07 Yukon ly5 fuse block issue

[wmvwebster]

So, as a background, I just did a dod delete and got the PCM tuned. After it was put back together, the starter was not engaging. So I got a new one checked all the grounds and relays and wires and decided that the s terminal wire has to have a break in it. So I put a new wire in and bypassed the old one from the starter to the people wire going into f1 on the c2 connector I think it is under the under the hood fuse block. Had battery issues so I haven't even got to fire it up yet. As I was trying to figure out the starter issue I sprayed some maf cleaner in the intake and it started to cough a little. That told me that the spark was good and that I didn't mess up the mechanical part completely. So I realized I pushed the terminal clips on the first block already and couldn't get a decent connection for my starter relay which led me to taking the things apart and squeezing them together so they fit very snug now. I was testing continuity on the relay connections and that bar under the board and noticed that the powertrain had continuity between 87 and 30 and that the board itself may be damaged and causing this. I will put up pictures. The raised part of the board is directly opposite side of the bar where it looks to be a burn discoloration right in the middle of the powertrain relay. Coincidence? Anyways, I don't want to assemble it until I get that area fixed. Any ideas? Tips on how to fix the relay, board, bar, or other parts of the picture I may be missing. I have figured the fuel delivery had not been activating due to the ecm not being informed the truck is going to start while I jump the starter. Which is why I researched extra long to find the correct pin on the connector to splice into. Please don't key it be from the delete.... I'm hoping it's something to do with the powertrain relay. Also when I try to crank it jump the relay at the fuse box I get a click from the crank relay and that's about it. Please help I just want my truck running again..

 

[mikez71]

I don't see the delete doing that to your fusebox.. Probably need a replacement fusebox is my guess..

 

[wmvwebster]

I don't see the delete doing that to your fusebox.. Probably need a replacement fusebox is my guess..

The mention of the delete was just a background on how I came to where i am (in case there is a variable that I could have missed). Moreover, I know most boards are universally fixable and this one is pretty basic. I'm just not comfortable diving in without some kind of guidance so I don't overlook something stupid. Plus the fuse blocks are like 300$ I think and I don't want to put much more money into I this truck at least until I get to drive it a while.

 

[mikez71]

Looks like almost the exact same spot this guy had a burned fusebox...
He added a jumper wire that worked in post #40..

07 LT 5.3L Sudden no start/crank

It's not comms with the BCM, it's just the ignition/key start signal. 12V. and the yellow wire is the starter relay trigger signal.. The BCM is in the middle. Here's all I can come up with.. Ignition switch "START" -> 12V to BCM (PINK J1-14) [no power? bad ignition switch] BCM -> 12V to...

www.tahoeyukonforum.com

 

[wmvwebster]

Looks like almost the exact same spot this guy had a burned fusebox...
He added a jumper wire that worked in post #40..

07 LT 5.3L Sudden no start/crank

It's not comms with the BCM, it's just the ignition/key start signal. 12V. and the yellow wire is the starter relay trigger signal.. The BCM is in the middle. Here's all I can come up with.. Ignition switch "START" -> 12V to BCM (PINK J1-14) [no power? bad ignition switch] BCM -> 12V to...

www.tahoeyukonforum.com

Dude, spot freaking on!

 

[wmvwebster]

@m

Looks like almost the exact same spot this guy had a burned fusebox...
He added a jumper wire that worked in post #40..

07 LT 5.3L Sudden no start/crank

It's not comms with the BCM, it's just the ignition/key start signal. 12V. and the yellow wire is the starter relay trigger signal.. The BCM is in the middle. Here's all I can come up with.. Ignition switch "START" -> 12V to BCM (PINK J1-14) [no power? bad ignition switch] BCM -> 12V to...

www.tahoeyukonforum.com

Same exact issue man, thank you. I just had it fire up for the first time since I started the dod delete. You have no idea how grateful I am that you found that. I'm going to eventually change the fuse block out once I know it's going to run for more than a few days. Right now I'm going to get all my tools cleaned up and let it idle for a while to make sure there are no leaks or explosions then see about test driving it.
Taking the fuse box apart and having to map out all of the relay pins to the correct connectors was mind numbing. But worth it hearing the engine come back to life again. (I didn't trust that they were all correct in the before picture I took since I had switched a few without really minding the direction they should have been in). You are a blessing mike and I'm not one to use that term loosely. Thank you. If I ever get a chance to return the gesture I won't hesitate.

 

[mikez71]

Thank you for the kind words.
Good on you and J-herkel for diving in there and sharing the story and photos!
(Looks like he is no longer here since I can't tag him)

I was surprised to see nearly the exact same bubble..
Makes me wonder it it's manufacturing defect for '07 or what?

Nice job on all the repairs! And happy to hear it fired up!