My avalanche has a no crank no start ,service 4wd is displayed in the dash also a service trailer brakes is displayed in the dash .I have no communication with any modules on the truck .
I started at the ebcm ,testing ohm on my high speed data lines ,and the yellow wires are flip floppy .one minute there 120 ohms ,the next time there 253,then they will go to like a dead short to ground and this is without moving anything
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