Pcm Coding: Notes

NOTE: VAG 1551 scan tool is necessary to perform PCM coding.

NOTE: After coding PCM and starting engine for first time, allow engine to idle for several minutes so PCM can go through a learn function. Idle speed may be erratic while PCM is learning.

If Powertrain Control Module (PCM) is replaced it is necessary to code new PCM. If new PCM is not properly coded, the following problems may occur:

Driveability problems (i.e. harsh shifting).
Increased fuel consumption.
Increased exhaust emissions.
Reduction in transmission life.
Malfunctions not present are stored in PCM memory.
All PCM functions are not carried out (i.e. EVAP system operation).

Following manufacturers instructions, connect VAG 1551 scan tool to vehicle. Following manufacturers instructions, access PCM coding information using VAG 1551 scan tool. For PCM coding options, see the PCM CODING OPTIONS table.

As an example, a properly coded PCM for a model with EGR system, All Wheel Drive (AWD) and Automatic Transmission (A/T) would look like 01251 on the VAG 1551 scan tool.