Code No. C2104 Valve power supply circuit


caution If there is any problem in the CAN bus lines, an incorrect diagnosis code may be set. Prior to this diagnosis, diagnose the CAN bus lines (Refer to GROUP 54C - CAN Bus Diagnostics Table ).

OPERATION

  • ABS-ECU contains the power supply circuit (+BV terminal) for the solenoid valve. The solenoid valve is energised by the valve relay, which is incorporated in ABS-ECU.
  • The valve relay, which is incorporated in ABS-ECU, is always energising the solenoid valve unless the initial check is in progress when the ignition switch is turned on, and the recurrent system check is in progress.

DIAGNOSIS CODE SET CONDITIONS
This diagnosis code will be set when the solenoid valve supply voltage is not within the standard value.

PROBABLE CAUSES
Current trouble
  • Fusible link malfunction
  • Damaged wiring harness and connectors
  • Abnormality in battery or alternator
  • ABS-ECU malfunction
Past trouble
  • Carry out diagnosis with particular emphasis on wiring harness and connector failures between the power supply circuit (+BV terminal) to ABS-ECU solenoid valve or earth circuit (GND1, GND2 terminal). For diagnosis procedures, refer to How to treat past trouble (GROUP 00 - How to Use Troubleshooting/How to Treat Past Trouble ).

DIAGNOSTIC PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use M.U.T.-III to diagnose the CAN bus lines.

Q. Is the check result normal?
Go to Step 3.
Repair the CAN bus lines (Refer to GROUP 54C - CAN Bus Diagnostics Table ). On completion, go to Step 2.

STEP 2. Diagnosis code recheck after resetting CAN bus lines

Q. Is the diagnosis code No.C2104 set?
Go to Step 3.
This diagnosis is complete.

STEP 3. Battery check
Refer to GROUP 54A - Battery Test .

Q. Is the battery in good condition?
Go to Step 4.
Replace the battery. Then go to Step 10.

STEP 4. Charging system check
Refer to GROUP 16 - On-vehicle Service/Alternator Output Line Voltage Drop Test .

Q. Is the charging system in good condition?
Go to Step 5.
Repair or replace the charging system component(s). Then go to Step 10.

STEP 5. Fusible link check: Check the fusible link No.4 and SBF7.
Visually check for open circuit in the fusible link No.4 and SBF7.

Q. Is the check result normal?
Go to Step 7.
Go to Step 6.

STEP 6. Resistance measurement at ABS-ECU connector
(1)Disconnect the connector, and measure at the wiring harness side.
(2)Disconnect the fusible link No.SBF7.
(3)Resistance between the +BV terminal and the body earth.
OK: No continuity

Q. Is the check result normal?
Replace the fusible link No.4 or SBF7. Then go to Step 10.
The short circuit may be present in the power supply circuit. Repair the wiring harness between the ABS-ECU connector +BV terminal and the fusible link, and then replace the fusible link No.4 or SBF7. Then go to Step 10.

STEP 7. Voltage measurement at the ABS-ECU connector
(1)Disconnect the connector, and measure at the wiring harness side.
(2)Measure the voltage between the +BV terminal and the body earth.
OK: Approximately system voltage

Q. Is the check result normal?
Go to Step 8.
The open circuit may be present in the power supply circuit. Repair the wiring harness between the ABS-ECU connector +BV terminal and the fusible link. Then go to Step 10.

STEP 8. Resistance measurement at ABS-ECU connector
(1)Disconnect the connector, and measure at the wiring harness side.
(2)Resistance between the GND1 terminal and the body earth, and between the GND2 terminal and the body earth
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?
Go to Step 9.
An open circuit may be present in the earth circuit. Repair the wiring harness between the ABS-ECU connector GND1 terminal and the body earth, and between the ASC-ECU connector GND2 terminal and the body earth. Then go to Step 10.

STEP 9. Check whether the diagnosis code is reset.
Erase the diagnosis code.

Q. Is the diagnosis code No.C2104 set?
Replace the hydraulic unit (integrated with ABS-ECU) (Refer to ). Then go to Step 10.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/ How to Cope with Intermittent Malfunctions ).

STEP 10. Check whether the diagnosis code is reset.
Erase the diagnosis code.

Q. Is the diagnosis code No.C2104 set?
Return to Step 1.
This diagnosis is complete.