P0597Medium urgency

Thermostat Heater Control Circuit Open

Engine · Cooling System

⚠️ Engine may run too cold or at a fixed temperature. Fuel economy suffers. Service within 1–2 weeks.
What this means

The electronically controlled thermostat heater has an open circuit. Map-controlled thermostats use an internal heater to vary opening temperature based on engine load — an open heater circuit locks the thermostat at one temperature.

Likely causes
  • Failed electronically controlled thermostatMost common
  • Open heater circuit wiringCommon
  • Blown thermostat heater fuseLess common
Estimated repair cost
Electronic thermostat replacement$80 – $300
Wiring repair$80 – $200
Fuse replacement$5 – $20
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Frequently asked questions about P0597

What does P0597 mean?

The electronically controlled thermostat heater has an open circuit. Map-controlled thermostats use an internal heater to vary opening temperature based on engine load — an open heater circuit locks the thermostat at one temperature.

Is P0597 serious?

Engine may run too cold or at a fixed temperature. Fuel economy suffers. Service within 1–2 weeks.

How much does it cost to fix P0597?

Repair costs for P0597 range from $80 – $300 depending on the root cause and your vehicle.

Can I drive with P0597?

You can drive short distances but should have it repaired within 1–2 weeks to prevent further damage.

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