P1240

DTC P1240: Ignition Angle

TECHNICAL DESCRIPTION
Checks for an abnormal ignition timing retard angle demand signal from the active stability control (ASC).

DTC SET CONDITIONS

Check Condition
- Ignition switch is "ON" position.

Judgment Criterion
- The ignition timing retard angle demand signal is not normal.

TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- ECM failed.

DIAGNOSIS

Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991910: Main Harness A

STEP 1. Using scan tool MB991958, read the diagnostic trouble code (DTC).






CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.

1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Read the DTC.
4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the ABS-DTC or ASC-DTC set?

YES : Refer to Anti-lock Braking System - Diagnostic Trouble Code Descriptions.

NO : Replace the ECM. When the ECM is replaced, register the ID code.