The P261C: Coolant Pump ‘B’ Control Circuit High code indicates that there is a higher than expected voltage or signal detected in the coolant pump ‘B’ control circuit. This issue can impact the proper functioning of the secondary coolant pump, which is essential for regulating engine temperature, particularly under heavy loads or in specific cooling applications.
P261C – Quick Overview
| Code | Information |
|---|---|
| Meaning | P261C: Coolant Pump ‘B’ Control Circuit High |
| Is it serious? | Yes, high voltage can lead to malfunction or potential damage to the coolant pump, which may result in inadequate cooling and engine overheating. |
| Possible causes | – High voltage or signal in the coolant pump ‘B’ control circuit – Faulty coolant pump ‘B’ control system – Wiring or connector issues |
| How to diagnose? | – Measure the voltage in the coolant pump ‘B’ control circuit – Inspect and test the coolant pump ‘B’ control system – Check wiring and connectors – Replace faulty components if needed |
P261C Meaning
The P261C: Coolant Pump ‘B’ Control Circuit High code means that the control circuit for Coolant Pump ‘B’ is experiencing an abnormally high voltage. Coolant Pump ‘B’ is a secondary pump used to maintain proper coolant circulation, especially under high load or for specific components. High voltage can indicate an electrical issue, such as a short circuit, a failing control module, or a fault in the wiring. Left unaddressed, this may lead to pump failure or ineffective cooling, causing engine overheating.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to see if there are any other related codes. Additional codes might help provide a more complete picture of the issue. | OBD-II Scanner |
| Measure Voltage in Coolant Pump ‘B’ Circuit | Use a multimeter to measure the voltage in the coolant pump ‘B’ control circuit. Compare the reading to manufacturer specifications to determine if the voltage is above the acceptable range. | Multimeter, Diagnostic Tool |
| Inspect Coolant Pump ‘B’ | Inspect Coolant Pump ‘B’ for any physical damage, such as cracks or overheating. Verify that the pump is properly installed and not blocked. | Flashlight, Safety Gloves |
| Check Wiring and Connectors | Inspect all wiring and connectors associated with Coolant Pump ‘B’. Look for signs of frayed wires, corrosion, or poor connections that could result in a high voltage condition. Repair as needed. | Flashlight, Multimeter |
| Replace Faulty Components | If the coolant pump, control module, or wiring is found to be faulty, replace the defective parts with components that meet manufacturer specifications. | Replacement Parts |
| Clear the Code and Test System | Use an OBD-II scanner to clear the P261C code after completing repairs. Start the engine and monitor the coolant pump’s operation to ensure that it is functioning correctly. | OBD-II Scanner, Vehicle Owner’s Manual |
| Recheck for Codes | Re-scan the vehicle to verify that the P261C code has been successfully cleared. If the code returns, further diagnostics will be needed to pinpoint the remaining issue. | OBD-II Scanner |
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