P0688
Electronic Control Module Power Relay Sense Circuit/Open
Generic code
Computer Output Circuit
High severity
Hard repair
Free on OBD DashX
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What P0688 means
- The fault code P0688 indicates that there is an issue with the power relay circuit that controls the Engine Control Module (ECM) or Powertrain Control Module (PCM). This may cause the engine to run poorly or not start at all.
Possible symptoms
- Engine runs poorly or not at all
- Illuminated check engine light
- Difficulty starting the engine
- Reduced engine power or acceleration.
Possible causes
- Failed power relay
- Faulty wiring or connections in the circuit
- Loose or corroded electrical connections
- Failed ECM/PCM
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
- Replace the power relay
- Check and repair any damaged wiring or connections
- Tighten or clean any loose or corroded electrical connections
- Replace the ECM/PCM if necessary
Free on OBD DashX
P0688 on OBD DashX
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