Chart C-12B, Cooling Fan, On At All Times (2 Of 4) 3.8L

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NOTE: Test numbers refer to test numbers on diagnostic charts.

Checks if circuit No. 335 is shorted to ground, keeping relay closed at all times.
Checks if circuit No. 473 is shorted to ground. An illuminated test light, indicates wire is shorted to ground.
If test light is off after disconnecting PCM, ensure circuit No. 335 is not shorted to B+. If circuit is not shorted to B+, PCM is shorted internally.
If test light is off after disconnecting PCM, ensure circuit No. 473 is not shorted to B+. If circuit is not shorted to B+, PCM is shorted internally.

Fig 1: Cooling Fan Circuit Schematic (3.8L)

Courtesy of GENERAL MOTORS CORP.

Fig 2: Cooling Fan Circuit Flow Chart, (3.8L) (2 Of 4)

Courtesy of GENERAL MOTORS CORP.