Coolant Pump Control Circuit Low
The P261C code indicates that the Engine Control Module (ECM) has detected a low voltage or resistance condition in the control circuit of the electric coolant pump. This pump is responsible for circulating coolant through the engine and heater core, especially during warm-up or when the engine is off. A low circuit condition can be caused by a faulty pump, damaged wiring, poor electrical connections, or a failed ECM. This issue can lead to inadequate coolant flow, causing engine overheating and reduced heater performance.
01. Most Common Causes
- Faulty electric coolant pump
- Open or shorted wiring in the pump control circuit
- Poor electrical connection at the pump or ECM
- Failed ECM
02. Symptoms You Will Notice
- Engine overheating
- Check Engine Light illuminated
- Reduced heater output
- Coolant leaks near the pump
03. Step-by-Step Diagnosis
Step 1: Scan for additional codes and record freeze frame data.
Step 2: Visually inspect the coolant pump and wiring for damage or corrosion.
Step 3: Test the pump's electrical connector for voltage and ground using a multimeter.
Step 4: Check the pump's resistance and compare to manufacturer specifications.
Step 5: If wiring and pump are okay, test the ECM output signal to the pump.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended. Driving with a faulty coolant pump can lead to engine overheating and serious damage. Have the vehicle inspected and repaired as soon as possible.
How much does it cost to fix?▼
The cost typically ranges from $150 to $400, including parts and labor. The coolant pump itself costs $50-$150, and labor adds $100-$250 depending on the vehicle.