Wouldn't you know it, a holiday weekend in Canada and I have a problem. This is NOT a case of a flat battery, but the engine will not crank.

It's a 2011 LML diesel:

1.
Turn on key, all the usual lights come on in the instrument panel.

2.
Wait for the glow plug light to go out, during which most of the other lights also go out. No problem so far.

3.
Only two lights remain on - the usual yellow engine light, plus the anti-theft light in red with a padlock.

4.
Turn the key to start the truck - NO CRANKING.

I've tried all of the following:

* Different key
* Checking that the truck is in Park or neutral
* Checked that the crank relay is properly seated in the fuse panel
* Tried the remote start - the tail lights flash but nothing happens when it would normally crank
* Ran the code reader - no codes

I'm thinking that the truck may be in anti-theft mode.

HINT: I just finished installing a Transfer Flow fuel tank system, so I MIGHT have disturbed somehting but I don't think so. Everything works electrically except it won't crank.

Any suggestions ??

Try cranking, if it doesn't start leave the key on for 10 minutes. After 10 minutes shut they key off and try to restart.

Where are you in Canada? Do you have the other key you can try?

Thanks for the suggestion. Being curious, I'm wondering what leaving the key turned on for 10 minutes is all about ??? I'm in Kelowna, BC, and I've already tried the other key, same result. I will try the ten minutes idea and let you know.

On older passlock systems it relearns the code. I don't think it will work with the new ones. I did a search on SI and there are no TSB's related to no start. I think a date with a tow truck is in you future.

You could also try disconnecting the batteries for 10 minutes or so and reconnect.

Yeah, I'm guessing a tow truck will be here on Tuesday. I didn't think to disconnect the batteries though - that's worth a try, thanks.

The ten minute key on didn't work. I'll try the battery disconnect tomorrow morning.

could be the ing. switch itself. wifes ss trailblazer has no crank issues sometimes and thats what it is

Has anything else been done to the truck? What does the security indicator light do when you press the unlock button?

If it needs to relearn it's a simple procedure done through the menu.

Bombdocdiesel, nothing else has been done to the truck. It is stock.

The security light stays on steady when the door unlock button is pressed. (Done with the ignition turned on).

No lights at all appear on the control panel with the ignition turned off.

I hope you get this figured out. Please let everyone know.

Normally when the newer passlocks are tripped it is from something being changed out or on the rare occasion a bad key fob. Does your security light come on after you unlock the doors before you put the key in the ignition?

Security light does NOT come on after unlocking the doors but before inserting key in ignition switch.

Sounds like you didn't disconnect the battery when installing the tank and disturbed something.

Check the nsbs.

But with the anti-theft light on when unlocked, sounds like that is it.

You may need a Tech 2 to clear it out since you have no tuning.

Sounds like you are home too, not stuck somewhere? You may get more answers in the forums.

Correct, I didn't disconnect the battery for part of the installation.

Sorry, what is nsbs?

Anti-theft light does NOT come on when unlocked.

Not stuck, at home, will likely have to wait until Tuesday for dealer help.

I had the same thing happen to my 08 LMM. Some when the headrest DVD Players were installed they spliced into a wire that wasn't supposed to be spliced into. I tried everything and thought I'd checked every fuse, had onstar try what ever it is that they can do and nothing worked. Had it towed to the dealer and they opened the fuse panel under the hood and there was a 1 amp fuse in there that was blown, I felt about this big - - anyhow, it's worth a shot and I'm sure you checked em all but hey it wouldnt hurt to check again. Oh hey, it happened to me again at a gas station when I was on the way home as well, the fuse blew and it'll continue to run until you shut it down and then it won't start again.

Try cranking, if it doesn't start leave the key on for 10 minutes. After 10 minutes shut they key off and try to restart.

Where are you in Canada? Do you have the other key you can try?



When doing the back door relearn without a tech 2 you have to do 10 min turn key off and right back on for 10 more mins then off and right on for 10 more mins on that last one turn off then turn to start. Most the time it lets the ECM and BCM relearn to each other so you have a total of around 31 mins in doing this. I did this to my 06 LBZ with a ECM from another truck with a vin that did not match mine and was acting the same as your no start and have also had other with newer truck do it and work also good luck.

Thank You Boyd823 - I did a check of fuses and relays associated with cranking, but now I'll check them all.

And ripmf666, I'll try the on/off sequence after I try battery disconnect for an hour.

OK, still no luck after:

(a) Checking all the fuses
(b) Disconnecting the batteries for an hour
(c) Doing the 30 minute "ten minute on off" suggestion.

Still looking like a tow truck will be coming

Hmm, from what I can tell you, though I'm not an expert, but have worked at a GM dealer in Montreal for one year and a half, if there is a problem with your key, let's say that the chip inside the key now gives a wrong code for whatever stupid reason it may be, and you try to start your truck more than three times without success, your truck, by default, will now stay in anti theft mode and needs to be driven back on a towing to the dealer. Whenever you make a copy of a key for your truck, the key needs to be tested at the dealer before you leave, and if it happens, just like I've seen it, the key fails to start the truck, they have to completely redo a new one. It might be a stupid thing that happened with your key, and now it just doesn't allow your anti theft mode to switch to off. Anyhow, from what I know, if your try more than 3 times to start the truck without success, you'll have to bring it back to the dealer... :( But, on the other hand, I don't understand either why, using your remote start, the anti theft doesn't switch back to off... :S

Update:

Roadside Assistance has confirmed that the passive immobilizer (anti-theft) system is preventing the vehcile from being started and the ONLY solution is to tow the truck to the dealership for reprogramming.

Thanks for all the suggestions.

Sounds like you didn't disconnect the battery when installing the tank and disturbed something.

Check the nsbs.

But with the anti-theft light on when unlocked, sounds like that is it.

You may need a Tech 2 to clear it out since you have no tuning.

Sounds like you are home too, not stuck somewhere? You may get more answers in the forums.

Hmm

colt49, it's good that you were able to get that stuff off your chest, but it's not exactly on topic. You'll be pleased to learn though that we're Snowbirds, so we'll be in the good old USA for almost 6 months as of Oct 16th, helping support that economy.

Waiting to hear what the repair will be. Its a odd one Ted...

Should know by lunchtime tomorrow, but neither the operator at Roadside Assistance, or the tow truck driver, appeared to think it was anything unusual. The tow truck driver even tried a couple of things, turning the ignition on and off, opening and closing the dorr with the key on, said "Sometimes this works". Anyway, at this stage I'm expecting to have it back mid-morning, reprogrammed.

Waiting to hear what the repair will be. Its a odd one Ted...

X2. Security/immobilizer problems in newer vehicles are somewhat rare.

So, it turns out that it was 100% my fault. Apparently, while installing the TransferFlow system, at a point where I had to cut a wire in the harness to patch in the TransferFlow tank levels sensor, I nicked a critical wire. Not sure how much this will cost me yet because they're still putting the covers on and getting it ready for me to pick up.

no longer a 911, good to see its solved

Ouch. That's gonna hurt. :(

Good to hear the solution was simple. Did they say which wire it was or what the color code is?

I'm sure that will be cheaper than finding you nicked a wire and fried an ECM.

I was too embarrassed to ask very much, but the service advisor said it was a "pink" wire. They still have the truck overnight because the chief tech wants to drive it to follow up on a different warranty issue. So I won't know the damage to my wallet until tomorrow.

Pink wire is usually related to ignition which would explain it. You would have most likely had to completely cut it though for it to quit.

what wires ( color ) did you splice into, for the fuel gauge, in the harness along the frame?

Ted glad to hear at least they found your problem. I know this isn't related to your issue but. Just a note to everyone. if you ever replace a key with a new one, this is what's done on the LML trucks. I had our Dealer cut and sent me two extra keys for our truck. On the LML's you just start the truck with one of your original keys and then turn it off remove that key and immediately put in the new key and start the truck. It learns the new key. But you must use the original key first. Just in case anyone gets a new key in the future I thought you would like to know. Good luck with the other problem Ted, maybe this Dealer can solve it and your mpg issue before you head South. Might save you some $$ in fuel

In this photo, the pinky grey colored wire, with the stripe, is the ground wire for the fuel level sender in the OEM tank.

Sorry, I've forgotten which colored wire was the sender wire, and I don't have the original instructions with me where I am for the winter.

However, if you go to the Transfer Flow website, I think you can download the instructions for the 2007 through 2010 GM and you will find the section that describes tapping in to the harness.

The color of the fuel tank sender wire is CORRECT in thos instructions, but the ground wire is INCORRECT - it needs to be the pinky grey wire shown in the photo.

The harness is the one that runs back along the outside of the frame on the driver's side.

thank you Ted