What it means
Voltage on the coolant pump clutch control line is above the expected window. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
At a glance
- Usually lights the check-engine light
How it works
The coolant pump clutch control circuit carries the module's command to engage the clutch. This code sets when the module detects control-line voltage above its expected range, which can indicate an open clutch coil or a control wire shorted to battery voltage and may prevent proper pump engagement.
Common causes
Most likely first.
- Control wire shorted to B+
- Open clutch coil
- Connector pins corroded - high contact resistance
Symptoms
- Check-engine light may be on
- Engine may overheat, especially under load
- Cooling-system warning may appear
How to diagnose it
- Review freeze-frame data and live coolant temperature to see whether the high circuit reading occurred during a clutch-on command or alongside rising temperature.
- Inspect the clutch connector and control harness for damage, corrosion, loose pins, or contact with a battery-voltage wire.
- Check the control signal with a scan tool while commanding the clutch and observe whether it remains high when the module expects a different state.
- Test the control wire for an open circuit or short to battery voltage, using the manufacturer's wiring information.
- Measure clutch-coil continuity and compare the result with the manufacturer's specification to check for an open coil.
Common fixes
- Clean and secure corroded or loose connector terminals.
- Repair wiring shorted to battery voltage or an open section of control wire.
- Replace damaged connector terminals or wiring that cannot maintain a sound connection.
- Replace the clutch coil or clutch assembly if it is open and not separately serviceable.
Can I keep driving?
Avoid heavy loads and stop if the engine temperature rises or a cooling-system warning appears; the high circuit fault may prevent the clutch from engaging and lead to overheating. Arrange diagnosis promptly.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.