Faulty Coolant Pump Relay
Faulty Engine Coolant Pump
Engine Coolant Pump harness is open or shorted
Engine Coolant Pump poor electrical connection
Engine Light ON (or Service Engine Soon Warning Light)
This Diagnostic Trouble Code (DTC) is stored in the Engine Control Module (ECM) when a fault is detected with the Engine Coolant Pump circuit. An electric coolant pump is used in a vehicle with an electronically mapped cooling system. The coolant pump is controlled by a Pulse-Width Modulated (PWM) control signal. This allows for more efficient cooling control and reduced load losses on the engine. A current probe and oscilloscope can be used to monitor pump current during a diagnostic test.