Operation CHARM: Car repair manuals for everyone.

B1158




DTC B1157 OSS EEPROM fail
DTC B1158 OSS ECU internal fail


DIAGNOSTIC FUNCTION

- When an EEPROM writing/reading error of OSS-ECU is detected, OSS-ECU sets the DTC B1157, and flashes the indicator of engine switch in orange.
- When an error is detected to the microcomputer in OSS-ECU, OSS-ECU sets the DTC B1158, and flashes the indicator of engine switch in orange.

DTC SET CONDITION

Check Conditions

- After OSS-ECU activation
Judgment Criterion

- When the following conditions are met:
1. EEPROM writing/reading error is detected.
2. ECU internal circuit error is detected.

TROUBLESHOOTING HINTS

- Malfunction of OSS-ECU

DIAGNOSIS

Check whether the DTC is reset.

Q. Is the DTC set?

YES Replace the OSS-ECU and register the VIN (Refer to Programming and Relearning).
NO Intermittent malfunction is suspected How to Cope With Intermittent Malfunctions).