P1637 Diagnostic Trouble Code (7 interpretations)

The control module detected improper operation of the Motor control module (MCM) - internal circuit. This is the manufacturer-specific definition used by Honda.

The control module detected a fault associated with the CAN Link ECM ABS Control Module Circuit Network circuit or function; the stored code identifies the affected component rather than a single failure mode. This is the manufacturer-specific definition used by Jaguar.

The control module detected a fault associated with the Malfunction of Memory Backup circuit or function; the stored code identifies the affected component rather than a single failure mode. This is the manufacturer-specific definition used by Mitsubishi.

The control module detected the fault condition "ECU internal fault" for the Engine ECU. Documented for the Bosch EDC16C34 injection ECU (DV6TED4 1.6 HDi) on Peugeot applications; the same PSA control units are also fitted to Citroën models.

The control module did not receive the expected CAN data bus, electronic CE signal. This is the manufacturer-specific definition used by Audi.

The control module did not receive the expected Powertrain Data Bus signal. This is the manufacturer-specific definition used by Volkswagen. Volkswagen Group tools also report it as fault code 18045. Documented across Volkswagen Group applications (Audi, SEAT and Škoda included).

The control module detected a fault associated with the Engine control module (ECM), internal temperature high • stage 1 circuit or function; the stored code identifies the affected component rather than a single failure mode. This is the manufacturer-specific definition used by Volvo.