P0644
Driver Display Serial Communication Circuit
Generic code
Computer Output Circuit
High severity
Hard repair
Free on OBD DashX
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What P0644 means
- The fault code P0644 indicates that there is an issue with the serial communication circuit between the engine control module (ECM) and the driver display. This can cause issues with the display and may prevent the driver from receiving important information about the vehicle's performance.
Possible symptoms
- Malfunctioning driver display
- Loss of information about the vehicle's performance
- Illuminated check engine light
- Other warning lights or messages on the driver display
Possible causes
- Faulty wiring or connections in the communication circuit
- Loose or corroded electrical connections
- Failed driver display unit
- Failed engine control module (ECM)
Related parts
- Engine Control Module (ECM): ECM is the part of the car computer that controls the engine system and performance. Problems lead to poor fuel economy, engine stalling & unwanted engine vibrations
Possible solutions
- Check and repair any damaged wiring or connections in the communication circuit
- Tighten or clean any loose or corroded electrical connections
- Replace the driver display unit if necessary
- Replace the engine control module (ECM) if necessary
Free on OBD DashX
P0644 on OBD DashX
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