Hi all, I am having trouble where my 2008 Silverado 1500 won't turnover with the key in the crank position. The dash lights and gauges engage as if it i cranking but the starter does not do anything. I have had the battery and starter/solenoid tested. They came out fine. I have put a test light on the starter solenoid wire connector and there is no power there with key in the crank position. Anyone have any thoughts what I need to check next? Thanks.

 

Check the fuses and the start relay.

 

Thanks for the reply. My apologies, I meant to include that the fuses and relays were checked, as well. All came out fine.

 

To make sure I am being clear - when I turn the key to the "on" position, all gauges/ gauge lights in the instrument cluster activate. When I turn the key all the way forward to the "start" position, all gauge/ gauge lights in the instrument cluster go blank. That includes the 'anti theft/security" light. At that point the starter/solenoid does nothing and I get no power to the solenoid

 

I did an OBD scan today and got code U0100 (Lost communication with ECM/PCM). I also tested the fuses under the hood with a test light. Fuses 4, 8, 13, 18 and 24 are not getting any power. They are all aligned in the same column one below the other. Fuse 4 is the engine fuse. Wiring looks good. Seems like the ECM may be out. Anyone with any thoughts? Thanks.

 

I had this happen to me once while out shopping .
Exact same symptoms .
What I found on my 2007 was there were loose connections under the underHOOD fuse block and several fuses that were corroded in half with corroded terminals in the upper fuse block assy .
I had to remove the Negative battery cable for a while so I could go through the entire fuse block and by one and remove the fuses and test them all with an Ohmmeter and applied an anti corrosive compound ( similar to vaseline to keep the air off the terminal surfaces and prevent further corrosion) to each fuse terminal and relay socket . In total I had 5 rotted fuses and 3 corroded relay terminal sockets . I used Q-tips and a small straight blades screwdriver to apply the compound into the fuse base sockets .
I also applied the same compound to the harness connectors under the fuse block to prevent those connections from corroding . the fuse and relay block will separate from the terminal half by actuating the Two GRAY handles One in front and one in rear . Also you may find it easier to do by removing the angle brace from the fender and firewall by removing the 4 bolts that hold it in place ( not required but nice to not have to work around the brace) Also the compound I used will remain pliable and Not harden (Critical consideration on any type of connection that is subjected to vibrations and will crack if hardened and allow corrosive agents into the connection )
Personally I prefer a product made by “Truck-Lite” “NYK-77” I found mine at “Findittruckparts.com”
After having done this I replaced the Negative battery cable and life has been good .
I hope this long winded reply helps you find your phantom . and fix the issue as well as head off any future issues .

 

Ok, thanks rcorn1031; I will pull the underhood fuse block and check it out.

 

If after you get done doing the checks suggested by icorn, if that didn't solve the problem,

I believe there is a problem involving the anti theft system.

If you have a second working key, you might try that. Sometimes coded keys go on vacation and stop working.

What you describe regarding the starter solenoid is typical of a security system problem.

 

Thanks hanky, I will definitely check one of the other keys. How should the light react when the vehicle is in the "on" and "start/crank" positions? Also, I failed to mention that I do not see a "check engine" light or symbol light up at all in the "on" or the "start/crank" positions. Shouldn't it come on at least temporarily in the "on" position? Thanks.

 

Hi all, I finally got around to checking all the underhood fuses in my 2008 Silverado. I pulled the box and did not find any corrosion on any of them. I checked all the fuses with a test light and all are getting power on both sides except Fuses 4, 8, 13, 18 and 24 are not getting any power (as mentioned before). I also checked the BCM fuse on the driver side of the dash it's getting power on both sides. I tried to crank the truck with my spare key and still no start. I pulled the ecm and I am told the hardware tested fine. Not sure what to check next. I appreciate any comments. Any wiring diagrams available? Thanks.