GM Crankshaft Position Sensor Variation Relearn Guide

control module was replace,you must to do CKP sensor learning.So this instruction show the procedures of how to perform the Crankshaft Position Sensor variation relearn.And for more projects about GM,check here:GM vehicle repair cases

 

WARNING: High RPM is required for the learning procedure. Run the procedure in Park or Neutral with the drive wheels blocked and the parking brake applied.

 

– Fuel RPM Calibration Cutoff Values –

Passenger Cars Light Duty Trucks

————– —————–

L4: 3970 RPM L4: 3970 RPM

V6: 5150 RPM V6: 4000 RPM

V8: 4000 RPM V8: 4000 RPM

 

Engine should not accelerate beyond the calibrated RPM value.

Release the throttle immediately if the RPM exceeds these values during the procedure.

If the procedure does not complete, read the DTC’s and perform appropriate repair.

 

Crankshaft Position (CKP) Sensor Variation Learn Procedure (4.3L, 5.0L, 5.7L & 7.4L Except Calif.)

1) Install the SPS device on Data Link Connector (DLC). Apply parking brake. Block rear wheels. Ensure hood is closed.

2) Place transmission in Park (A/T models) or Neutral (M/T models). Start engine and warm engine until engine coolant temperature is at least 150 Deg F (65 Deg C). Ensure all accessories are off.

3) Apply service brakes. With engine idling, use the SPS Device to enable CKP sensor variation learn procedure.

CAUTION: Ensure throttle is quickly released to idle position once CKP sensor variation learn procedure fuel cut off is obtained and engine starts to decelerate.

 

IMPORTANT: After the ignition switch is turned to the CRANK position, the VCM must see a change in the state of brake switch (released to applied) to run the learn procedure. Also,

the service brakes, and the parking brake must be held throughout the duration of the learn procedure.

4) Gradually accelerate engine to required RPM. Quickly release throttle to idle position once CKP sensor variation learn procedure is obtained and engine starts to decelerate. Once CKP sensor variation values are learned, the VCM will return engine control to the operator and engine will respond to throttle position.

5) If CKP sensor variation learn procedure was completed, turn ignition off for at least 15 seconds and remove scan tool. If CKP sensor variation learn procedure was not completed, a DTC P1336 should be stored in the VCM. Analyze controller for DTC P1336 and repair as necessary.