P0599
Thermostat Heater Control Circuit High
Generic code
Vehicle Speed and Idle Control System
Medium severity
Hard repair
Free on OBD DashX
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What P0599 means
- The fault code P0599 indicates that there is an issue with the thermostat heater control circuit, which is registering a high voltage. This can lead to a number of engine related problems and may cause the check engine light to illuminate.
Possible symptoms
- Illuminated check engine light
- Poor engine performance
- Increased fuel consumption
- Difficulty starting the engine
Possible causes
- Failed thermostat heater control circuit
- Short circuit in the thermostat heater circuit
- Faulty wiring or connections in the circuit
- Failed engine control module (ECM)
Related parts
- Thermostat Heater: A thermostat keeps the engine at its proper temperature. __A bad thermostat leads to poor fuel economy
Possible solutions
- Replace the thermostat heater control circuit
- Check and repair any damaged wiring or connections
- Replace the engine control module (ECM) if necessary
Free on OBD DashX
P0599 on OBD DashX
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