Blue Print solves common Opel and Chevrolet thermostat problem

Blue Print Protips offers practical support with everyday issues encountered in the workshop and, when possible, follows the explanation structure of ‘Problem, Cause, Solution’. Here, the company discusses a problem which can arise on certain Opel/Vauxhall and Chevrolet models, which it says can be solved using Blue Print thermostat ADG09255.

The engine cooling fan is constantly running, poor heater performance or the engine is overheating. The engine warning lamp is illuminated – related to the symptoms listed above.

These possible fault codes may be stored in the engine ECU:

  • P0597 – Thermostat heater control system – open circuit.
  • P0598 – Thermostat heater control system – circuit low.
  • P0599 – Thermostat heater control system – circuit high.

An old, or incorrect type of coolant is being used – causing corrosion or sludge buildup in the cooling system, preventing the thermostat to fully close or open. If the coolant temperature is detected to be above or below the optimum temperature range, the engine control unit has a built-in failsafe mode that will switch on the cooling fan.

Before replacing the thermostat, inspect the electrical connection and check the water temperature sensor is operating correctly. Once the thermostat has been identified as the source of the issue, flush out the coolant system and replace the thermostat. Replace the manufacturer’s recommended coolant, bleed the cooling system of any air and clear the fault codes using a suitable diagnostic tool.

Blue Print thermostat – ADG09255

To fit:

  • Chevrolet Cruze (J3), Aveo (T3)
  • Opel/Vauxhall Adam (M13), Astra J, Corsa D, Corsa E, Meriva B
  • Engines: LDC, LDD, LWD, A12XEL, A12XER, B12XEL, Z12XEP, A14XEL, A14XER, B14XEJ, B14XEL, B14XER, Z14XEP

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Published on: April 7, 2022

Filled Under: Technical Articles

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