P037A
Glow Plug/Heater Indicator Control Circuit Low
Generic OBD-II
Common symptoms
What you'll notice
- Check the glow plug/heater indicator control circuit for any loose or damaged connections.
- Inspect and test the glow plug/heater relay for proper functioning and replace if necessary.
- Check the glow plugs/heater element for any signs of damage or malfunction and replace as needed.
- Ensure that the engine coolant temperature sensor is reading accurately and replace if faulty.
- Finally, inspect the glow plug/heater control module for any faults and replace if necessary.
Common causes
Most likely first
- Faulty glow plug or heater control module
- Malfunctioning glow plug or heater relay
- Wiring issues or loose connections in the glow plug/heater indicator control circuit
- Faulty engine coolant temperature sensor
- Faulty engine control module (ECM)
How to diagnose & fix
Work through it in order
- Engine misfires or struggles to start in cold weather
- Poor fuel economy
- Check engine light illuminates
- Decreased engine performance or power
- Difficulty accelerating or maintaining speed
Read & clear P037A yourself
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