P0598: Thermostat Heater Control Circuit Low
12 vehicles · 7 makes · $60-$5,000 repair
Most Reported On
P0598 is an OBD-II diagnostic trouble code meaning “Thermostat Heater Control Circuit Low.” This code applies to engines with an electronically controlled (heated) thermostat and means the Powertrain Control Module detected an abnormally low voltage in the thermostat heater control circuit. The heater element lets the computer fine-tune coolant temperature for efficiency and emissions by opening the thermostat sooner under certain conditions. P0598 sets when the control or feedback circuit reads lower than expected (often a short to ground or loss of supply). It is found mainly on certain European makes (BMW, Mercedes, VW/Audi, etc.) and usually has little effect on driving. This code is most commonly reported on 2007-2016 MINI Cooper, 2009-2020 Audi A4, and 2012-2018 Audi A7 (Premium Plus, Prestige), plus 9 other vehicles, with repair costs ranging from $60 to $5,000.
Common Causes
Typical Repair Cost
Based on 13 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.
Diagnostic Tools
To diagnose P0598, you'll need an OBD-II scanner. Here are our recommendations at every price point.
ANCEL AD310 Classic OBD-II Scanner
by ANCEL
A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).
- Read & clear engine codes
- View freeze frame data
- I/M readiness status
- No batteries or app needed
BlueDriver Pro Bluetooth Scanner
by BlueDriver
Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.
- Enhanced diagnostics (ABS, SRS, transmission)
- Repair Reports with verified fixes
- Smog check readiness
- Free app (iOS & Android)
LAUNCH CRP123X OBD-II Scanner
by LAUNCH
A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.
- Engine, transmission, ABS, SRS diagnostics
- Live data stream & graphing
- AutoVIN for vehicle identification
- Free lifetime updates via Wi-Fi
Autel MaxiCOM MK808S Diagnostic Tool
by Autel
Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.
- All-system diagnostics (25+ modules)
- Bi-directional control & active tests
- Oil reset, EPB, BMS, TPMS, injector coding
- 7-inch touchscreen with Android OS
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Vehicles Affected (12)
Water Pump/Thermostat Failure
Thermostat Housing Coolant Leak
Coolant Leaks (Thermostat Housing and Hoses)
Water Pump and Thermostat Failure (Overheating)
Thermostat Housing Coolant Leak / Cracking
Engine Overheating / Water Pump and Radiator Fan Failure
Thermostat Housing Coolant Leak
Engine Overheating / Cooling System Failures
FAQ
What does P0598 mean?
P0598 stands for "Thermostat Heater Control Circuit Low." This code applies to engines with an electronically controlled (heated) thermostat and means the Powertrain Control Module detected an abnormally low voltage in the thermostat heater control circuit. The heater element lets the computer fine-tune coolant temperature for efficiency and emissions by opening the thermostat sooner under certain conditions. P0598 sets when the control or feedback circuit reads lower than expected (often a short to ground or loss of supply). It is found mainly on certain European makes (BMW, Mercedes, VW/Audi, etc.) and usually has little effect on driving.
What are the most common causes of P0598?
The most common causes of P0598 are: Faulty electronically controlled (map-controlled) thermostat, Short to ground in the heater control wiring, Corroded or loose thermostat connector, Open or damaged wiring in the control circuit, Low coolant level overheating the thermostat heater, Blown fuse or poor power supply to the circuit, Faulty PCM control driver. The specific cause varies by vehicle.
How much does it cost to fix P0598?
Repair costs for P0598 range from $60 to $5,000, depending on the vehicle and root cause.
Which vehicles are affected by P0598?
Au7o has documented P0598 across 12 vehicle models from 7 manufacturers: Audi, BMW, Chevrolet, Dodge, Jeep, MINI, Skoda.
Sources (12)
- NHTSANHTSA Complaint #11408357 - 2017 Audi A4 coolant pump/water pump failure
- ForumJeepPatriot.com - Thermostat Housing Discussion
- newsMyJeepPatriot.com - Common Problems and Solutions
- partOEM Thermostat Housing Assembly 68003582AB
- NHTSACarComplaints.com - 2006 Commander Engine & Cooling (173 complaints)
- mediaDodge Caliber Overheating - 700R4TransmissionHQ
- mediaDodge Caliber Running Hot - 700R4TransmissionHQ
- ForumOverheating issue needing help - Dodge Caliber Forums
- ForumWheres the radiator fluid going - Dodge Caliber Forum
- NHTSANHTSA Vehicle Complaints for 2016 BMW X1
- videoBMW F48 X1 Electric Water Pump Replacement - DIY Repair
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.