I disconnected the extra grounds and it still cranks the same. Won’t crank every time but when it does it runs about 3 seconds. It will accelerate and go into gear but you have to be fast. The sensor you said wasn’t necessary, I’ll try unplugging it and maybe change the cable out. Maybe I can find someone else who has had this problem. I got my wife to beat on the fuse box after I got it started but no change. I also loosened and retightened the connections to the ECM and no change. Gauges still not working.
Another 2011 Tahoe won’t crank
- Thread starter OLEJOE
- Start date
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intheburbs
Full Access Member
Wonder if this might be related to the Pass-Key system? I know it's not an apples-to-apples comparison, but I was programming a new key to one of my Jeep Wranglers, and the programming didn't work the first time. The Jeep would start, run, then die after 3 seconds with the un-programmed key.
I don’t know but I did the 30 minute relearn and it didn’t help. It’s so random about when it starts. It doesn’t crank every time and the gauges not working makes me think they are not getting connected to the motor or body of the truck. I’ve got someone else going to come by and take a look. He has a better scan tool than mine and maybe his will shed some light on it. He’s a diesel mechanic by trade but he knows a lot of good mechanics and said he would call them and see if they have ever run in to this. Thanks for the help so far. I will definitely post back if we get it going.
Well didn’t get anything done today but had the battery load checked. Good there. My friend got hold of his mechanic buddy and he is going to loan him his Tech2 scanner and going to try it tomorrow. We’ve all been combing the internet and think it is a security system problem. The ignition switch, BCM, path to ECU or ECU itself. The only way I’ve been able to get it to crank is by inserting the key and turning it to start very quickly in 1 motion. I’m thinking the security system is in the process of trying to verify the key and when it can’t it isn’t sending a signal to the ECU to continue running the fuel pump. I’m leaning more toward the BCM because the gauges still not working. Maybe the Tech 2 scanner will tell us something.
When you have the tech2 hooked up I believe you will want to look in the bcm for the "starterkill" command and see if it says yes/no or true/false, there is a security sensor that goes around the ignition that reads the key sends the signal to enable or disable the starter.
mine is a little goofy whenever the battery is discontented, I have disconnect the battery a 2nd time and get any static power killed then reconnect the battery for it to start and it doesn't give any codes when it does it other than I can see with the tec2 that the starter is disabled.
Well nothing to report today. I did change out the ground cable because it didn’t fit the battery terminal as tight as I would have liked but it didn’t help. I pulled every fuse and checked with ohm meter, all good. I don’t think it is in the security system. I enabled it and it works just like the owner manual says. Had a friend come over who’s a computer and electronics wizard and he took the BCM out and took it apart and checked every solder joint and said it looked good but he couldn’t test each component to make sure they were operating. Checked the transmission connections and they all look good. Got under it on a creeper and checked every inch of loom to see if any were broken or melted or disconnected and found nothing. Checked continuity between engine and body, all good. May be able to get the Tech 2 tomorrow or Saturday and see if it shows any thing. Still cranks every now and then, runs great for about 3 or 4 seconds and then won’t turn over or start. ??????
Gauges still not working either.
Gauges still not working either.
