What does code P0644 mean?

Q: What does code P0644 mean?

Driver Display Serial Communication Circuit. P0644 indicates that the engine control module (ECM) or body control module (BCM) has detected a communication fault on the serial data circuit that feeds the driver information display. The module monitors the data line for expected voltage levels and message traffic, and it sets this code when the circuit is open, shorted, or not responding as designed.

DTC codes / P06xx · Computer and output circuits / P0644

P0644Driver Display Serial Communication Circuit

P0644 indicates that the engine control module (ECM) or body control module (BCM) has detected a communication fault on the serial data circuit that feeds the driver information display. The module monitors the data line for expected voltage levels and message traffic, and it sets this code when the circuit is open, shorted, or not responding as designed.

SystemPowertrain

Code typeGeneric (all makes)

SeverityLow

Fix difficultyIntermediate

AreaComputer and output circuits

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.