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 ).
Whenever ECU is replaced, ensure that the CAN bus lines are normal.
OPERATION
ABS-ECU stores the calibrated value of the G sensor.
DIAGNOSIS CODE SET CONDITIONS
This diagnosis code is set when the calibrated value for G sensor stored in ABS-ECU is
not within the predetermined range.
PROBABLE CAUSES
Power supply is shut down while the calibrated value is being stored.
ABS-ECU malfunction
DIAGNOSIS 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 diagnosis code No.C123A or C2002 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 5.
Go to Step 4.
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?
Replace the battery. Then go to Step 9.
Repair or replace the charging system component(s).
STEP 5. 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 7.
Go to Step 6.
STEP 6. Check of short to power supply, short to earth, and open circuit
in +BV line between fusible link and ABS-ECU connector
Q.
Is the check result normal?
Go to Step 7.
NO : Repair the fusible link, connector(s) or wiring harness.
STEP 7. 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.
Go to Step 8.
STEP 8. Check of open circuit in GND1, GND2 line between ABS-ECU connector
and body earth
Q.
Is the check result normal?
Go to Step 9.
NO : Repair the connector(s) or wiring harness.
STEP 9. Check whether the diagnosis code is reset.
Erase the diagnosis code.
Q.
Is diagnosis code No.C123A or C2002 set?
Replace the hydraulic unit (integrated with ABS-ECU) (Refer to ),
and 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.