P0012

DTC P0012: Camshaft Position - Timing Over-Retarded

TECHNICAL DESCRIPTION
- If the vehicle equipped with 4B11-T/C engine continues the rough driving like competitive running (the running that constantly repeats the cycle of the full opened position of the accelerator pedal and the full closed position of the accelerator pedal.), the amount of carbon mixed into the engine oil tends to increase. This can possibly cause the timing chain to gradually elongate. To prevent this, the function or logic monitoring the amount of elongation of the timing chain is integrated into the ECM. The details are shown in timing chain maintenance.

DTC SET CONDITIONS

Check Condition
- Ignition switch is "ON" position.

Judgment Criterion
- The learning value for the current phase angle of V.V.T. at the intake (retard angle) side and the exhaust (advanced angle) side is different from the initial phase angle of V.V.T. by more than the specified value.

FAIL-SAFE AND BACKUP FUNCTION
- None

TROUBLESHOOTING HINTS (The most likely causes for this code to be set are: )
- Timing chain elongated.

DIAGNOSIS

STEP 1. Timing Chain Elongation Visual Check

Q: Are there any abnormalities?

YES : Initialize the learning value for the elongation of the timing chain.

NO : Replace the timing chain and the oil pump chain. Then initialize the learning value for the elongation of the timing chain.