What does code P1787 mean?

Q: What does code P1787 mean?

Reversing Light Circuit Short To Ground. P1787 on Volkswagen vehicles means the transmission control module (TCM) has detected a short to ground in the reversing light circuit, which is the electrical path that illuminates the white backup lamps when reverse gear is selected. The TCM monitors this circuit and sets the code when the voltage on the control wire is lower than expected, indicating a direct path to chassis ground.

DTC codes / Volkswagen codes / P1787

P1787 · VolkswagenReversing Light Circuit Short To Ground

P1787 on Volkswagen vehicles means the transmission control module (TCM) has detected a short to ground in the reversing light circuit, which is the electrical path that illuminates the white backup lamps when reverse gear is selected. The TCM monitors this circuit and sets the code when the voltage on the control wire is lower than expected, indicating a direct path to chassis ground.

SystemPowertrain

Code typeVolkswagen specific

SeverityMedium

Fix difficultyIntermediate

AreaTransmission

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