What does code P1678 mean?

Q: What does code P1678 mean?

Drive By Wire MIL Circuit Short To Ground. P1678 on Volkswagen vehicles means the engine control module has detected a short to ground on the drive-by-wire malfunction indicator lamp circuit, which is the warning light path for the electronic throttle system. The computer monitors the voltage on this dedicated lamp control wire and flags the code when the circuit stays at or near zero volts instead of showing the expected switched voltage.

DTC codes / Volkswagen codes / P1678

P1678 · VolkswagenDrive By Wire MIL Circuit Short To Ground

P1678 on Volkswagen vehicles means the engine control module has detected a short to ground on the drive-by-wire malfunction indicator lamp circuit, which is the warning light path for the electronic throttle system. The computer monitors the voltage on this dedicated lamp control wire and flags the code when the circuit stays at or near zero volts instead of showing the expected switched voltage.

SystemPowertrain

Code typeVolkswagen specific

SeverityMedium

Fix difficultyIntermediate

AreaComputer and output circuits

Guidance is general and written for Volkswagen vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.