Signal Too High. Intermittent Fault

WARNING: Before fault-tracing, disconnect engine cooling fan (FC) relay connector A so that the engine cooling fan will not run. The diagnostic trouble code (DTC) EFI-514 Engine cooling fan lowspeed, signal may be stored. After fault-tracing the connector must be reconnected.





Checking Cables and Terminals
- Check engine coolant temperature (ECT) sensor and engine control module (ECM) connectors for a loose connection, intermittent fault, contact resistance and oxidation.
- Check cable between engine coolant temperature sensor terminal 1 and engine control module # A31 for an intermittent open-circuit and an intermittent short-circuit to supply voltage.
- Check cable between engine coolant temperature sensor terminal 2 and control module # A18 for an intermittent open-circuit.
- Operation done.