2007 yukon 5.3 NO Crank
01-25-2016, 08:38 AM
#11
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I did swap relays with other ones . The Fuse "appears" fine however i didn't test it as this started as an intermittent issue . Ground , i tested to engine ground good , to chassis ground good
01-27-2016, 07:09 AM
#13
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yes thank you for the schematics ! definately gives me a better understanding .If i read it right, coming off the fuse going straight to the starter .i have had the under hood fuse box out 3 times looking for corrsion/bad wires etc.... ongoing
01-27-2016, 02:29 PM
#18
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Where do you see switched power on the starter SD? You have +batt 12V going through a 175A Mega fuse then to one side of the relay contacts. Pull the relay and See if you have +12v on relay socket 30. If you do jumper relay socket 30 to 87. Does starter turn? If not you have an open between relay socket 87 and starter. If starter turns then you have a bad relay, or an open ground on relay socket 85 or pcm is not putting 12V on relay socket 86 when key in crank position.
01-27-2016, 04:24 PM
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yes starter turns when jumpered , other relay in place makes no difference . Ig switch (what i think is the connector at the switch has 5 wires. no key on 2 wires are at 5 v when switched one goes to 3 v (approx) other stays the same. 3rd wire constant 12v. next two go from 0v to 12 v with key switched. nothing to compare this too but assume 2 going to 12v it likely is good and assume they go to BCM but ???? and i really do appreciate the guidance on here
01-27-2016, 04:26 PM
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