| Subject: | ECM Idle Learn Procedure |
When servicing the vehicle with the VIN you entered, the following diagnosis
might be helpful if the vehicle exhibits the described symptoms.
Condition/Concern:
On some 2003 and 2004 CTS vehicles, technicians may be unable to perform an
idle relearn procedure as per SI document number 813266. If no other codes or driveabilty
concerns exist, technicians should perform the following:
Recommendation/Instructions:
Idle Learn Procedure
The engine control learns the idle position of the throttle body for correct
operation. When the throttle body or ECM is replaced, this procedure must be performed
to ensure correct idle operation. The engine idle may be unstable or a DTC may set
if the idle position has not been learned. Perform the following procedure in order
to allow the ECM to learn the idle position:
- Ensure that the following conditions are met:
| • | The vehicle speed is 0 mph. |
| • | The accelerator pedal angle is less than 14.9 percent. |
| • | The battery voltage is more than 10 volts. |
| • | The engine coolant temperature (ECT) is between 5-60°C (41-140°F). |
| • | The intake air temperature (IAT) is between 5-60°C (41-140°F). |
- Turn OFF the ignition for 30 seconds.
- Turn ON the ignition, with the engine OFF for 1 minute.
- Turn OFF the ignition.
- Turn ON the ignition, clear codes if required.
Please follow this diagnosis process thoroughly and complete each step. If the
condition exhibited is resolved without completing every step, the remaining steps
do not need to be performed. If these steps do not resolve the condition, please contact
GM TAC for further diagnostic assistance. This diagnostic approach was developed for
the vehicle with the VIN you entered and should not be automatically be used for other
vehicles with similar symptoms.
Models:
(03, 04 Cadillac CTS)
