How severe is this DTC?
The severity of this code is moderate because if the engine coolant level drops too low, the engine may overheat and cause significant damage.
What are some symptoms of the code?
Symptoms of a P2556 fault code may include:
- Cooling system warning light illuminated
- Check engine light illuminated
What are some common causes of the code?
Causes
of this P2556 code may include:
- Faulty coolant level sensor or switch
- Open or short circuit
- Faulty or damaged wiring
- Corroded, damaged, or loose connector
- Faulty fuse or fuse link (if applicable)
- Faulty PCM
What are the troubleshooting steps for P2556?
The first step in the troubleshooting process for any malfunction is to search for Technical Service Bulletins (TSBs) for the specific vehicle by year, model, and engine/transmission configuration. In some circumstances, this can save you a lot of time in the long run by pointing you in the right direction.
The second step is to locate all components associated with the engine coolant level circuit and look for obvious physical damage. Possible locations for this sensor or switch may include the coolant reservoir or overflow bottle, or the radiator. Consult a vehicle-specific repair manual to determine the location in your vehicle.
Perform a thorough visual inspection to check that the associated wiring does not have obvious defects such as scraping, rubbing, bare wires, or burn marks. Then, check connectors and connections for security, corrosion, and damaged pins. This process should include all wiring connectors and connections to all components, including the PCM. Consult vehicle-specific technical data to check the oil level safety circuit configuration and see if a fuse or fuse link is incorporated into the circuit.
Advanced Steps
Advanced steps become very vehicle-specific and require appropriate advanced equipment to perform accurately. These procedures require a digital multimeter and vehicle-specific technical references. In this situation, an oil pressure gauge may facilitate the troubleshooting process.
This article is strictly informational, and your vehicle-specific technical data and service bulletins should always take priority.