Diagnostic Trouble Code (DTC) Information

Diagnostic trouble code (DTC) information

IMM-235 Key unknown

Condition

Note! Connecting the breakout box can cause diagnostic trouble code (DTC) IMM-235 to be stored. The breakout box wiring affects the signal from the transponder.




With the ignition on the immobilizer control module reads the transponder signal. Diagnostic trouble code (DTC) IMM-235 is stored 2 seconds after the ignition is switched on if the transponder responds to the immobilizer control module with an unknown and non-approved transponder code (not stored in the memory). At least one keycode must be stored in the immobilizer control module for a diagnostic trouble code (DTC) to be stored. Faults which cause diagnostic trouble code (DTC) IMM-235 can also cause diagnostic trouble code (DTC) IMM-225 to be stored.

Possible source
- The ignition key is a Volvo key which has the immobilizer control module security code programmed into the transponder memory. The key is not programmed into the immobilizer control module.
- The Volvo key is already programmed with the security code for a generation 3 immobilizer.
- Several transponders (programmed or unprogrammed) have been activated in different keys when the transponder signal is being read.
- EMC interference (strong electrical field) during the communication phase (when starting the engine).

Fault symptom[s]
- The indicator lamp in the combined instrument panel flashes.
- The engine does not start. (The starter motor does not operate).