Note On Intermittents

Manipulate wiring on circuits No. 410 and No. 976 (coolant temperature sensor and PCM connector), while observing PCM parameter ED04. If failure is induced, coolant temperature will jump from normal value to the open reading (-38°C or less). Disconnect and reconnect coolant sensor and PCM connectors, and ensure they properly latch. If wiring and connectors are okay, substitute a known good sensor and retest.

Fig 1: PCM Code EO15, Schematic, Open Coolant Sensor Circuit

Fig 2: Flow Chart, PCM Code EO15, Open Coolant Sensor Circuit