What does it mean?
P1650 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Output Driver Module Circuit Malfunction .
Symptoms
- MIL on, usually with companion codes naming the specific device that failed
- One or more electrically controlled devices stop working: a relay, an EVAP solenoid, a cooling fan or a warning lamp
- Erratic operation of accessories, or a device that works only when cold
- Repeatedly blown fuses on the affected circuit
- Depending on which output is affected, reduced power or a limp-mode strategy
Likely causes
- A shorted solenoid, relay coil or indicator lamp on that driver group pulling the output down
- Control wire chafed and shorted to ground or to battery positive
- Corroded connector or backed-out pin at one of the controlled devices
- Blown fuse on a shared supply feed leaving a device unpowered
- Water intrusion at the module connector
- An aftermarket accessory wired into a module-controlled output
- Failed output driver inside the module itself
How to fix it
- Record every stored code; the companion codes usually identify which output is at fault
- Unplug each solenoid, relay and lamp on that driver group and measure coil resistance against specification
- Command each output with the scan tool and note which one does not respond
- With the device unplugged, test its control wire for shorts to ground and to battery voltage, and for an open circuit
- Inspect the module connectors for moisture, corrosion, spread terminals and pushed-out pins
- Repair the shorted or open circuit, clear the code and re-run the output tests
- Replace and program the module only when every external short and open has been ruled out