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Es250 Cooling Fan Ecu

Turn ignition off. Disconnect cooling fan ECU. See Figure. Using a DVOM, measure resistance and voltage as indicated in the COOLING FAN ECU SPECIFICATIONS  table. Make all measurements from harness side of connector. See Fig 1. Repair harness as necessary.

COOLING FAN ECU SPECIFICATIONS

Terminals Condition Value
2 & Ground N/A Continuity
3 & Ground Ignition On Battery Voltage
4 & Ground Ignition On Battery Voltage
5 & 7 (1) 176°F (80°C) Approx. 1530 Ohms
5 & 7 (1) 194°F (90°C) Approx. 1180 Ohms
5 & 7 (1) 203°F (95°C) Approx. 1030 Ohms
6 & Ground N/A Continuity
(1) Coolant temperature.
Fig 1: Identifying Cooling Fan ECU Harness Terminals (ES250)
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