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Home >> Mitsubishi >> 2010 >> Eclipse L4-2.4L (4G69) >> Repair and Diagnosis >> A L L Diagnostic Trouble Codes ( DTC ) >> Testing and Inspection >> C Code Charts >> C1251

C1251

DTC C1226: FR inlet valve

DTC C1231: FR outlet valve

DTC C1236: FL inlet valve

DTC C1241: FL outlet valve

DTC C1246: RR inlet valve

DTC C1251: RR outlet valve

DTC C1256: RL inlet valve

DTC C1261: RL outlet valve

DTC C1300: FR cut valve

DTC C1305: FR suction valve

DTC C1310: FL cut valve

DTC C1315: FL suction valve








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 TCL/ASC-ECU contains the power supply circuit (terminal 32) for the solenoid valve. The solenoid valve is energized by the valve relay, which is incorporated in the TCL/ASC-ECU.
^ The valve relay, which is incorporated in the TCL/ASC-ECU, is always energizing the solenoid valve unless the initial check is in progress when the ignition switch is turned on.
^ The TCL/ASC-ECU activates the solenoid valve by turning on its driving transistor.

DTC SET CONDITIONS
These diagnostic trouble codes will be set under the cases below.
^ The solenoid valve is not energized even after the TCL/ASC-ECU has turned on the driving transistor (Open circuit is present in the power supply circuit to the TCL/ASC-ECU solenoid valve, or the valve relay has failed).
^ The solenoid valve is not energized even after the TCL/ASC-ECU has turned on the driving transistor (Open circuit is present in the solenoid valve circuit inside the TCL/ASC-ECU, or the valve relay has failed).
^ After the TCL/ASC-ECU has turned off the driving transistor, the solenoid valve still remains energized (short in the solenoid valve circuit).
^ When a solenoid valve failure is detected

TROUBLESHOOTING HINTS (The most likely causes for these DTCs are to set are:)

Current trouble
^ Malfunction of the hydraulic unit (integrated with TCL/ASC-ECU)

Past trouble
^ Carry out diagnosis with particular emphasis on connector(s) or wiring harness in the power supply circuit (terminal 32) to the TCL/ASC-ECU solenoid valve or ground circuit (terminal 16, 47).

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 (Refer to Diagnosis How to Diagnose the CAN Bus Line). 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) Erase the DTC.
2) Turn the ignition switch to the "ON" position.
3) Check if the DTC is set.
4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC C1226, C1231, C1236, C1241, C1246, C1251, C1256, C1261, C1300, C1305, C1310 or C1315 set?
YES: Go to Step 3.
NO: The procedure is complete.

STEP 3. 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 C1226, C1231, C1236, C1241, C1246, C1251, C1256, C1261, C1300, C1305, C1310 or C1315 set?
YES: Replace the hydraulic unit (integrated with TCL/ASC-ECU). Then go to Step 4.
NO: It can be assumed that this malfunction is intermittent.

STEP 4. 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 C1226, C1231, C1236, C1241, C1246, C1251, C1256, C1261, C1300, C1305, C1310 or C1315 set?
YES: Go to Step 1.
NO: The procedure is complete.

DTC C1271: Motor drive circuit





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.

CAUTION
Whenever the ECU is replaced, ensure that the CAN bus lines are normal.

CAUTION
When I replace hydraulic unit (integrated with TCL/ASC-ECU), Always perform the calibration of steering wheel sensor and yaw rate sensor.

CIRCUIT OPERATION
^ The TCL/ASC-ECU contains the power supply circuit (terminal 1) for the pump motor. The pump motor is energized by the motor relay, which is incorporated in the TCL/ASC-ECU.
^ The motor relay, which is incorporated in the TCL/ASC-ECU, is always off unless the motor solenoid valve check is activated when the vehicle is started.
^ The TCL/ASC-ECU activates the pump motor by turning on the ECU built-in motor relay when the TCL/ASC system is working.

TCL/ASC DTC SET CONDITIONS
^ When pump motor drive time or a voltage descent of a pump motor switch after drive showed a high value, The TCL/ASC-ECU stop pump motor drive, and this DTC is output.

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

Current trouble
^ Defective battery
^ Charging system failed
^ 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 in the power supply circuit (terminal 1) to the TCL/ASC-ECU motor or ground circuit (terminal 16, 47).

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 (Refer to Diagnosis How to Diagnose the CAN Bus Line). 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 C1271 set ?
YES: Go to Step 3.
NO: The procedure is complete.

STEP 3. Battery check
Refer to Battery Test Battery Test.
Q: Is the battery in good condition?
YES: Go to Step 5.
NO: Replace the battery. Then go to Step 4.

STEP 4. Charging system check
Refer to Charging System Initial Inspection and Diagnostic Overview.
Q: Is the charging system in good condition?
YES: Go to Step 5.
NO: Repair or replace the charging system component(s). Then go to Step 10.

STEP 5. Measure the voltage at 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) Turn the ignition switch to the "ON" position.
3) Measure the voltage between terminal 1 and ground. It should be approximately 12 volts (battery positive voltage).
Q: Is the voltage approximately 12 volts (battery positive voltage)?
YES: Go to Step 7.
NO: Go to Step 6.

STEP 6. Check TCL/ASC-ECU connector A-38 for loose, corroded or damaged terminals, or terminals pushed back in the connector.





Q: Is TCL/ASC-ECU connector A-38 damaged?
YES: Repair or replace the damaged component(s). Then go to Step 10.
NO: An open or short circuit may be present in the solenoid valve power supply circuit. Repair the wiring harness between TCL/ASC-ECU connector A-38 terminal 1 and fusible link No.3. Then go to Step 10.

STEP 7. Measure the resistance at 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 16, 47 and ground. It should be 2 ohms or less.
Q: Is the measured resistance 2 ohms or less?
YES: Go to Step 9.
NO: Go to Step 8.

STEP 8. Check TCL/ASC-ECU connector A-38 for loose, corroded or damaged terminals, or terminals pushed back in the connector.





Q: Is TCL/ASC-ECU connector A-38 damaged?
YES: Repair or replace the damaged component(s). Then go to Step 10.
NO: An open circuit may be present in the ground circuit. Repair the wiring harness between TCL/ASC-ECU connector A-38 terminal 16, 47 and the body ground. Then go to Step 10 .

STEP 9. 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 C1271 set ?
YES: Replace the hydraulic unit (integrated with TCL/ASC-ECU). Then go to Step 10.
NO: It can be assumed that this malfunction is intermittent.

STEP 10. 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 C1271 set ?
YES: Go to Step 1.
NO: The procedure is complete.
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