Code No. B1157 OSS EEPROM fail
Code No. B1158 OSS ECU internal fail


DIAGNOSTIC FUNCTION



  • When an EEPROM writing/reading error of OSS-ECU is detected, OSS-ECU sets the diagnosis code No.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 diagnosis code No.B1158, and flashes the indicator of engine switch in orange.

JUDGEMENT CRITERIA


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.

PROBABLE CAUSES



  • Malfunction of OSS-ECU

DIAGNOSIS PROCEDURE

Check whether the diagnosis code is reset.

Q. Is the diagnosis code set?
Replace the OSS-ECU and register the chassis number (Refer to ).
Intermittent malfunction is suspected (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).