Active Stability Control System (Asc): Other Mitsubishi Outlander III

HOW TO READ DATA LIST

1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Select "System Select."
4. Select "ABS/ASC/ASTC" from the system list, and select the "OK" button.
5. Select "Data List."

CHECK OF FREEZE FRAME DATA

The freeze frame data can be checked by using the scan tool.

When detecting fault and storing the DTC, the ECU connected to CAN bus line obtains the data before the determination of the DTC and the data when the DTC is determined, and then stores the ECU status of that time. By analyzing each data from scan tool, the troubleshooting can be performed more efficiently. The displayed items are as the table below.

Display item list

FREEZE FRAME DATA

FAIL-SAFE FUNCTIONS

ASC-ECU constantly monitors the input and output signals. If an error is detected in the system, ASC-ECU sends a fail signal and the corresponding indicator light is illuminated or blinks. Various controls are processed depending on the cause of malfunction as shown below.

Illumination condition of warning light and display in case of failure

FAIL-SAFE CHART

Under EBD, ABS, stability control, HSA and TCL control in case of failure

FAIL-SAFE CHART

Code No. C102A: MUTUAL MONITORING OF RL WHEEL SPEED SENSOR

PROBABLE CAUSES

1. Damaged wiring harness and connectors
2. External noise interference
3. Malfunction of wheel speed sensor
4. ASC-ECU malfunction
5. Excessive gap between the wheel speed sensor and the magnetic encoder for wheel speed detection
6. Adhesion of foreign materials on the wheel speed sensor
7. Adhesion of foreign materials on the magnetic encoder for wheel speed detection
8. Wheel bearing malfunction
9. Improper installation of the wheel speed sensor
10. Deformation of the magnetic encoder for wheel speed detection
11. Disturbance of magnetization pattern for magnetic encoder for wheel speed detection
12. Missing teeth of the magnetic encoder for wheel speed detection

1. Damaged wiring harness and connectors
2. External noise interference
3. Malfunction of wheel speed sensor
4. ASC-ECU malfunction
5. Excessive gap between the wheel speed sensor and the magnetic encoder for wheel speed detection
6. Adhesion of foreign materials on the wheel speed sensor
7. Adhesion of foreign materials on the magnetic encoder for wheel speed detection
8. Wheel bearing malfunction
9. Improper installation of the wheel speed sensor
10. Deformation of the magnetic encoder for wheel speed detection
11. Disturbance of magnetization pattern for magnetic encoder for wheel speed detection
12. Missing teeth of the magnetic encoder for wheel speed detection

1. Damaged wiring harness and connectors
2. External noise interference
3. Malfunction of wheel speed sensor
4. ASC-ECU malfunction
5. Excessive gap between the wheel speed sensor and the wheel speed detection encoder
6. Adhesion of foreign materials on the wheel speed sensor
7. Adhesion of foreign materials on the wheel speed detection encoder
8. Wheel bearing malfunction
9. Improper installation of the wheel speed sensor
10. Deformation of the wheel speed detection encoder
11. Disturbance of magnetization pattern for wheel speed detection encoder
12. Missing teeth of the wheel speed detection encoder

1. Damaged wiring harness and connectors
2. External noise interference
3. Malfunction of wheel speed sensor
4. ASC-ECU malfunction
5. Excessive gap between the wheel speed sensor and the wheel speed detection encoder
6. Adhesion of foreign materials on the wheel speed sensor
7. Adhesion of foreign materials on the wheel speed detection encoder
8. Wheel bearing malfunction
9. Improper installation of the wheel speed sensor
10. Deformation of the wheel speed detection encoder
11. Disturbance of magnetization pattern for wheel speed detection encoder
12. Missing teeth of the wheel speed detection encoder

1. ASC-ECU malfunction

1. Incorrect brake pedal height
2. Incorrect adjustment of the stoplight switch
3. Master cylinder malfunction
4. Brake booster malfunction
5. ASC-ECU malfunction

1. Incorrect adjustment of brake pedal height
2. Master cylinder malfunction
3. Brake booster malfunction
4. Incorrect installation position of stoplight switch
5. Stoplight switch malfunction
6. Brake drag
7. ASC-ECU malfunction

Scheme 46

1. STEP 1. Using scan tool MB991958, diagnose the CAN bus line. Use scan tool MB991958 to diagnose the CAN bus lines. Q: Is the check result normal? YES: Go to Step 3 . NO: Repair the CAN bus lines (Refer to «CAN BUS DIAGNOSTICS TABLE»(ref-593004-S22202362482014011300000) ). On completion, go to Step 2.
2. STEP 2. Diagnostic trouble code recheck after resetting CAN bus lines Q: Is DTC C121E set? YES: Go to Step 3. NO: The procedure is complete.
3. STEP 3. Brake pedal check Refer to «ON-VEHICLE SERVICE/BRAKE PEDAL INSPECTION»(ref-593035-S17719841562014011300000) . Q: Is the check result normal? YES: Go to Step 4. NO: Go to «BRAKE PEDAL INSPECTION»(ref-593035-S17719841562014011300000) .
4. STEP 4. Check whether the other system diagnostic trouble code is set. Refer to «REAR COMBINATION LIGHT/DIAGNOSTIC TROUBLE CODE CHART»(ref-593047-S14720677562014011300000) . Q: Is any DTC set? YES: Repair or replace the rear combination light or rear combination light circuit. NO: Go to Step 5.
5. STEP 5. Check for stoplight switch installation Refer to «ON-VEHICLE SERVICE/BRAKE PEDAL INSPECTION»(ref-593035-S17719841562014011300000) . Q: Is the check result normal? YES: Go to Step 6. NO: Install the stop light switch correctly (Refer to «BRAKE PEDAL»(ref-593035-S14610515972014011300000) ), and then go to Step 10 .
6. STEP 6. Stoplight switch continuity check Remove the stoplight switch (Refer to «BRAKE PEDAL»(ref-593035-S14610515972014011300000) ). Connect the circuit tester (ohms range) to the stop light switch connector terminals No. 1 and No. 2. When no continuity is detected with the plunger pressed from the edge of the outer case by the dimension shown in the illustration and when continuity is detected with the plunger released, the stop light switch is in good condition. Q: Is the check result normal? YES: Go to Step 7. NO: Replace the stop light switch (Refer to «BRAKE PEDAL»(ref-593035-S14610515972014011300000) ), and then go to Step 10 .
7. STEP 7. Brake drag check Check the brake system for drag (Refer to «ON-VEHICLE SERVICE/BRAKE DRAG FORCE CHECK»(ref-593035-S16157005882014011300000) ). Q: Is the check result normal? YES: Go to Step 8. NO: Repair the brake drag, and then go to Step 10 .
8. STEP 8. Brake booster check Refer to «ON-VEHICLE SERVICE/BRAKE BOOSTER OPERATION CHECK»(ref-593035-S38825291152014011300000) . Q: Is the check result normal? YES: Go to Step 9. NO: Replace the brake booster (Refer to «MASTER CYLINDER ASSEMBLY AND BRAKE BOOSTER»(ref-593035-S42418374952014011300000) ), and then go to Step 10 .
9. STEP 9. Check whether the diagnostic trouble code is reset. Erase the DTC. Q: Is DTC C121E set? YES: Replace the hydraulic unit (integrated with ASC-ECU) (Refer to «HYDRAULIC UNIT»(ref-592981-S29861285002014011300000) ). Then go to Step 10. NO: The trouble can be an intermittent malfunction (Refer to «HOW TO USE TROUBLESHOOTING/HOW TO COPE WITH INTERMITTENT MALFUNCTIONS»(ref-592971-S42664974692014011300000) ).
10. STEP 10. Check whether the diagnostic trouble code is reset. Erase the DTC. Q: Is DTC C121E set? YES: Return to Step 1 . NO: The procedure is complete.

Scheme 47

1. Malfunction of the stoplight relay
2. Malfunction of the stoplight
3. Damaged wiring harness and connectors
4. ETACS-ECU malfunction
5. ASC-ECU malfunction

1. Steering wheel sensor malfunction
2. G and yaw rate sensor malfunction
3. Improper installation of wheel speed sensor, steering wheel sensor, or G and yaw rate sensor
4. ASC-ECU malfunction
5. Different steering wheel
6. Wheel alignment not performed

ASC-ECU malfunction

1. Battery failure
2. ASC-ECU malfunction
3. Charging system failed

1. Different hydraulic unit (For delivery to factory)
2. ASC-ECU malfunction

1. Wrong coding
2. Engine control module malfunction
3. ASC-ECU malfunction
4. External noise interference

1. Engine control module malfunction
2. TCM malfunction
3. AWD-ECU malfunction
4. Steering wheel sensor malfunction
5. CAN bus malfunction
6. ASC-ECU malfunction
7. ETACS-ECU malfunction
8. ETACS-ECUs have been interchanged between two vehicles.
9. Connector disconnected or improperly connected
10. Stretched or broken wires

1. Malfunction of the CAN bus
2. Engine control module malfunction
3. ASC-ECU malfunction
4. When the ignition switch is turned to the "ON" position for the first time after the ASC-ECU is replaced.

1. ETACS-ECU or ASC-ECU which was equipped with other vehicle is used.
2. Malfunction of ETACS-ECU
3. ASC-ECU malfunction
4. External noise interference

1. G and yaw rate sensor malfunction
2. ASC-ECU malfunction
3. External noise interference
4. The G and yaw rate sensor for FWD is installed.

1. Improper installation of the G and yaw rate sensor
2. G and yaw rate sensor malfunction
3. Wheel speed sensor malfunction
4. ASC-ECU malfunction
5. External noise interference NOTE: This DTC may be set also when the vehicle is driven on the four-wheel drum tester.

1. Improper installation of the G and yaw rate sensor
2. G and yaw rate sensor malfunction
3. Steering wheel sensor malfunction
4. Improper installation of steering wheel sensor
5. Malfunction of wheel speed sensor
6. ASC-ECU malfunction
7. External noise interference

1. Improper installation of the G and yaw rate sensor
2. Damaged wiring harness and connectors
3. G and yaw rate sensor malfunction
4. ASC-ECU malfunction

ASC-ECU malfunction

1. Damaged wiring harness and connectors
2. G and yaw rate sensor malfunction
3. ASC-ECU malfunction

Scheme 48

1. STEP 1. Using scan tool MB991958, diagnose the CAN bus lines. Use scan tool to diagnose the CAN bus lines. Q: Is the check result normal? YES: Go to Step 2. NO: Repair the CAN bus lines (Refer to «CAN BUS DIAGNOSTICS TABLE»(ref-593004-S22202362482014011300000) ). On completion, go to Step 2.
2. STEP 2. Using scan tool MB991958, check the DTC. Check that the DTC U0125 is set in ASC-ECU. Q: Is DTC U0125 set? YES: Troubleshoot for the DTC (Refer to «DTC U0125: G AND YAW RATE SENSOR MESSAGE TIME-OUT ERROR/MESSAGE ERROR»(ref-592981-S25853512512014011300000) ). Then go to Step 3. NO: Go to Step 3.
3. STEP 3. DTC recheck Q: Is DTC C2114 or C2115 set? YES: Go to Step 4. NO: The procedure is complete.
4. STEP 4. Using scan tool MB991958, check the data list Check the following data list (Refer to «DATA LIST REFERENCE TABLE»(ref-592981-S38335801202014011300000) ). Item 08: Lateral G sensor Item 09: G sensor Item 12: Yaw rate sensor Q: Is the check result normal? YES: Go to Step 12 . NO: Go to Step 5.
5. STEP 5. Connector check: A-03 ASC-ECU connector, C-22 G and yaw rate sensor connector Q: Is the check result normal? YES: Go to Step 6. NO: Repair the connector, and then go to Step 13 .
6. STEP 6. Wiring harness check between A-03 ASC-ECU connector terminal No. 18 and C-22 G and yaw rate sensor connector terminal No. 3 as well as between A-03 ASC-ECU connector terminal No. 19 and C-22 G and yaw rate sensor connector terminal No. 2 Check the communication circuit for open and short circuit. Q: Is the check result normal? YES: Go to Step 7. NO: Repair the wiring harness, and then go to Step 13 .
7. STEP 7. G and yaw rate sensor installation check Check that the G and yaw rate sensor is installed correctly. Q: Is the check result normal? YES: Go to Step 8. NO: Reinstall the G and yaw rate sensor correctly (Refer to «G AND YAW RATE SENSOR»(ref-592981-S13562507192014011300000) ), and then go to Step 13 .
8. STEP 8. Voltage measurement at C-22 G and yaw rate sensor connector Disconnect the C-22 G and yaw rate sensor connector. Turn the ignition switch to the "ON" position. Measure the voltage at the harness side between the terminal No. 1 and the body ground. OK: 6.5 - 16 volt Q: Is the check result normal? YES: Go to Step 11 . NO: Go to Step 9.
9. STEP 9. Voltage measurement at A-03 ASC-ECU connector Disconnect the ASC-ECU connector, connect the ASC check harness (Special tool: MB991997) to the ASC-ECU-side connector and harness-side connector, and then measure at the special tool connector side. Disconnect the C-22 G and yaw rate sensor connector. Turn the ignition switch to the "ON" position. Measure the voltage between the terminal No. 22 and the body ground. OK: 6.5 - 16 volt Q: Is the check result normal? YES: Go to Step 10. NO: Go to Step 12 .
10. STEP 10. Wiring harness check between A-03 ASC-ECU connector terminal No. 22 and C-22 G and yaw rate sensor connector terminal No. 1. Check the power supply circuit for short and open circuit. Q: Is the check result normal? YES: Go to Step 12 . NO: Repair the wiring harness between A-03 ASC-ECU connector terminal No. 22 and C-22 G and yaw rate sensor connector terminal No. 1.
11. STEP 11. Wiring harness check between A-03 ASC-ECU connector terminal No. 29 and C-22 G and yaw rate sensor connector terminal No. 4. Check the ground circuit for open circuit. Q: Is the check result normal? YES: Replace the G and yaw rate sensor (Refer to «G AND YAW RATE SENSOR»(ref-592981-S13562507192014011300000) ) and then go to Step 12. NO: Repair the wiring harness between A-03 ASC-ECU connector terminal No. 29 and C-22 G and yaw rate sensor connector terminal No. 4.
12. STEP 12. Check whether the DTC is reset. Erase the DTC. Drive the vehicle at 12mph (20 km/h) or higher. Q: Is DTC C2114 or C2115 set? YES: Replace the hydraulic unit (integrated with ASC-ECU) (Refer to «HYDRAULIC UNIT»(ref-592981-S29861285002014011300000) ), and then go to Step 13. NO: Intermittent malfunction (Refer to «HOW TO USE TROUBLESHOOTING/HOW TO COPE WITH INTERMITTENT MALFUNCTIONS»(ref-592971-S42664974692014011300000) ).
13. STEP 13. Check whether the DTC is reset. Erase the DTC. Drive the vehicle at 12mph (20 km/h) or higher. Q: Is DTC C2114 or C2115 set? YES: Return to Step 1 . NO: The procedure is complete.

1. ASC-ECU malfunction
2. External noise interference
3. Improper installation of G and yaw rate sensor or steering wheel sensor

1. Improper installation of steering wheel sensor
2. Wheel alignment not performed
3. Steering wheel sensor malfunction
4. Different steering wheel
5. G and yaw rate sensor malfunction
6. Malfunction of wheel speed sensor
7. ASC-ECU malfunction
8. External noise interference

1. Steering wheel sensor malfunction
2. ASC-ECU malfunction
3. Neutral position of steering wheel sensor not learned

1. Steering wheel sensor malfunction
2. ASC-ECU malfunction
3. External noise interference

1. ASC-ECU malfunction
2. Noise interference

1. ETACS-ECU or ASC-ECU which was equipped with other vehicle is used.
2. Faulty installation of ETACS-ECU or ASC-ECU
3. Faulty ETACS-ECU coding
4. Malfunction of ETACS-ECU
5. ASC-ECU malfunction

1. Disconnection of the ASC-ECU connector or the battery terminal when the ignition switch is ON
2. Loose battery terminal
3. Abnormality in battery
4. Damaged wiring harness and connectors
5. ASC-ECU malfunction

Scheme 49

Scheme 50

1. STEP 1. Using scan tool MB991958, diagnose the CAN bus line. Use scan tool to diagnose the CAN bus lines. Q: Is the check result normal? YES: Go to Step 3 . NO: Repair the CAN bus lines (Refer to «CAN BUS DIAGNOSTICS TABLE»(ref-593004-S19873494462014011300000) ). On completion, and then go to Step 2.
2. STEP 2. Diagnostic trouble code recheck after resetting CAN bus lines Q: Is DTC C1608 set? YES: Go to Step 3. NO: The procedure is complete.
3. STEP 3. Battery check Refer to «BATTERY TEST»(ref-592987-S27291057822014011300000) . Q: Is the battery in good condition? YES: Go to Step 5 . NO: Go to Step 4.
4. STEP 4. Charging system check Refer to «ON-VEHICLE SERVICE/OUTPUT CURRENT TEST»(ref-593005-S11515354572014011300000) . Q: Is the charging system in good condition? YES: Replace the battery. Then go to Step 11 . NO: Repair or replace the charging system component(s).
5. STEP 5. Voltage measurement at the A-03 ASC-ECU connector Disconnect the connector, connect special tool MB991997 to the harness-side connector, and measure the voltage at the special tool connector side. NOTE: Do not connect the special tool MB991997 to ASC-ECU. Measure the voltage between the terminal No. 2 and the body ground. OK: Approximately system voltage Q: Is the check result normal? YES: Go to Step 7 . NO: Go to Step 6.
6. STEP 6. Connector check: A-03 ASC-ECU connector Q: Is the check result normal? YES: The open or short circuit may be present in the power supply circuit. Repair the wiring harness between the A-03 ASC-ECU connector terminal No. 02 and fuse No. 17. NO: Repair the defective connector.
7. STEP 7. Resistance measurement at A-03 ASC-ECU connector Disconnect the ASC-ECU connector, connect special tool ASC check harness (MB991997) to the harness-side connector, and then measure the resistance at the special tool connector side. NOTE: Do not connect the special tool ASC check harness (MB991997) to ASC-ECU. Resistance between the terminal No. 16 and the body ground, and between the terminal No. 47 and the body ground OK: Continuity exists (2 ohms or less) Q: Is the check result normal? YES: Go to Step 9 . NO: Go to Step 8.
8. STEP 8. Connector check: A-03 ASC-ECU connector Q: Is the check result normal? YES: An open circuit may be present in the ground circuit. Repair the wiring harness between the A-03 ASC-ECU terminal No. 16 and body ground, and between the A-03 ASC-ECU terminal No. 47 and body ground. NO: Repair the defective connector.
9. STEP 9. Check whether the DTC is reset. Erase the DTC. Turn the ignition switch to the "LOCK" (OFF) position. Turn the ignition switch to the "ON" position. Drive the vehicle at 12mph (20 km/h) or higher. NOTE: The ABS warning light does not turn OFF in some cases unless the vehicle runs at 12mph (20 km/h) or higher. Q: Is DTC C1608 set? YES: Replace the hydraulic unit (integrated with ASC-ECU) (Refer to «HYDRAULIC UNIT»(ref-592981-S29861285002014011300000) ). Then go to Step 10. NO: Go to Step 11 .
10. STEP 10. Check whether the DTC is reset. Erase the DTC. Turn the ignition switch to the "LOCK" (OFF) position. Turn the ignition switch to the "ON" position. Drive the vehicle at 12mph (20 km/h) or higher. NOTE: The ABS warning light does not turn OFF in some cases unless the vehicle runs at 12mph (20 km/h) or higher. Q: Is DTC C1608 set? YES: Return to Step 1 . NO: Go to Step 11.
11. STEP 11. Check the other DTCs. Erase the DTC. Turn the ignition switch to the "LOCK" (OFF) position. Turn the ignition switch to the "ON" position. Drive the vehicle at 12mph (20 km/h) or higher. NOTE: The ABS warning light does not turn OFF in some cases unless the vehicle runs at 12mph (20 km/h) or higher. Q: Is any DTC set? YES: Carry out the applicable troubleshooting for the DTC (Refer to «DIAGNOSTIC TROUBLE CODE CHART»(ref-592981-S31275134652014011300000) ). NO: The procedure is complete.

1. Wiring harness or connector failure of CAN bus line
2. ASC-ECU malfunction
3. Other ECU malfunction

1. Wiring harness or connector failure in special CAN bus lines between ASC-ECU and G and yaw rate sensor
2. G and yaw rate sensor malfunction
3. ASC-ECU malfunction
4. External noise interference
5. Connector disconnected or improperly connected
6. Stretched or broken wires

1. Malfunction of engine system
2. Engine control module malfunction
3. ASC-ECU malfunction
4. External noise interference

1. Steering wheel sensor malfunction
2. ASC-ECU malfunction
3. External noise interference

1. Wiring harness or connector failure for the special CAN bus lines between ASC-ECU and the G and yaw rate sensor
2. G and yaw rate sensor malfunction
3. ASC-ECU malfunction
4. Connector disconnected or improperly connected
5. Stretched or broken wires

1. Variant coding for ETACS-ECU has not been implemented.
2. ASC-ECU malfunction

1. ETACS-ECU malfunction
2. Engine control module malfunction
3. ETACS-ECUs have been interchanged between two vehicles.
4. ASC-ECU malfunction
5. External noise interference
6. ASC-ECUs have been interchanged between two vehicles.

1. Damaged wiring harness and connectors
2. ASC-ECU malfunction
3. Wrong routing of scan tool harness
4. Abnormality in battery or generator
5. Abnormality in power supply voltage to ASC-ECU
6. ECU malfunction of other system

1. Overheat of brake pad

Scheme 51

1. The brake pad thickness is at the limit value or less.
2. The brake fluid amount is at the "LOWER" level or lower.
3. Poor adjustment of the parking brake lever
4. Damaged wiring harness and connectors
5. Parking brake switch malfunction
6. Brake fluid level switch malfunction
7. Combination meter malfunction
8. ETACS-ECU malfunction

1. Damaged wiring harness and connectors
2. Malfunction of ETACS-ECU
3. Combination meter malfunction
4. ASC-ECU malfunction
5. The ETACS-ECU coding data is abnormal.

1. Damaged wiring harness and connectors
2. Malfunction of ETACS-ECU
3. Malfunction of the combination meter
4. ASC-ECU malfunction

1. Damaged wiring harness and connectors
2. ETACS-ECU malfunction
3. Combination meter malfunction
4. ASC-ECU malfunction
5. Control stop due to the low voltage NOTE: Due to the abnormality in the supply voltage, the diagnostic trouble code may not be set even when the ABS warning light is illuminated.

1. Damaged wiring harness and connectors
2. Malfunction of ETACS-ECU
3. Combination meter malfunction
4. ASC-ECU malfunction
5. Control is disabled due to the low voltage NOTE: Due to the abnormality in the supply voltage, the diagnostic trouble code may not be set even when the ASC warning display illuminates.

1. Damaged wiring harness and connectors
2. ETACS-ECU malfunction
3. Combination meter malfunction
4. ASC-ECU malfunction
5. ASC OFF switch malfunction

1. Damaged wiring harness and connectors
2. ETACS-ECU malfunction
3. Combination meter malfunction
4. ASC-ECU malfunction

1. Damaged wiring harness and connectors
2. ASC OFF switch malfunction
3. ETACS-ECU malfunction
4. The ASC OFF switch is pressed for more than 15 seconds (The system returns to normal by pressing the ignition switch to the "OFF" position and to the "ON" position).

1. Hydraulic unit (Integrated with ASC-ECU) malfunction
2. Malfunction of hydraulic circuit
3. Malfunction of brake assembly
4. Malfunction of brake booster
5. Malfunction of master cylinder assembly

1. Low battery output
2. Wiring harness or connector failure of CAN bus line
3. ASC-ECU malfunction
4. Different ETACS-ECU, abnormal variant coding information

1. Damaged wiring harness and connectors
2. Malfunction of fuse or fusible link
3. Improper tightening of battery terminal
4. Improper tightening of grounding bolt
5. Battery failure
6. Charging system failed
7. ASC-ECU malfunction

Scheme 52

Scheme 53

Scheme 54

Scheme 55

Scheme 56

Scheme 57

Scheme 58

Scheme 59

1. STEP 1. Battery check Refer to «BATTERY TEST»(ref-592987-S27291057822014011300000) . Q: Is the battery in good condition? YES: Go to Step 3 . NO: Charge or replace the battery. Then go to Step 2.
2. STEP 2. Charging system check Refer to «ON-VEHICLE SERVICE/OUTPUT CURRENT TEST»(ref-593005-S11515354572014011300000) . Q: Is the charging system in good condition? YES: Go to Step 3. NO: Repair or replace the charging system component(s).
3. STEP 3. Connector check: A-03 ASC-ECU connector, C-127 intermediate connector, C-417 ETACS-ECU connector, C-415 ETACS-ECU connector Q: Is the check result normal? YES: Go to Step 4. NO: Repair the damaged connector.
4. STEP 4. Voltage measurement at the A-03 ASC-ECU connector Disconnect the ASC-ECU connector, connect special tool ASC check harness (MB991997) to the harness-side connector, and then measure the voltage at the special tool connector side. NOTE: Do not connect the special tool ASC check harness (MB991997) to ASC-ECU. Measure the voltage between terminal No. 32 and body ground. OK: Approximately system voltage Q: Is the check result normal? YES: Go to Step 7 . NO: Go to Step 5.
5. STEP 5. Fusible link check: Check the fusible link No. 27. Q: Is the check result normal? YES: The open circuit may be present in the power supply circuit. Repair the wiring harness between the A-03 ASC-ECU connector terminal No. 32 and the fusible link No. 27. Then go to Step 20 . NO: Go to Step 6.
6. STEP 6. Resistance measurement at A-03 ASC-ECU connector Removal the fusible link No. 27. Disconnect the ASC-ECU connector, connect special tool ASC check harness (MB991997) to the harness-side connector, and then measure the resistance at the special tool connector side. NOTE: Do not connect the special tool ASC check harness (MB991997) to ASC-ECU. Measure the resistance between the terminal No. 32 and the body ground. OK: No continuity Q: Is the check result normal? YES: Replace the fusible link No. 27. Then go to Step 20 . NO: The short circuit may be present in the power supply circuit. Repair the wiring harness between the A-03 ASC-ECU connector terminal No. 32 and the fusible link No. 27, and then replace the fusible link No. 27. Then go to Step 20 .
7. STEP 7. Voltage measurement at the A-03 ASC-ECU connector Disconnect the ASC-ECU connector, connect special tool ASC check harness (MB991997) to the harness-side connector, and then measure the voltage at the special tool connector side. NOTE: Do not connect the special tool ASC check harness (MB991997) to ASC-ECU. Measure the voltage between terminal No. 1 and body ground. OK: Approximately system voltage Q: Is the check result normal? YES: Go to Step 10 . NO: Go to Step 8.
8. STEP 8. Check the fusible link No. 26. Q: Is the check result normal? YES: The open circuit may be present in the power supply circuit. Repair the wiring harness between the A-03 ASC-ECU connector terminal No. 1 and the fusible link No. 26. Then go to Step 20 . NO: Go to Step 9.
9. STEP 9. Resistance measurement at A-03 ASC-ECU connector Removal the fusible link No. 26. Disconnect the ASC-ECU connector, connect special tool ASC check harness (MB991997) to the harness-side connector, and then measure the resistance at the special tool connector side. NOTE: Do not connect the special tool ASC check harness (MB991997) to ASC-ECU. Measure the resistance between the terminal No. 1 and the body ground. OK: No continuity Q: Is the check result normal? YES: Replace the fusible link No. 26. Then go to Step 20 . NO: The short circuit may be present in the power supply circuit. Repair the wiring harness between the A-03 ASC-ECU connector terminal No. 1 and the fusible link No. 26, and then replace the fusible link No. 26. Then go to Step 20 .
10. STEP 10. Voltage measurement at the A-03 ASC-ECU connector Disconnect the ASC-ECU connector, connect special tool ASC check harness (MB991997) to the harness-side connector, and then measure the voltage at the special tool connector side. NOTE: Do not connect the special tool ASC check harness (MB991997) to ASC-ECU. Ignition switch: "ON" position. Measure the voltage between terminal No. 8 and body ground. OK: Approximately system voltage Q: Is the check result normal? YES: Go to Step 14 . NO: Go to Step 11.
11. STEP 11. Check the fuse No. 12. Visually check for open circuit in fuse No. 12. Q: Is the check result normal? YES: Go to Step 12. NO: Go to Step 13 .
12. STEP 12. Resistance measurement at A-03 ASC-ECU connector Disconnect the C-417 ETACS-ECU connector. Disconnect the A-03 ASC-ECU connector, connect special tool ASC check harness (MB991997) to the harness-side connector, and then measure the resistance at the special tool connector side. NOTE: Do not connect the special tool ASC check harness (MB991997) to ASC-ECU. Measure the resistance between the A-03 ASC-ECU connector terminal No. 8 and the C-417 ETACS-ECU connector terminal No. 5. OK: Continuity exists (2 ohms or less) Q: Is the check result normal? YES: The trouble can be an intermittent malfunction (Refer to «HOW TO USE TROUBLESHOOTING/HOW TO COPE WITH INTERMITTENT MALFUNCTIONS»(ref-592971-S42664974692014011300000) ). NO: The open circuit may be present in the power supply circuit. Repair the wiring harness between the A-03 ASC-ECU connector terminal No. 8 and the C-417 ETACS-ECU connector terminal No. 5. Then go to Step 20 .
13. STEP 13. Resistance measurement at A-03 ASC-ECU connector Disconnect the C-417 ETACS-ECU connector. Disconnect the ASC-ECU connector, connect special tool ASC check harness (MB991997) to the harness-side connector, and then measure the resistance at the special tool connector side. NOTE: Do not connect the special tool ASC check harness (MB991997) to ASC-ECU. Measure the resistance between the terminal No. 8 and the body ground. OK: No continuity Q: Is the check result normal? YES: Replace the fuse No. 12. Then go to Step 20 . NO: The short circuit may be present in the power supply circuit. Repair the wiring harness between the A-03 ASC-ECU connector terminal No. 8 and the C-417 ETACS-ECU connector terminal No. 5, and then replace the fuse No. 12. Then go to Step 20 .
14. STEP 14. Voltage measurement at the A-03 ASC-ECU connector Disconnect the ASC-ECU connector, connect special tool ASC check harness (MB991997) to the harness-side connector, and then measure the voltage at the special tool connector side. NOTE: Do not connect the special tool ASC check harness (MB991997) to ASC-ECU. Measure the voltage between terminal No. 2 and body ground. OK: Approximately system voltage Q: Is the check result normal? YES: Go to Step 18 . NO: Go to Step 15.
15. STEP 15. Check the fuse No. 17. Visually check for open circuit in fuse No. 17. Q: Is the check result normal? YES: Go to Step 16. NO: Go to Step 17 .
16. STEP 16. Resistance measurement at A-03 ASC-ECU connector Disconnect the C-415 ETACS-ECU connector. Disconnect the A-03 ASC-ECU connector, connect special tool ASC check harness (MB991997) to the harness-side connector, and then measure the resistance at the special tool connector side. NOTE: Do not connect the special tool ASC check harness (MB991997) to ASC-ECU. Measure the resistance between the A-03 ASC-ECU connector terminal No. 2 and the C-415 ETACS-ECU connector terminal No. 4. OK: Continuity exists (2 ohms or less) Q: Is the check result normal? YES: The trouble can be an intermittent malfunction (Refer to «HOW TO USE TROUBLESHOOTING/HOW TO COPE WITH INTERMITTENT MALFUNCTIONS»(ref-592971-S42664974692014011300000) ). NO: The open circuit may be present in the power supply circuit. Repair the wiring harness between the A-03 ASC-ECU connector terminal No. 2 and the C-415 ETACS-ECU connector terminal No. 4. Then go to Step 20 .
17. STEP 17. Resistance measurement at A-03 ASC-ECU connector Disconnect the C-415 ETACS-ECU connector. Disconnect the ASC-ECU connector, connect special tool ASC check harness (MB991997) to the harness-side connector, and then measure the resistance at the special tool connector side. NOTE: Do not connect the special tool ASC check harness (MB991997) to ASC-ECU. Measure the resistance between the terminal No. 2 and the body ground. OK: No continuity Q: Is the check result normal? YES: Replace the fuse No. 17. Then go to Step 20 . NO: The short circuit may be present in the power supply circuit. Repair the wiring harness between the A-03 ASC-ECU connector terminal No. 2 and the C-415 ETACS-ECU connector terminal No. 4, and then replace the fuse No. 17. Then go to Step 20 .
18. STEP 18. Resistance measurement at the A-03 ASC-ECU connector Disconnect the ASC-ECU connector, connect special tool ASC check harness (MB991997) to the harness-side connector, and then measure the resistance at the special tool connector side. NOTE: Do not connect the special tool ASC check harness (MB991997) to ASC-ECU. Measure the resistance between terminal No. 16 and body ground, and between terminal No. 47 and body ground. OK: Continuity exists (2 ohms or less) Q: Is the check result normal? YES: Go to Step 19. NO: An open circuit may be present in the ground circuit. Repair the wiring harness between the A-03 ASC-ECU connector terminal No. 16 and the body ground, and between the A-03 ASC-ECU connector terminal No. 47 and the body ground.
19. STEP 19. Retest the system. Make sure that the scan tool cable is properly connected and the V.C.I. switch is "ON". Q: Is the communication with scan tool possible? YES: Intermittent malfunction (Refer to «HOW TO USE TROUBLESHOOTING/HOW TO COPE WITH INTERMITTENT MALFUNCTIONS»(ref-592971-S42664974692014011300000) ). NO: Replace the hydraulic unit (integrated with ASC-ECU) (Refer to «HYDRAULIC UNIT»(ref-592981-S29861285002014011300000) ). Then go to Step 20.
20. STEP 20. Retest the system. Q: Is the communication with scan tool possible? YES: Return to Step 1 . NO: The procedure is complete.

Scheme 60

1. Damaged wiring harness and connectors
2. Fuse and fusible link malfunction
3. Improper tightening of battery terminal
4. Battery failure
5. Charging system failed
6. Steering wheel sensor malfunction

1. Improper installation of the G and yaw rate sensor
2. G and yaw rate sensor malfunction
3. Calibration failure of the G and yaw rate sensor
4. Calibration failure of the brake fluid pressure sensor
5. Seizure of the parking brake switch
6. Malfunction of wheel speed sensor
7. Malfunction of transmission range switch
8. Malfunction of ETACS-ECU
9. Malfunction of hydraulic unit (integrated with ASC-ECU)
10. Wiring harness or connector failure of CAN bus line
11. Damaged wiring harness and connectors

1. Improper installation of the G and yaw rate sensor
2. G and yaw rate sensor malfunction
3. Brake drag
4. Damaged wiring harness and connectors

1. Improper installation of the hydraulic unit
2. Improper installation of the brake tube

DATA LIST REFERENCE TABLE

The following items of ECU input data can be read using scan tool.

DATA LIST REFERENCE

TERMINAL VOLTAGE CHECK

Required Special Tool

MB991997: ASC Check Harness

Connect the special tool ASC check harness (MB991997) to measure the voltage between each check connector terminal and the ground terminal (No. 16 or 47).

Scheme 61

NORMAL CONDITION

WHEEL SPEED SENSOR OUTPUT CURRENT MEASUREMENT

Required Special Tools

1. MB991709: Wiring harness set

The relevant wheel, on which the wheel speed sensor is fitted, should be free to run.

Scheme 62

1. Remove the wheel speed sensor connector to be checked. CAUTION: For precise measurement, do not connect to the wheel speed sensor-side connector and the wiring harness side connector terminal No. 1.
2. Use the special tool test harness (MB991709) to connect a multimeter between the wheel speed sensor-side connector and the wiring harness connector terminal No. 2.
3. Turn the ignition switch to the "ON" position. CAUTION: Do not rotate the wheel too quickly. Output current changes significantly as the wheel speed detection magnetic encoder comes near or goes away from the wheel speed sensor.
4. Rotate the wheel, on which the wheel speed sensor is fitted, quite slowly to measure the output current with the multimeter. Standard value: 5.9 to 8.4 mA or 11.8 to 16.8 mA
5. If the measurement is not within the standard value, or the output current does not change in proportion to the wheel rotation, replace the wheel speed sensor (Refer to «WHEEL SPEED SENSOR»(ref-592981-S10617845292014011300000) ).

HYDRAULIC UNIT CHECK

Required Special Tools

1. MB991958: scan tool Sub Assembly MB991824: Vehicle Communication Interface (V.C.I.) MB991827: scan tool USB Cable MB991910: scan tool Main Harness A (Vehicles with CAN communication system)

Scheme 63

1. Raise the vehicle using a jack and support the specified points with a rigid rack. CAUTION: Before connecting or disconnecting scan tool, always turn the ignition switch to the LOCK (OFF) position.
2. Before setting scan tool, turn the ignition key to the LOCK (OFF) position.
3. Confirm that the selector lever is in the "N" position, and then start the engine.
4. When carrying out the actuator tests No. 01 to 04, perform the actuator tests using scan tool while depressing the brake pedal. When carrying out the actuator tests No. 05 to 08, perform the actuator tests using scan tool without depressing the brake pedal. When carrying out the actuator tests, rotate the wheel by hands to confirm that the braking force changes. NOTE: While performing the actuator test, the ABS warning light flashes at a rate of 2 Hz. When ASC-ECU is disabled due to the fail-safe function, the scan tool actuator test cannot be performed. After the actuator test has been performed, the ABS warning light, brake waning light, ASC ON indicator light, and ASC OFF indicator light illuminate until the ignition switch is turned to ON again or the communication between scan tool and ASC-ECU is terminated.
5. This is indicated as shown in the above illustration.
6. When any malfunction has been found, take a necessary action according to the "Judgment Chart." Judgment Chart JUDGMENT CHART Display on scan tool Operation Test result Judgment Cause Measure 01 FL wheel ABS 02 FR wheel ABS 03 RL wheel ABS 04 RR wheel ABS Depress the brake pedal to lock the wheel. Select the vehicle to be inspected using scan tool, perform the actuator test. Rotate the selected wheel by hands to confirm the braking force. Braking force decreases for 3 seconds from the lock status. Normal - - The wheel does not lock even if the brake pedal is depressed. Error Clogged brake line other than hydraulic unit Check and clean the brake line. Clogged hydraulic circuit in the hydraulic unit Replace the hydraulic unit assembly. Braking force does not decrease. Faulty routing of hydraulic unit brake tube Route the brake tube correctly. Malfunction of hydraulic unit solenoid valve operation Replace the hydraulic unit assembly. 05 FL wheel TCL 06 FR wheel TCL 07 RL wheel TCL 08 RR wheel TCL Select the vehicle to be inspected using scan tool, perform the actuator test. Rotate the selected wheel by hands to confirm the braking force. Lock condition occurs for 3 seconds from the status without braking force. Normal - - The wheel does not lock. Error Faulty routing of hydraulic unit brake tube Clogged brake line other than hydraulic unit Check and clean the brake line. Clogged hydraulic circuit in the hydraulic unit Replace the hydraulic unit assembly.
7. After the inspection, turn the ignition switch to the LOCK (OFF) position, and then disconnect scan tool.

IN THE EVENT OF A DISCHARGED BATTERY

If the engine is started using a booster cable when the battery is completely flat, and the vehicle is then driven without waiting for the battery to be recharged, the engine may misfire and it may not be possible to drive the vehicle. This is because the ASC consumes a large amount of current when carrying out its initial checks. If this happens, recharge the battery fully.

>> A << BRAKE TUBE CONNECTION

Install the brake pipe to the hydraulic unit as shown in the illustration.

Scheme 64

1. From master cylinder (primary) < Marking color: Blue >
2. To front brake (RH) < Marking color: Orange >
3. To front brake (LH) < Marking color: Red >
4. From master cylinder (secondary) < Marking color: Yellow >
5. To rear brake (LH) < Marking color: Pink >
6. To rear brake (RH) < Marking color: White >

WHEEL SPEED SENSOR CURRENT CHECK

Scheme 65

1. Connect the circuit tester to the wheel speed sensor using the special tool extra fine probe (MB992006), and measure the sensor current as a single unit. Standard value: 5.9 to 8.4 mA or 11.8 to 16.8 mA
2. If the measurement value is not within the standard value range, replace the wheel speed sensor with a new one.

Scheme 66

1. Connect the circuit tester to the wheel speed sensor using the special tool extra fine probe (MB992006), and measure the insulation resistance between terminal No. 1/2 and the wheel speed sensor body as a single unit. Standard value: 5 Mohms or more
2. If the insulation resistance is not within the standard value range, replace the wheel speed sensor with a new one.

Scheme 67

Scheme 68

Required Special Tools

1. MB991958: Scan Tool (M.U.T.-III Sub Assembly) MB991824: Vehicle Communication Interface (V.C.I.) MB991827: M.U.T.-III USB Cable MB991910: M.U.T.-III Main Harness A