Skip the auto shop - Our mechanics make house calls
  1. Home
  2. Articles
  3. P0598 OBD-II Trouble Code: Thermostat Heater Control Circuit Low

P0598 OBD-II Trouble Code: Thermostat Heater Control Circuit Low

Check Engine Light

P0598 OBD-II Trouble Code: Thermostat Heater Control Circuit Low

P0598 code definition

The P0598 code identifies a problem with the control circuit for the thermostat heater.

The P0598 code is often associated with the P0597 and P0599 codes.

What the P0598 code means

P0598 is the OBD-II generic code for a fault involving the thermostat heater control circuit. The thermostat heater is responsible for detecting the temperature of the engine and using that information to dictate the coolant flow through the engine. To ensure that this part is working correctly, the flow of power through the unit it monitored by the powertrain control module. If this voltage reading is low, the P0598 code will be stored in the OBD-II unit.

What causes the P0598 code?

The P0598 code has a number of common causes:

  • Faulty or corroded wiring around the thermostat
  • Faulty or corroded wiring between powertrain control unit and thermostat
  • Low coolant levels
  • Faulty thermostat
  • Faulty powertrain control module

What are the symptoms of the P0598 code?

When the P0598 code appears, the Check Engine light will illuminate on the dashboard after about three ignition cycles with the same occurring problem. In most instances of the P0598 code, there will be little to no change in vehicle performance.

When the thermostat fails, it will be stopped in the position that it was in during failure. This means that coolant flow through the engine will be stuck at the same level during vehicle operation. This could cause overheating or delayed warm-up time for the engine.

How does a mechanic diagnose the P0598 code?

A qualified and skilled technician with an OBD-II scanner capable of taking the factory readings from the vehicle. This scanner will not only show them the codes that were saved by the OBD-II unit, it will show the times at which the codes were stored. The technician will make note of these times and record the information before resetting the error codes and taking the vehicle for a test drive. If the error code was triggered by a consistent problem the error code should be stored again during the test drive.

Upon confirming the location of the issue, the technician will first check the coolant level in the engine. Once that is done, they will check the wiring on and around the circuitry for the thermostat heater. The wiring around the powertrain control module will also be inspected. They will use a voltmeter to measure the power going through the circuits.

Common mistakes when diagnosing the P0598 code

The actual components of the thermostat are often blamed for the P0598 code when the problem actually lies in the electronic components surrounding the unit. This can lead to costly repairs and the replacement of functioning components unnecessarily.

How serious is the P0598 code?

The P0598 code is moderately serious. While it does not have the potential to stop the engine or prevent it from starting, it does have the potential to damage the engine itself. While damage to the engine is unlikely, there is a risk of overheating associated with the P0598 error code. Whenever the engine overheats, components can be damaged. Have a technician diagnose the problem as soon as possible if the P0598 code appears.

What repairs can fix the P0598 code?

The most common repairs to address the P0598 code are as follows:

  • Repair or replace wiring harness around thermostat
  • Repair or replace thermostat heater
  • Repair or replace powertrain control module
  • Replace or replenish coolant in engine

Additional comments for consideration regarding the P0598 code

If there is a buildup of corrosion or other engine residue on the thermostat, then a mixture of water and baking soda can be used to clean it off.

Need help with a P0598 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
P0359 OBD-II Trouble Code: Ignition Coil I Primary/Secondary Circuit Malfunction
P0359 code definition The P0359 code indicates that a fault has been detected in one of the vehicle’s ignition coils, generally the number 9 coil. This code can also be associated...
P0608 OBD-II Trouble Code: Control Module VSS Output "A" Malfunction
P0608 means there is an malfunction in the vehicle speed sensor A control module often due too faulty speed sensor or shorted electrical wiring.

Related questions

Q: Code P02A9 Cylinder 4 Balance-Fuel Trim at Limit

The code definition specifically indicates the number four fuel injector is leaking. Fuel trims are used to indicate how much the PCM (powertrain control module) needs to adjust the fuel duty cycle to maintain the proper air fuel ratio. Duty...

Q: P0706. don't want to pay Audi $2,000. or more.

Hello and thanks for contacting YourMechanic. The dealership Audi is likely trying to sell you. I am fairly your problem is not the TCM (Transmission Control Module - transmission computer). What is wrong with your transmission is the transmission range...

Q: My car is throwing the code p0707 which means transmission range sensor I had another transmission put in same code

Hi, thanks for writing in. The transmission range sensor switch must be physically aligned with the gear selector in order to work properly. This generally involves putting the shifter in the Neutral position, then adjusting alignment of the range sensor...