P0598 Fault Code

Thermostat Heater Control Circuit Low

• What does that mean?
• Symptoms
• Causes
• Solutions

The P0598 fault code indicates a problem with the thermostat heater control circuit, which is operating at a low voltage. This circuit is crucial for regulating the engine temperature by controlling the thermostat's ability to open and close, ensuring optimal performance and efficiency. When this code is triggered, it can lead to engine overheating or suboptimal fuel efficiency.

What are the symptoms of the P0598 code?

• Engine overheating or running too cool
• Check Engine Light illuminated on the dashboard
• Erratic temperature gauge readings
• Reduced fuel efficiency
• Potential engine performance issues during warm-up

What causes the P0598 code?

• Faulty thermostat heater
• Wiring issues or short circuits in the control circuit
• Problems with the engine control module (ECM)
• Poor electrical connections or corroded terminals
• Malfunctioning sensor inputs affecting the thermostat operation

How to fix P0598?

• Inspect the thermostat heater for faults and replace if necessary
• Check wiring harness for any damage, shorts, or corrosion
• Ensure all electrical connections are secure and free from debris
• Consider testing or replacing the engine control module if issues persist
• Clear the fault code and perform a test drive to see if the code reappears