Door Locks Inoperative | Speedometer Repair | 2009 Dodge Charger
If your door locks stopped working and the door lock actuators are good, keep reading…
Power door locks on this vehicle are powered through the Instrument Cluster. If the MOSFETs inside have failed, some or all door locks might stop working.
- power and ground (to the speedometer)
- disconnect the speedometer’s connectors and apply power (watching current draw) to the door lock actuators circuit to make sure they are not shorted. Shorted wiring to the actuators or shorted actuators can fry a few transistors inside the Instrument Cluster.
There are three MOSFETS (2N06L13) that supply power and ground to the door lock actuators.
- Pin 3 (source) should always be 0V.
- Pin 1 (gate) should be 0V when deactivated, and 5V when activated (pressing lock or unlock button).
- Pin 2 (drain) should be 0V when deactivated, and 12V when activated (as far as I remember)
When testing MOSFETs (removed from the PCB) with a multimeter in a diode testing mode,
- good MOSFETs should show reading only between pins 3 & 2 (source and drain).
- bad ones (if shorted) will also show reading between pins 1 & 2, and 1 & 3.
If there is no 5V on pin 1 of the MOSFET in question when the unlock/lock button pressed, most likely the IC chip (4827347AA) that drives the MOSFETs (2N06L13) is toasted.
In my case, I had to replace two MOSFETs and the IC driver chip.