Powertrain Controls - ECM/PCM

DTC 53 Chart:

Ignition System Circuit:

CIRCUIT DESCRIPTION
The 4X reference signal is used by the PCM to determine engine RPM and crankshaft position. If the PCM does not receive fuel control reference signal pulses from the Ignition Control (IC) module for more than 0.4 second while the engine is running DTC 53 will set.

DTC 53 WILL SET WHEN
- DTC 19 and DTC 35 not set.
- No 4X reference pulse has been received by the PCM for 0.4 second.
- Engine speed greater than 568 RPM.

ACTION TAKEN (PCM WILL DEFAULT TO)
DTC does not illuminate the Malfunction Indicator Lamp (MIL) (Service Engine Soon).

DTC 53 WILL CLEAR WHEN
The fault no longer exists and the ignition switch is cycled "OFF" and ON."

DTC CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.

1. Check to see if DTC 35 is set, because a REF LO problem can cause other ignition problems.
2. Checking for power to the ignition control module.
3. Checking ignition control module ability to produce 4X reference pulses. If the system is operating correctly, you will measure 30 Hertz or greater.
4. Open at fuse block. Check terminal contact.
5. Checking for open or short to ground on CKT 430.

DIAGNOSTIC AIDS
This DTC may set due to false start condition in which engine RPM exceeds 568 but does not start.