Code No. P1243: Inquiry/Response Error
FUNCTION
Monitors the computation function of the engine-ECU.
TROUBLE JUDGEMENT
Check Condition
Ignition switch is "ON" position.
Judgement Criterion
The engine-ECU cannot calculate input data.
FAIL-SAFE AND BACKUP FUNCTION
Microcomputer is reset.
PROBABLE CAUSE
Failed engine-ECU
DIAGNOSIS PROCEDURE
STEP 1. M.U.T.-III diagnosis code
Reconfirmation of diagnosis code.
Q. Is diagnosis code set?
Replace the engine-ECU.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions
).