What does it mean?
P1632 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Theft Deterrent Fuel Disable Signal Received .
Symptoms
- Engine cranks but will not run, or starts then shuts down after a couple of seconds
- Security or immobilizer lamp on or flashing in the cluster
- MIL (check engine lamp) on with the stored code
- No injector pulse during cranking
- Alarm behaviour: horn or lights triggering, doors locking on their own
- The vehicle may start again after a waiting period and then fail once more
Likely causes
- Theft system triggered by an unrecognised key or a forced entry or start attempt
- Transponder key not learned to the vehicle, or damaged
- Antenna ring at the ignition lock failing to read the key reliably
- Theft deterrent module faulting and sending the disable message incorrectly
- Wiring between the theft module and the engine module shorted, forcing a false disable state
- Engine module or theft module replaced without being matched to each other
- Low battery voltage causing the security handshake to fail and default to disable
How to fix it
- Try a known-good second key and note whether the engine runs
- Read the theft module and engine module and identify which one is sending and which is reporting the disable
- Inspect the ignition lock and the door locks for signs of forced entry or tampering
- Check battery and charging voltage, since weak power upsets the security handshake
- Inspect the antenna ring connector and separate other transponders from the key ring
- Test the signal line between the two modules for shorts that could be forcing the disable state
- Relearn the keys and rematch the modules with a stable power supply connected, then verify over several start attempts