Advanced Diagnostics

Advanced Diagnostics - DTC P15C4 (118): Auto Idle Stop System Malfunction






General Description
When any unit which judges permission for auto idle stop detects a malfunction that prohibits auto idle stop, they illuminate their corresponding warning indicator. If a unit with no corresponding warning indicator detects a malfunction, the powertrain control module (PCM) commands the motor control module (MCM) to illuminate the IMA system indicator and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type, OBD Status






Enable Conditions






Malfunction Threshold
The MCM detects a failure related to the auto idle stop prohibition for at least 2 seconds.

Diagnosis Details

Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the MCM memory. If the malfunction returns in the next (second) drive cycle, a Confirmed DTC and the freeze data are stored. The MIL does not come on.

Conditions for clearing the DTC
The Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the battery.