2010 Yukon XL 5.3 No Power to Coil

[slyhog022056]

Hello again people. I am trying to get my 10 Yukon back running again. It was crashed and totalled a few months back but still ran. Replaced needed and got it going. I was driving it around over 200+ miles to set the IM for vehicle inspection. Ran fine until all of a sudden it had a cyl 4 misfire and the usual traction control lights come up. Checked for spark and had none. Swapped coil, plug wire and plug... Nothing. Called a GM tech and he gave me general voltage info at the coil plug pin 1 gnd, pin 2 12vdc. I only have ground, not 12 volt reference, no trigger signal. I want to trace out the wires but cant find a wiring diagram with the correct pinouts at the ecu and coil. all I can find id the wiring to IC4 control pin #76 Dk Grn/ Wh. that much i understand. the plug on the coil does not have a Dk Grn/ white wire on it. I want to try and trace out this circuit before I have to spend $250 for another ECU.

 

[Doubeleive]

Hello again people. I am trying to get my 10 Yukon back running again. It was crashed and totalled a few months back but still ran. Replaced needed and got it going. I was driving it around over 200+ miles to set the IM for vehicle inspection. Ran fine until all of a sudden it had a cyl 4 misfire and the usual traction control lights come up. Checked for spark and had none. Swapped coil, plug wire and plug... Nothing. Called a GM tech and he gave me general voltage info at the coil plug pin 1 gnd, pin 2 12vdc. I only have ground, not 12 volt reference, no trigger signal. I want to trace out the wires but cant find a wiring diagram with the correct pinouts at the ecu and coil. all I can find id the wiring to IC4 control pin #76 Dk Grn/ Wh. that much i understand. the plug on the coil does not have a Dk Grn/ white wire on it. I want to try and trace out this circuit before I have to spend $250 for another ECU.

the coil pack harness is where you want to start, the harness can be replaced if determined to be bad, or fix the break in the wire.
usually it is the ground that goes bad

 

[mikez71]