Result:

p1637

Audi
Type:
    Powertrain - Manufacturer Controlled DTC - Manufacturer Controlled
Description:
    CAN data bus, electronic CE - no signal
Cause:
    Trouble code(s) stored, wiring, matching resistor in ECM

GM
Type:
    Powertrain - Manufacturer Controlled DTC - Manufacturer Controlled
Description:
    Generator 'L' Terminal Circuit Conditions
Cause:
    Engine running, then the PCM detected the state of 'L' terminal feedback indicated low Generator system voltage for 15 seconds

Volkswagen
Type:
    Powertrain - Manufacturer Controlled DTC - Manufacturer Controlled
Description:
    CAN data bus, electronic CE - no signal
Cause:
    Trouble code(s) stored, wiring, matching resistor in ECM

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