LLY no start after attempting to read ecm

[blazin dmax]

Tried to read the tune out of a friend's 04.5 LLY. It got stuck and then popped up a message "bootloader rejected. Reason: controller has returned to normal operation. Please retry the operation." So I waited for the 15 second countdown and everything. Unplugged the cable from the obd2 port. Cycled the key and made sure the truck still started and it did. Turned truck off and tried again. This time it got stuck and gives me a "bootloader rejected. Reason: no response from ecm." Waited the 15 seconds and now the truck is in a no crank/no start condition. I checked all the fuses and didn't find anything blown. Unhooked battery cables for 10 minutes and that didn't help.... I'm at a loss now. Any help is greatly appreciated. Trying to get this thing on the road today.

Update. Went ahead and replaced any ecm/ignition related fuses. Still no help. Now when I turn the key to the on position. The gauges and everything come up like normal. Then they turn off like you turned the key back off. Then they power back up again. They will do this a few times and then stop like they are in the off position... Anyone ran into anything like this? I'm assuming the ecm is bricked?

 

[paint94979]

Do this it will work...

1.Turn key to the run position and leave it there
2.In the under hood fuse block pull the ECM/PCM fuse
3.Reinstall the same fuse
4.Leave the key in the run position and full flash the ECM boom.

If its an 04.5 and you dont have the stock file PM me

 

[blazin dmax]

Do this it will work...

1.Turn key to the run position and leave it there
2.In the under hood fuse block pull the ECM/PCM fuse
3.Reinstall the same fuse
4.Leave the key in the run position and full flash the ECM boom.

If its an 04.5 and you dont have the stock file PM me

Tried it. Still won't let me full flash or read the ecm. And still no crank... Thanks though. I was praying it would work. Looks like I'm buying him a new ecm... Not sure what went wrong. And now I'm gonna be scared to try and tune the truck with the new ecm...

 

[PureHybrid]

Does EFI give you a code when it fails? It should at least crank over if it doesn't start. Battery holding voltage?

 

[blazin dmax]

Doesn't give a code. Just the error message. Battery's are good. Had them on a trickle charger after I started running into problems as a precaution.

 

[elenorzx]

I had similar issues with my 01, turned out something with my remote start... Everytime I need to load a tune I have to pull the fuse on the emote start unit, does he have remote start?


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[catman3126]

just went through this 2 weeks ago. I ended up having to get a bench harness and it too the flash but somehow (and this is probably specific to this truck seem my "dead ecm" thread) it burnt up the bus bar for the ecm fuses) check to see if either side of 4-5 ecm/edu fuses have any power.

 

[blazin dmax]

just went through this 2 weeks ago. I ended up having to get a bench harness and it too the flash but somehow (and this is probably specific to this truck seem my "dead ecm" thread) it burnt up the bus bar for the ecm fuses) check to see if either side of 4-5 ecm/edu fuses have any power.

I read through your thread. The truck still has power to the fuses. Can't find any damaged or burnt up wires any where. Got a replacement ecm that I'm picking up today. Wish I had a bench harness to try and flash it with.

 

[blazin dmax]

Well the new ecm didn't do the trick. Nothing has changed... Any ideas where to start looking?

 

[blazin dmax]

Went through the vats relearn... Still no crank. Hooked up to it with efi live and it is still giving me the exact same results as with the previous ecm.

 

[paint94979]

You only read the ECM right?

 

[blazin dmax]

You only read the ECM right?

Yes. I attempted to read the ecm several times. It never completed though.

 

[blazin dmax]

Went through all the fuses again and made sure they had power. Bumped the starter relay and the truck fires, runs then dies immediately and continues to crank. Which is what it should do when you do that according to a buddy that's a tech at the dealer. So I'm ruling out the starter and batteries... Possibly the ignition switch went out? But still doesn't tell me why I can't communicate with the ecm. I have a feeling this is all stemming from the bullydog. Wonder if taking it to the dealer for a complete reflash would do anything. Thinking somthing in the bcm may be screwed up.

 

[paint94979]

The ECM is not "bricked" that I can guarantee as you haven't changed anything within the programming. It seems as though you have something else going on. You did check the cigarette lighter fuse right?

 

[blazin dmax]

The ECM is not "bricked" that I can guarantee as you haven't changed anything within the programming. It seems as though you have something else going on. You did check the cigarette lighter fuse right?

Yes I did. Even swapped the fuse and confirmed I had power there when I was checking all the other fuses.

 

[rfletes79]

Change the batteries.... I've had this same thing happen with an Lmm. Tested the batteries and checked out fine. Swapped the ECM and same thing. Ended up being cooked batteries.

 

[blazin dmax]

Change the batteries.... I've had this same thing happen with an Lmm. Tested the batteries and checked out fine. Swapped the ECM and same thing. Ended up being cooked batteries.

I will give it a shot. I don't think it is batteries since I was able to bump the starter relay and get the truck to crank and fire. But in will throw the batteries out of my truck in it and see if that makes any difference.

 

[dmax_ty]

Is there an aftermarket head unit in the truck? LLY's can be some funky buggers when it comes to aftermarket accessories and trying to flash.

 

[catman3126]

find a schematic and make sure you have power and ground to all of the pins on the blue plug. or do you know someone with a LLY that will take a flash fine. IIRC there is 4 ign 12 volts, a couple grounds and a 12 volt constant it didn't matter what I did to this last truck it was not going to take a flash. My 05 took the flash just fine the same day. bench harness all the way from now on with an LLY. don't even have to take the ecm out but that shit ain't gonna happen to me again lol.

 

[blazin dmax]

Tried different batteries out of my truck. That didn't change anything. The truck does have an aftermarket head unit but I unplugged it and the interface harness the first time I tried to read the ecm and it's been unplugged since. I'm going to get the bullydog tuner that I think is still locked to the truck for some reason and see if I can get it to do anything.