Note On Intermittents
Manipulate wiring on circuit No. 410, coolant sensor, and ECM connector while observing ECM parameter ED04. If failure is induced, coolant temperature will jump from its normal value to the shorted reading of 148°C or greater. Disconnect and reconnect coolant sensor and ECM connectors, and ensure they properly latch. If wiring and connectors are okay, substitute a known good sensor and retest.