Normal Operation
WARNING: This page is about a different car, the 2010 Mercury Mariner and 2010 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
The reversing lamps relay coil ground is controlled by the PCM (automatic transaxle) or the reversing lamp switch (manual transaxle).
For vehicles with an automatic transaxle, when the transaxle is in REVERSE (R), the PCM provides ground to energize the reversing lamps relay.
For vehicles with a manual transaxle, when the transaxle is in REVERSE (R), the reversing lamps switch completes the path to ground to energize the reversing lamps relay.
When the reversing lamps relay is energized, voltage is routed to the interior rear view mirror, the Parking Aid Module (PAM) (if equipped) and the reversing lamps.
- DTC P1910 (Reverse Lamp Control Circuit/Open) - sets when the PCM detects no voltage from the reversing lamps relay coil ground control circuit (if the coil ground control circuit is short to ground).
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Reversing lamps relay
- Reversing lamp switch (manual transaxle)
- Interior rear view mirror
- PCM (automatic transaxle)