P0684
Glow Plug Control Module to ECM (Engine Control Module) Communication Circuit Range/Performance
Generic code
Computer Output Circuit
High severity
Hard repair
Free on OBD DashX
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What P0684 means
- The fault code P0684 indicates that there is a problem in communication between Glowplug control module and ECM.
Possible symptoms
- Difficulty in starting the engine
- Illuminated check engine light
- Poor engine performance
- Rough idle or stalling.
Possible causes
- Faulty glow plug control module
- Damaged or corroded wiring in the circuit between Glow plug module and ECM
- Failed engine control module (ECM)
Related parts
- Glow Plug: A glowplug is a heating device that helps to start diesel engines. This car's glow plug has a problem which may cause hesitation while starting the car or the car not starting at all
Possible solutions
- Replace the glow plug control module
- Inspect and repair any damaged or corroded wiring in the circuit between these two modules.
- Replace the engine control module (ECM) if necessary
Free on OBD DashX
P0684 on OBD DashX
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