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Cooling Fan ECU

  1. Disconnect negative battery cable. Turn ignition off and wait 20 seconds. Remove cover under instrument panel. Remove lower instrument panel cover and glove box door assembly. Disconnect cooling fan ECU.
  2. Reconnect negative battery cable. Using a DVOM, measure resistance and voltage as indicated in COOLING FAN ECU SPECIFICATIONS table. Make all measurements from harness side of connector. Repair harness as necessary.
COOLING FAN ECU SPECIFICATIONS

Terminals Condition Value
1 & Ground Ignition On Battery Voltage
2 & 3 (1) 77°F (25°C) Approx. 7.8 Ohms
4 & Ground N/A Continuity
5 & Ground Throttle Valve Open No Continuity
5 & Ground Throttle Valve Closed Continuity
8 & Ground A/C Press. Sw. Disc. No Continuity
8 & Ground A/C Press. Sw. Disc. No Continuity
9 & 10 (1) 176°F (80°C) Approx. 1.52 Ohms
(1) Coolant temperature.