C1371

DTC C1366: Lateral G SNSR. stuck/low gain
DTC C1371: Yaw rate SNSR. stuck/low gain
DTC C1377: Communication error G and yaw rate SNSR.
DTC C1864: G and yaw rate SNSR. power supply voltage

CAUTION:
If there is any problem in the CAN bus lines, an incorrect diagnostic trouble code may be set. Prior to this diagnosis, diagnose the CAN bus lines.

CIRCUIT OPERATION

- The G and yaw rate sensor is power-supplied from TCL/ASC-ECU, and communicates with TCL/ASC-ECU via the special CAN bus lines.

TCL/ASC DTC SET CONDITIONS

These codes are set at the following cases:
DTC C1366: Lateral G SNSR. stuck/low gain (seizure or abnormal output signal)

- Lateral acceleration value from the sensor is abnormal, or the value does not fluctuate during driving.
DTC C1371: Yaw rate SNSR. stuck/low gain (seizure, abnormal output signal or oscillation)

- Yaw rate value from the sensor is abnormal, or the value does not fluctuate during driving.
DTC C1377: Communication error G and yaw rate SNSR. (seizure or abnormal output signal)

- When communication error of the G and yaw rate sensor occurs
DTC C1864: G and yaw rate SNSR. power supply voltage (abnormal output or poor performance)

- When the G and yaw rate sensor power supply voltage is abnormal

TROUBLESHOOTING HINTS (THE MOST LIKELY CAUSES FOR THESE DTCS ARE TO SET ARE:)

Current trouble

- Malfunction of the G and yaw late sensor
- Damaged wiring harness or connector
- Malfunction of the hydraulic unit (integrated with TCL/ASC-ECU)

PAST TROUBLE

Carry out diagnosis with particular emphasis on connector(s) or wiring harness between the TCL/ASC-ECU and the G and yaw late sensor. For diagnosis procedures, refer to "How to cope with past trouble" How to Treat Past Trouble).

DIAGNOSIS

Required Special Tools:

- 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
- MB991997: ASC Check Harness

STEP 1. Using scan tool MB991958, diagnose the CAN bus line.

CAUTION:
To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.

(1)Connect scan tool MB991958 to the data link connector.
(2)Turn the ignition switch to the "ON" position.
(3)Diagnose the CAN bus line.
(4)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is the CAN bus line found to be normal?

YES Go to Step 3.

NO Repair the CAN bus line CAN Bus Diagnostics Chart). Then go to Step 2.

STEP 2. Recheck for diagnostic trouble code.

CAUTION:
To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.

(1)Turn the ignition switch to the "ON" position.
(2)Erase the DTC.
(3)Turn the ignition switch to the "LOCK" (OFF) position.
(4)Turn the ignition switch to the "ON" position.
(5)Check if the DTC is set.
(6)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is DTC C1366, C1371, C1377 or C1864 set?

YES Go to Step 3.

NO The procedure is complete.

STEP 3. Using scan tool MB991958, check data list item 8: Lateral G sensor and item 12: Yaw rate sensor.

CAUTION:
To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.

(1)Connect scan tool MB991958 to the data link connector.
(2)Turn the ignition switch to the "ON" position.
(3)Use scan tool MB991958 to read the following data list (Refer to Data List Reference Table).

- Item 8: Lateral G sensor
- Item 12: Yaw rate sensor

Q. Is the G and yaw rate sensor output normal?

YES Then go to Step 13.

NO Go to Step 4.

STEP 4. Check the following connectors.

- G and yaw rate sensor connector C-32
- TCL/ASC-ECU connector A-38
Check the connectors, for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q. Are the connectors and terminals in good condition?

YES Go to Step 5.

NO Repair or replace the damaged component(s). Harness Connector Inspection.

STEP 5. Measure the voltage at G and yaw rate sensor connector C-32.

(1)Disconnect the G and yaw rate sensor connector C-32, and measure at the harness side connector.
(2)Turn the ignition switch to the "ON" position.
(3)Measure the voltage between terminal 1 and body ground.

- Voltage should measure battery positive voltage (approximately 12 volts).

Q. Is battery positive voltage (approximately 12 volts) present?

YES Go to Step 8.

NO Go to Step 6.

STEP 6. Measure the voltage at the TCL-ASC-ECU connector A-38.

(1)Disconnect the connector A-38, and connect special tool MB991997 to the wiring harness-side connector and TCL/ASC-ECU side.
(2)Turn the ignition switch to the "ON" position.
(3)Measure the voltage between terminal 6 and body ground.

- Voltage should measure battery positive voltage (approximately 12 volts).

Q. Is battery positive voltage (approximately 12 volts) present?

YES Open circuit may be present in the G and yaw rate sensor power supply lines. Repair the wiring harness between TCL/ASC-ECU connector A-38 (terminal 6) and G and yaw rate sensor connector C-32 (terminal 1). Then go to Step 14.

NO Go to Step 7.

STEP 7. Measure the resistance at the TCL-ASC-ECU connector A-38.

(1)Disconnect the connector A-38, and connect special tool MB991997 to the wiring harness-side connector.
NOTE:
Do not connect special tool MB991997 to the TCL/ASC-ECU.

(2)Measure the resistance between terminal 6 and body ground.

- Resistance should measure no continuity.

Q. Is the measured resistance no continuity?

YES Replace the hydraulic unit (integrated with TCL/ASC-ECU). Then go to Step 14.

NO Short circuit may be present in the G and yaw rate sensor power supply lines. Repair the wiring harness between TCL/ASC-ECU connector A-38 (terminal 6) and G and yaw rate sensor connector C-32 (terminal 1). Then go to Step 14.

STEP 8. Check for continuity of the wiring harness between A-38 TCL/ASC-ECU connector and C-32 G and yaw rate sensor connector.

(1)Disconnect the TCL/ASC-ECU connector A-38, and connect special tool MB991997 to the wiring harness-side connector.
NOTE:
Do not connect special tool MB991997 to the TCL/ASC-ECU.

(2)Disconnect the G and yaw rate sensor connector C-32.
(3)Measure the resistance between A-38 TCL/ASC-ECU connector terminal 31 and C-32 G and yaw rate sensor connector terminal 5.

- Resistance should measure 2 ohms or less.

Q. Is the measured resistance 2 ohms or less?

YES Go to Step 9.

NO Open may be present in the G and yaw rate sensor ground lines. Repair the wiring harness. Then go to Step 14.

STEP 9. Check for continuity of the wiring harness between A-38 TCL/ASC-ECU connector and C-32 G and yaw rate sensor connector.

(1)Disconnect the TCL/ASC-ECU connector A-38, and connect special tool MB991997 to the wiring harness-side connector.
NOTE:
Do not connect special tool MB991997 to the TCL/ASC-ECU.

(2)Disconnect the G and yaw rate sensor connector C-32.
(3)Measure the resistance between TCL/ASC-ECU connector A-38 (terminal 25) and G and yaw rate sensor connector C-32 (terminal 3), and between TCL/ASC-ECU connector A-38 (terminal 29) and G and yaw rate sensor connector C-32 (terminal 2).

- Resistance should measure 2 ohms or less.

Q. Is the measured resistance 2 ohms or less?

YES Go to Step 10.

NO Open circuit may be present in the special CAN bus line of the G and yaw rate sensor. Repair the wiring harness. Then go to Step 14.

STEP 10. Measure the resistance at the TCL-ASC-ECU connector A-38.

(1)Disconnect the connector A-38, and connect special tool MB991997 to the wiring harness-side connector.
NOTE:
Do not connect special tool MB991997 to the TCL/ASC-ECU.

(2)Disconnect the G and yaw rate sensor connector C-32.
(3)Measure the resistance between TCL/ASC-ECU connector A-38 (terminal 25) and body ground, and between TCL/ASC-ECU connector A-38 (terminal 29) and body ground.

- Resistance should measure no continuity.

Q. Is the measured resistance no continuity?

YES Go to Step 11.

NO Short circuit may be present in the special CAN bus line of the G and yaw rate sensor. Repair the wiring harness. Then go to Step 14.

STEP 11. Measure the resistance at the TCL-ASC-ECU connector A-38.

(1)Disconnect the connector A-38, and connect special tool MB991997 to the wiring harness-side connector.
NOTE:
Do not connect special tool MB991997 to the TCL/ASC-ECU.

(2)Disconnect the G and yaw rate sensor connector C-32.
(3)Measure the resistance between TCL/ASC-ECU connector A-38 (terminal 25) and TCL/ASC-ECU connector A-38 (terminal 29).

- Resistance should measure no continuity.

Q. Is the measured resistance no continuity?

YES Go to Step 12.

NO Short circuit may be present in the special CAN bus line of the G and yaw rate sensor. Repair the wiring harness. Then go to Step 14.

STEP 12. Recheck for diagnostic trouble code.

CAUTION:
To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.

(1)Connect scan tool MB991958 to the data link connector.
(2)Turn the ignition switch to the "ON" position.
(3)Erase the DTC.
(4)Turn the ignition switch to the "LOCK" (OFF) position.
(5)Turn the ignition switch to the "ON" position.
(6)Check if the DTC is set.
(7)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is DTC C1366, C1371, C1377 or C1864 set?

YES Replace the G and yaw rate sensor (Refer to Service and Repair). Then go to Step 13.

NO It can be assumed that this malfunction is intermittent. How to Cope With Intermittent Malfunctions.

STEP 13. Recheck for diagnostic trouble code.

Check again if the DTC is set.
(1)Turn the ignition switch to the "ON" position.
(2)Erase the DTC.
(3)Turn the ignition switch to the "LOCK" (OFF) position.
(4)Turn the ignition switch to the "ON" position.
(5)Check if the DTC is set.
(6)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is DTC C1366, C1371, C1377 or C1864 set?

YES Replace the hydraulic unit (integrated with TCL/ASC-ECU). Then go to Step 14.

NO The procedure is complete.

STEP 14. Recheck for diagnostic trouble code.