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elimontfort · 01-09-2015, 10:42 AM

So I have a problem ive been trying to trouble shoot and Im pretty sure it in the ecm. my problem is the fans kick on at 208 like normal but they will not shut off. temp drops to about 187 and they stay on. if I leave the truck running and I pull the relays for the fan they die when I put them back in they come back on. If I shut the truck off and start it back up they stay off till the temp gets up to 208 again then they wont shut off. Each fan is wired independently with a 30 amp relay and 40 amp fuse and gets its own signal from the ECM.

01-09-2015, 10:42 AM	#32
elimontfort Registered User Join Date: Jun 2011 Location: Sunbury, N.C Posts: 140	Re: 6.0/4l80 first start So I have a problem ive been trying to trouble shoot and Im pretty sure it in the ecm. my problem is the fans kick on at 208 like normal but they will not shut off. temp drops to about 187 and they stay on. if I leave the truck running and I pull the relays for the fan they die when I put them back in they come back on. If I shut the truck off and start it back up they stay off till the temp gets up to 208 again then they wont shut off. Each fan is wired independently with a 30 amp relay and 40 amp fuse and gets its own signal from the ECM.