy rain or snow

When the CMBS activates, it sounds and feels just like ABS activation.

Scheme 7

Scheme 8

WIRE TEST CONDITION REFERENCE TABLE

Scheme 9

Scheme 10

DTC 20: Steering Angle Sensor Malfunction

Note. Before doing this troubleshooting procedure, check the steering angle sensor installation (see STEERING ANGLE SENSOR REPLACEMENT ).

1. Turn the ignition switch to ON (II).
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. Turn the ignition switch to LOCK (0), then turn the ignition switch to ON (II).
5. Turn the steering wheel from lock-to-lock.
6. Check the DTCs with the HDS. Is DTC 73 indicated? YES - Go to step 7 . NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.
7. Check the CALIBRATION STATUS OF STEERING ANGLE SENSOR in the DATA LIST with the HDS. Is NOT COMPLETE indicated? YES - Do the steering neutral position memorization procedure (see «VSA SENSOR NEUTRAL POSITION MEMORIZATION»(/acura/rl/ii-2008-2012/remont/anti-locktraction-control/#vsa-vehicle-stability-assist-system-components__vsa-sensor-neutral-position-memorization) ). NO - Faulty steering angle sensor; replace the steering angle sensor (see «STEERING ANGLE SENSOR REPLACEMENT»(/acura/rl/ii-2008-2012/remont/anti-locktraction-control/#vsa-vehicle-stability-assist-system-components__steering-angle-sensor-replacement) ).

DTC 26: Steering Angle Sensor Adherence Failure

Note. Before doing this troubleshooting procedure, check the steering angle sensor installation.

1. Turn the ignition switch to ON (II).
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. Check the STEERING ANGLE in the DATA LIST with the HDS, turn the steering wheel from lock-to-lock. Are any value change? YES - Faulty steering angle sensor; replace the steering angle sensor (see «STEERING ANGLE SENSOR REPLACEMENT»(/acura/rl/ii-2008-2012/remont/anti-locktraction-control/#vsa-vehicle-stability-assist-system-components__steering-angle-sensor-replacement) ). NO - Faulty ACC unit; replace the ACC unit (see «ADAPTIVE CRUISE CONTROL (ACC) UNIT REMOVAL/INSTALLATION»(/acura/rl/ii-2008-2012/remont/cruise-control-systems/#adaptive-cruise-control-acc-system) ).

DTC 34, 35, 36: Master Cylinder Brake Fluid Pressure Sensor Circuit Open/Short; Master Cylinder Brake Fluid Pressure Sensor Center Position Error; Master Cylinder Brake Fluid Pressure Sensor Shift Error

1. Turn the ignition switch to 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. Press the brake pedal.
5. 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 6 .
6. Check for DTCs with the HDS. Is DTC 34, 35 or 36 indicated? YES - Go to step 7 . NO - Troubleshoot the indicated DTC.
7. With the brake pedal released, check the master cylinder brake fluid pressure voltage (BRAKE P) with the HDS. Is there about 0.5 V? YES - Go to step 8 . NO - Check the VSA system.
8. Test the brake booster (see «BRAKE BOOSTER TEST»(/acura/rl/ii-2008-2012/remont/mechanical-hydraulic/#conventional-brake-components) ).
9. Press the brake pedal with about 314 N (32 kgf, 70.6 lbf) pressure.
10. Check the master cylinder brake fluid pressure voltage (BRAKE P) with the HDS. Is there about 2.5 V? YES - Go to step 11 . NO - Check the VSA system.
11. 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 - Check for loose or poor connections. If OK, replace the ACC unit (see «ADAPTIVE CRUISE CONTROL (ACC) UNIT REMOVAL/INSTALLATION»(/acura/rl/ii-2008-2012/remont/cruise-control-systems/#adaptive-cruise-control-acc-system) ). NO - Go to step 12 .
12. Check for DTCs with the HDS. Is DTC 60, 110, or 111 indicated? YES - Troubleshoot the indicated DTC(s). NO - Troubleshoot the brake pedal position switch signal circuit (see «BRAKE PEDAL POSITION SWITCH SIGNAL CIRCUIT TROUBLESHOOTING»(/acura/rl/ii-2008-2012/remont/testing-diagnostics/#idle-control-system) ).

DTC 64: CMBS Operation Error (Excessive Operation)

Note. If the CMBS operates frequently, DTC 64 is stored.

1. Remove the upper grille (see «UPPER GRILLE REPLACEMENT»(/acura/rl/ii-2008-2012/remont/exteriorinterior-trim/#exterior-trim) ).
2. Inspect the frame for warpage, and check the installation of the millimeter wave radar and the main bracket. Is the installation and the frame OK? YES - Go to step 3 . NO - Reinstall the components correctly, or replace if damaged, then go to step 3 .
3. Turn the ignition switch to ON (II).
4. Aim the millimeter wave radar (see «MILLIMETER WAVE RADAR AIMING»(/acura/rl/ii-2008-2012/remont/cruise-control-systems/#adaptive-cruise-control-acc-system) ).
5. Clear the DTCs with the HDS.
6. Turn the adaptive cruise control (ACC) switch ON.
7. Watch the ACC and CMBS indicators. Do both indicators come on? YES - Go to step 8 . NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.
8. Clear the DTCs with the HDS.
9. Watch the CMBS indicator. Does the CMBS indicator come on? 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 64 indicated? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «ADAPTIVE CRUISE CONTROL (ACC) UNIT REMOVAL/INSTALLATION»(/acura/rl/ii-2008-2012/remont/cruise-control-systems/#adaptive-cruise-control-acc-system) ). NO - Troubleshoot the indicated DTC.

DTC 100: CMBS Initial Check Incomplete

Note. The CMBS initial check function checks the communication between the adaptive cruise control (ACC) unit and VSA modulator-control unit. If the CMBS initial check is incomplete, the ACC and CMBS indicators come on. For the CMBS to operate properly, always do the CMBS initial check after replacing the ACC unit or the VSA modulator-control unit.

1. Turn the ignition switch to ON (II).
2. Watch the VSA indicator. Does the VSA indicator come on? YES - Troubleshoot the indicated VSA system DTC(s). NO - Go to step 3 .
3. Check for VSA system DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated VSA system DTC(s). NO - Go to step 4 .
4. Start the engine.
5. Select CMBS from the DRIVING SUPPORT menu, then enter the MISCELLANEOUS TEST.
6. Do the CMBS brake forced operation.
7. Watch the ACC and CMBS indicators. Do both indicators come on? YES - Go to step 8 . NO - The system is OK at this time. The CMBS initial check is complete.
8. Check for ACC system DTCs with the HDS. Are any DTCs except DTC 100 indicated? YES - Troubleshoot the indicated DTC(s). NO - Check for loose or poor connections. If OK, replace the ACC unit (see «ADAPTIVE CRUISE CONTROL (ACC) UNIT REMOVAL/INSTALLATION»(/acura/rl/ii-2008-2012/remont/cruise-control-systems/#adaptive-cruise-control-acc-system) ).

DTC 103: CMBS Brake Control Prohibition

1. Turn the ignition switch to ON (II).
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. Watch the CMBS indicator. Does the CMBS indicator come on? YES - Go to step 5 . NO - The system is OK at this time.
5. Check for adaptive cruise control (ACC) system DTCs with the HDS. Is DTC 103 indicated? YES - Check for loose or poor connections. If OK, replace the ACC unit (see «ADAPTIVE CRUISE CONTROL (ACC) UNIT REMOVAL/INSTALLATION»(/acura/rl/ii-2008-2012/remont/cruise-control-systems/#adaptive-cruise-control-acc-system) ). NO - Troubleshoot the indicated DTC.

Scheme 11

1. Clear the DTCs with the HDS.
2. Turn the ignition switch to ON (II).
3. Check for DTCs with the HDS. Is DTC 117 indicated? YES - Go to step 4 . NO - Intermittent failure. The system is OK at this time. Check for loose or poor connections.
4. Check for VSA system DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated VSA system DTC(s). NO - Go to step 5 .
5. Disconnect the dashboard wire harness 5P connector from the steering angle sensor (see «STEERING COLUMN REMOVAL AND INSTALLATION»(/acura/rl/ii-2008-2012/remont/manual-power-steering/#steering) ).
6. Disconnect the dashboard wire harness 20P connector from the adaptive cruise control (ACC) unit (see «ADAPTIVE CRUISE CONTROL (ACC) UNIT REMOVAL/INSTALLATION»(/acura/rl/ii-2008-2012/remont/cruise-control-systems/#adaptive-cruise-control-acc-system) ).
7. Check for continuity between ACC unit 20P connector terminal No. 10 and steering angle sensor 5P connector terminal No. 2, and between ACC unit 20P connector terminal No. 20 and steering angle sensor 5P connector terminals No. 4. Is there continuity? YES - Faulty ACC unit; replace the ACC unit (see «ADAPTIVE CRUISE CONTROL (ACC) UNIT REMOVAL/INSTALLATION»(/acura/rl/ii-2008-2012/remont/cruise-control-systems/#adaptive-cruise-control-acc-system) ). NO - Open in the dashboard wire harness; replace the dashboard wire harness.

CMBS Indicator Does Not Go Off

1. Turn the ignition switch to ON (II).
2. Press and hold the CMBS OFF switch for a second or more to turn off the system.
3. Watch the CMBS indicator. Does the CMBS indicator go off? YES - The system is OK at this time. NO - Go to step 4 .
4. Turn the ignition switch to LOCK (0).
5. Connect the HDS to the data link connector.
6. Clear the DTCs with the HDS.
7. Turn the ignition switch to ON (II).
8. Check for the adaptive cruise control (ACC) system, VSA, and PCM DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated DTC(s). NO - Go to step 9 .
9. Start the engine, and wait at least 2 seconds.
10. Watch the CMBS indicator. Does the CMBS indicator stay off? YES - The system is OK at this time. NO - Go to step 11 .
11. Stop the engine.
12. Check for ACC system DTCs with the HDS. Are any DTCs indicated? YES - Troubleshoot the indicated DTC(s). NO - Test the CMBS OFF switch (see «CMBS OFF SWITCH TEST/REPLACEMENT»(/acura/rl/ii-2008-2012/remont/collisionavoidance/#collision-mitigation-brake-system-cmbs) ). If the switch is OK, do the gauge control module self-diagnostic function (see «SELF-DIAGNOSTIC FUNCTION»(/acura/rl/ii-2008-2012/remont/gauges-instrument-panels/#gauges__self-diagnostic-function) ).

Scheme 12

Scheme 13

Scheme 14

1. Remove the instrument fascia (see «INSTRUMENT FASCIA REMOVAL/INSTALLATION»(/acura/rl/ii-2008-2012/remont/exteriorinterior-trim/#dashboard__instrument-fascia-removalinstallation) ).
2. Remove the screws and the multi-switch (A).
3. Check for continuity between the terminals in each CMBS OFF switch position according to the table below.
4. If the continuity is not as specified, replace the switch.

See also:
• DLC CIRCUIT TROUBLESHOOTING
• 11
• 12
• 13
• 14
• 21
• 23
• 25
• 30
• 62
• 63
• 90
• 105
• 107
• SELF-DIAGNOSTIC FUNCTION
• STEERING ANGLE SENSOR REPLACEMENT
• VSA SENSOR NEUTRAL POSITION MEMORIZATION
• BRAKE BOOSTER TEST
• BRAKE PEDAL POSITION SWITCH SIGNAL CIRCUIT TROUBLESHOOTING
• UPPER GRILLE REPLACEMENT
• STEERING COLUMN REMOVAL AND INSTALLATION
• INSTRUMENT FASCIA REMOVAL/INSTALLATION
• DTC 100: CMBS INITIAL CHECK INCOMPLETE
• DTC TROUBLESHOOTING
• 20
• 26
• 34
• 64
• 103