Test Step 2 - PCM Ground Circuit Test

Turn the ignition off.
Disconnect the PCM C1 harness connector.

CAUTION:

Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install the GPEC Diagnostic Adaptor to perform the diagnosis.

Fig 1: Identifying GPEC Diagnostic Adaptor

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

Connect the Adapter, GPEC Diagnostic 10436.
Using a 12 volt test light connected to 12 volts, probe the PCM ground circuits at the GPEC Adaptor.
Wiggle test each circuit during the test to check for an intermittent open in the circuit.

NOTE:

The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

Is the test lamp brightly illuminated?

Yes

Go to Test Step TEST STEP 3 - CHECK THE (A209) BATTERY SUPPLY CIRCUIT .

Repair the PCM ground circuit for an open circuit or high resistance.
Perform the PCM Verification Test. Refer to PCM VERIFICATION TEST .