LMM Duramax from hell!!!

LBZ_Baker98

Member
Jul 8, 2016
207
2
18
Texas
So we've had a 09 LMM dually for awhile now that no one can figure out. It started with blowing the DLIS (2amp) fuse randomly it progressively got worse where the fuse would blow as soon as you turn the key on. We were able to throw a slightly bigger fuse in the truck to get it started to get it on the trailer and home. Now the DLIS fuse doesn't blow when the key is turned on and the truck won't start unless you jump the starter. If you jump the starter truck will run great. It's throwing codes P2510,u1041,u0140,P2536. Replaced ignition no change. Replaced TCM. No change. Replaced BCM but can't do the 30 mins key cycle to marry it to ECM. Truck still runs if you jump the starter. Spent countless hours tracing wires. When you turn the key off and open the door the radio and interior lights stay on. You have to disconnect batteries to get them to go off. We are at a loss any help is greatly appreciated!
 

torqued2dmax

Member
Mar 26, 2017
646
1
18
Brookville, PA
I have a Jeep Grand Cherokee that had the same problems , I know do not hate on me yet Sometimes when you hit the key , nothing , next time it was ok then the dome lights would not go out then the radio would stay on then the compass would go off and on then the high beam indicator quit working , when you mentioned open the door , well I found after much searching 4 partially broken wires in the drivers door and 2 in the passenger door , they were broken inside the shielding , sometimes they would make contact and sometimes no , now they are fixed and all the problems are gone ! Good Luck !
 

TheBac

Why do I keep doing this?
Staff member
Apr 19, 2008
15,271
1,565
113
Mid Michigan
You should use a Tech2 or equiv to check data transmission across the different modules.

Do you have any aftermarket modules like an alarm installed on the truck?
 

LBZ_Baker98

Member
Jul 8, 2016
207
2
18
Texas
You should use a Tech2 or equiv to check data transmission across the different modules.

Do you have any aftermarket modules like an alarm installed on the truck?

No after market modules. Been trying to get ahold of a tech 2 but you know how that goes. Could it maybe just need the BCM programmed the fuse that was originally blowing quit blowing after the BCM was replaced!
 

LBZ_Baker98

Member
Jul 8, 2016
207
2
18
Texas
Does anyone think maybe the BCM just needs to be programmed? Since the BCM was replaced it quit blowing the DLIS fuse but truck won't start with key. BCM has not been programmed at all since replacement
 

2004LB7

Well-known member
Dec 15, 2010
6,282
1,683
113
Norcal
Well, have you tried the relearn process? Was the BCM used or new? If used was it from the same vehicle type?
 

2004LB7

Well-known member
Dec 15, 2010
6,282
1,683
113
Norcal
If new you will need to get the truck to the dealership and have them programe it. Wont run otherwise. Ben here may also be able to help you on this too as he has the capability of programming BCMs
 

LBZ_Baker98

Member
Jul 8, 2016
207
2
18
Texas
If new you will need to get the truck to the dealership and have them programe it. Wont run otherwise. Ben here may also be able to help you on this too as he has the capability of programming BCMs

If the BCM isn't programmed will it still run if I jump the starter?
 

Hambone

Always learning
Jan 24, 2016
572
0
16
Florida
Does anyone have a wiring diagram?
This to me sounds like a grounded wire somewhere
Btw need to get the BCM synced with the rest of the truck
 

LBZ_Baker98

Member
Jul 8, 2016
207
2
18
Texas
Unless someone disabled VATS in the ECM, the truck will not run due to being in theft lock mode.

So I didn't get BCM programmed but I jumped starter and had to drive the truck. Got into town the theft light came on dash and now it starts with the key but the theft light is on
 

LBZ_Baker98

Member
Jul 8, 2016
207
2
18
Texas
Well now truck just quit starting with key again. This thing is going to drive me to drinking!!! After clearing codes it's only throwing p2536 ignition switch accessory possition circuit
 

LBZ_Baker98

Member
Jul 8, 2016
207
2
18
Texas
Truck popped DLIS fuse. Truck will start with key with DLIS fuse removed but security light is on and it idles for about 5 seconds and dies. As soon as you put a fuse in and turn key in DLIS fuse blows. It calls for a 2 amp but it's blowing even a 10 amp fuse is blowing. Thinking ignition wiring but I don't know at this point
 

weazel

Member
Oct 5, 2011
261
0
16
43
Mason, TX
Have y’all replaced the ignition module?
And sounds like it all needs to be programmed to each other so they all are happy with each other.