Glow Plug Control Module 2 to PCM Communication Circuit

Common symptoms

What you'll notice

• Check for any loose or damaged connections between the glow plug control module and the PCM (Powertrain Control Module).
• Inspect the glow plug control module for any signs of damage or malfunction and replace if necessary.
• Test the PCM to ensure proper communication with the glow plug control module and replace if faulty.
• Verify that the glow plugs are functioning correctly and replace any faulty ones.
• Reset the vehicle's ECU (Engine Control Unit) to clear any potential error codes and see if the issue persists.

Common causes

Most likely first

1. Faulty glow plug control module
2. Wiring or connection issues between the glow plug control module and PCM
3. Defective PCM (Powertrain Control Module)
4. Malfunctioning glow plugs
5. Faulty communication circuit between the glow plug control module and PCM

How to diagnose & fix

Work through it in order

1. Engine misfire or rough idling
2. Difficulty starting the engine
3. Reduced engine power or acceleration
4. Poor fuel efficiency
5. Illuminated check engine light