P0597 Code: Thermostat Heater Control Circuit / Open - In The Garage with CarParts.com (2024)

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The thermostat is the valve that helps regulate the engine’s temperature. It ensures the engine gets hot enough to do its job without running the risk of overheating by controlling the flow of coolant fluid to the radiator for waste heat disposal.

While older engines use mechanical means to adjust their thermostats, newer designs use electronic thermostats directed by the powertrain control module (PCM) for greater efficiency.

If the computer receives an erroneous signal from the thermostat that indicates zero control voltage, its onboard diagnostics will set a P0597 code.

What Does the P0597 Code Mean?

Diagnostic trouble code (DTC) P0597 code stands for “Thermostat Heater Control Circuit/Open.”

An electronic thermostat consists of a control housing that contains the valve itself and sensors that constantly measure the engine temperature. The sensors deliver their readings to the PCM, which adjusts the thermostat’s position accordingly. The computer also keeps track of the valve’s feedback voltage to determine if the electronic circuit is open, shorted to ground, or shorted to a voltage source.

When the thermostat’s signal does not show the correct voltage for a specific amount of time, the PCM will log a thermostat heater control circuit code. Among these codes, the P0597 code warns that the electronic valve’s control voltage is zero.

P0597 on Some Chevrolet Vehicles

Code P0597 may appear on some Chevrolet vehicles like the 2012 Chevrolet Cruze LS 1.8L, L4.

Conditions for running DTC P0597 in a 2012 Chevy Cruze LS can include:

• The ignition is ON, or the engine is running.
• The ignition voltage is greater than 9 V.
• DTC P0597 00 runs continuously once the above conditions are met.

The DTC is set when the ECM detects that the commanded state of the driver and the actual state of the control circuit do not match for greater than 15 seconds.

Note: The definition of code P0597 may vary depending on the vehicle manufacturer. Consult the right repair manual or repair database for the exact code definition.

What are the Possible Causes of the P0597 Code?

• Faulty thermostat
• Problems with the thermostat wiring
• Faulty powertrain control module (PCM)

What are the Common Symptoms of the P0597 Code?

• The radiator‘s cooling fans may continue to run even when they’re not needed
• Check engine light illuminates
• Engine temperature gauge shows abnormally high or low readings because the thermostat failed in a partly open or close position

How to Diagnose the P0597 Code

A DTC P0123 is a generic powertrain trouble code that may be set in vehicles with an electronic engine thermostat. While these vehicles may show similar triggers and symptoms, the steps for diagnosis and repair may vary between different makes and models.

If you lack experience or knowledge on how to run diagnostic tests on your vehicle, you should consider bringing it to a professional mechanic. Otherwise, you may go ahead and diagnose the issue yourself. To help you get started, here are some videos that may give you an idea of what the process might involve:

How to Fix the P0597 Code

Attempting to fix a P0597 code may become a frustrating task if you don’t have the right tools and know-how to test the thermostat. In most cases, it’s best to leave the job to professionals.

If you’re a DIYer with advanced technical knowledge and hands-on experience, you may test and replace your vehicle’s electronic thermostat on your own. Consult repair manuals for reference. Rely on guides that provide vehicle-specific information to avoid mistakes that can escalate the problem.

Where to Get a New Thermostat to Fix DTC P0597

DTC P0597 is typically logged when the thermostat malfunctions. It’s not a good idea to hold off on replacing it because it can make driving a hassle. For a top-notch replacement thermostat that’ll give you the best value for your money, shop here at CarParts.com.

Our website makes it easy for car owners like you to find the right parts for your ride. Use our vehicle selector to start shopping, and funnel the catalog results according to your preferred brand, price, and specs using the search filters. On top of that, all our thermostats come with a low-price and lifetime replacement guarantee.

We make sure to get our auto parts from the most trusted manufacturers in the industry. All our parts pass the highest quality control standards from industry professionals, so you won’t have to worry about any replacements you order failing you any time soon.

Don’t leave DTC P0597 unaddressed. Shop for a new thermostat today!

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File Under : OBD-II Trouble Codes Tagged With : thermostat