Diagnostic Trouble Code (DTC) Information

Diagnostic trouble code information

Condition
When the ignition is on, the central electronic module (CEM) takes a transponder reading. If the transponder responds with an unrecognized transponder code that is not approved (i.e. not stored in the memory), no transponder code or in an unrecognized communication form, the diagnostic trouble code (DTC) is generated.

Note! This diagnostic trouble code can be generated if, for example, several ignition keys hang together on the same keychain when one of them is inserted in the ignition switch.

Substitute value
Nothing.

Possible source
- The ignition key has a damaged transponder.
- The ignition key is faulty, or has no transponder
- The ignition key is a constituent of the vehicle, that is to say it has the correct security code programmed into the transponder memory, but the key's transponder code is not programmed as it has been cleared from the memory of the central electronic module (CEM).
- The ignition key is new and its transponder code has not yet been programmed into the memory of the central electronic module (CEM).
- Several similar keys are used to ensure that several transponder codes have been read during transponder reading. The result is an unknown code which is a combination of several key's transponder codes
- An electronic door key was too close to the antenna unit during locking.
- An automatic road toll transponder was installed too close to the antenna unit.
- EMC interference (powerful electrical fields) during communication stage (at start)
- The ignition key is a Volvo key, but it is for another type of Volvo.
- The ignition key is for another Volvo of the same type, that is to say it has a different transponder code. This type of key also has a different security code programmed into the transponder memory. It cannot be programmed into the central electronic module (CEM) of the vehicle in question.
- The ignition key is for another make of vehicle, that is to say it does not have the same type of transponder.

Fault symptom[s]
- The engine does not start.