The control module detected that the Immobilizer control module state or value did not match what was expected. This is the manufacturer-specific definition used by Opel.
TuningBot DTC Database · v4.37.15
P1503 Opel - Immobilizer control module - incorrect signal
Manufacturer-specific interpretation for Opel. All interpretations of P1503
What P1503 means
Related and nearby codes
How to read P1503
Powertrain: engine, transmission and driveline systems.
Manufacturer-defined range: the meaning can differ between brands.
Specific fault index within the subsystem.
Frequently asked questions about P1503
What does P1503 mean?
Immobilizer control module - incorrect signal. The control module detected that the Immobilizer control module state or value did not match what was expected. This is the manufacturer-specific definition used by Opel.
Is P1503 generic or manufacturer-specific?
P1503 is a manufacturer-specific code. In this database it is documented for: Opel. The same number can mean something different on other brands.
Can TuningBot remove P1503 at file level?
If the fault logic lives in the ECU calibration, yes: our DTC Removal file service disables the specific fault entry. Checksum correction is not included: it is a separate, optional service. Not sure whether your case qualifies? Request a free assessment and our engineers will check your ECU file.
Other file services
Understand the system behind this code: Immobilizer Systems and ECU Pairing
