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Dead Parrot · 03-18-2018, 10:59 PM

If I read this correctly, the relay coils are switched by the PCM on the ground side. Where are the fans themselves grounded? If the fans are trying to get a ground via the PCM, could be overloading the PCM ground wire. Not a PCM expert but would think the fans would ground independent of the PCM.

03-18-2018, 10:59 PM	#2
Dead Parrot Registered User Join Date: Aug 2012 Location: Oklahoma City, OK Posts: 2,506	Re: Engine fan running 1/2 speed and relay clicking If I read this correctly, the relay coils are switched by the PCM on the ground side. Where are the fans themselves grounded? If the fans are trying to get a ground via the PCM, could be overloading the PCM ground wire. Not a PCM expert but would think the fans would ground independent of the PCM.