Lly to Lbz conversion issies.

[onebaddmaxxx]

Ok so this will be lengthy, as I will go into details about my swap so everyone knows what i did. It started off that i purchased a Regular cab long bed 4x4 06 lbz from evan about 2 months ago. The plan for it was to take the engine/trans/ecm and tcm controllers and harness and put them in my 05 truck. The 06 truck had a u0101 loss of comm with tcm. I noticed the truck did not have a wait to start light. Did some digging and found out that if the glowplug module is bad, the tcm sometimes cant communicate and throws the u0101. I had gotten a good used glow plug module while iv been waiting around. I pulled the engine and transmission out a few weeks ago. Studded the engine and built the trans. Thursday I pulled my engine/trans/modules/harness out of my truck and installed the harness from the tcm/ecm/ubec/engine/trans from the 06 truck into my 05. I followed very closely the changes needs from Russ's thread:

http://www.duramaxdiesels.com/forum/showthread.php?t=27198

I have double/triple checked everything. The truck starts with the key, so that tells me the move in the c2 connector from f4 to a5 was correct, I have a check engine light, so my MIL control wire is right also. I have already flashed the ecm, hooked up the 6 speed shifter and wired it in. I have drive and reverse, but still no comm with the tcm. I have swapped my glowplug module into another truck and didnt make a difference, nor did swapping the tcm. The other truck worked as designed when parts were swapped. So I checked my GMLAN +/- at the obd2 port. Getting 60 ohms with key out which is what its supposed to be. Starting to think I have a class 2 communication issue somewhere. Can anyone else think of anything here? I cant get on SI currently as the password is different and cant get ahold of my friend at the dealer as hes away for easter. When i do a class 2 search on the tech2, the tcm is NOT showing up. So not sure what my next step is without some diagrams. Hoping russ or PaCougar will see this.

 

[chrisuns]

Which diagram are you wanting? The tcm connector or the actual schematics?

 

[chrisuns]

MIL Control, Serial Data, Shift Solenoids, PCS2, Torque Signals, and Tow/Haul Switch

 

[chrisuns]

Also, if the gmlan wires you ran from the DLC to c100 aren't twisted, they can pick up noise and cause communication errors.

 

[onebaddmaxxx]

They are twisted. I had the same loss of communication code before I swapped. But I did twist them before I ran them through the firewall.

I would still communicate with the tcm and ecm thru class 2. It's a yellow wire at the tcm....a dark green wire at the ecm. But is there a splice pack they all run to or....?

 

[Cougar281]

Not sure what you're using on the tech 2 to search class2 for the TCM, but I don't think it'll show up there as the TCM doesn't use class 2 for anything diagnostic related. You say you have drive and reverse - is the truck in a condition where it can be driven to see if the TCM is functioning, or if the drive and reverse you have are the hydraulic limp forward and reverse? It sounds like you don't have any communication with the TCM at all. I assume you have a CANDi module and are building it as an 06 or 07?

Have you made sure the TCM is getting power at pin 10? It sounds like the TCM isn't powering up.

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[onebaddmaxxx]

Not sure what you're using on the tech 2 to search class2 for the TCM, but I don't think it'll show up there as the TCM doesn't use class 2 for anything diagnostic related. You say you have drive and reverse - is the truck in a condition where it can be driven to see if the TCM is functioning, or if the drive and reverse you have are the hydraulic limp forward and reverse? It sounds like you don't have any communication with the TCM at all. I assume you have a CANDi module and are building it as an 06 or 07?

Have you made sure the TCM is getting power at pin 10? It sounds like the TCM isn't powering up.

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Have candi module, I built the truck as a 2006 2500 6.6 When its asks for engine/trans etc, chassis, body in the beginning the 4th option is class 2 circuit. Then it does an auto detect on everything there. I confirmed with another 06 truck at the shop, and tcm does show up on his when I do it.
pin 9 and 69 for grounds, check. and pins 10 and 63 have power.

 

[onebaddmaxxx]

Not sure what you're using on the tech 2 to search class2 for the TCM, but I don't think it'll show up there as the TCM doesn't use class 2 for anything diagnostic related. You say you have drive and reverse - is the truck in a condition where it can be driven to see if the TCM is functioning, or if the drive and reverse you have are the hydraulic limp forward and reverse? It sounds like you don't have any communication with the TCM at all. I assume you have a CANDi module and are building it as an 06 or 07?

Have you made sure the TCM is getting power at pin 10? It sounds like the TCM isn't powering up.

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In all of your posts relating to the swap, you talk about switching F4 to A5. What is supplying power to A5? The pinout for the c100 connector for 2005 shows A4-A6 being unused. Found a few people saying switch it to A8. Which is battery positive voltage.

 

[Cougar281]

Is it possible you have a bad TCM? Have you tried another? You say you flashed the ECM - i assume with a V2?

You say the 06 truck had a loss of comms with TCM code, so I would suspect your problem doesnt lie with your swap.

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[onebaddmaxxx]

Is it possible you have a bad TCM? Have you tried another? You say you flashed the ECM - i assume with a V2?

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Check my question prior to your last post please.

Yes used my v2 to flash the tunes. I put my TCM in another truck and it drove fine, and put that tcm in mine and still didnt change anything.

I also turned VATS off in the ecm tune. I also checked that the ecm tune did go in properly, as i put a dsp switch in and checked through the scan tool, and my voltages show properly as I turn the switch.

In my experience, an LBZ truck wont start with the tcm unplugged. My truck does start. If that matters.

I am going to try swapping the F4 wire i put in A5, to A8 in the morning, and ohm the class 2 wire from the tcm connector, to the obd plug.

 

[Cougar281]

In all of your posts relating to the swap, you talk about switching F4 to A5. What is supplying power to A5? The pinout for the c100 connector for 2005 shows A4-A6 being unused. Found a few people saying switch it to A8. Which is battery positive voltage.

C100 does not have F4 or A5. It's a 16 cavity connector labeled A through S.

The connector with the orange wires in F4 that I had to move to A5 are in C1 of the underhood fuse block.

According to the info I have, that pin that was originally in F4 for the 2006 truck goes to pins 10 and 70 on the TCM. Pin 63 should only have power with the ignition on.

According to the info I have, there is a splice for each of the GMLAN wires in the harness about 9cm from the ECM connector. If there is a problem with the GMLAN wires to the TCM, you might still be able to communicate with the ECM, but the TCM and GPCM would be cut off. Have you checked for continuity between pin 6 on the TCM & C2-57 on the ECM, and pin 27 on the TCM & C2-44 on the ECM?

Again, you said the 06 had a loss of comms code and didn't seem to have a wait to start light, so since you have power to the TCM, its sounding like you may have a data line issue that existed before your swap.

And the truck should start without the TCM. If memory serves, mine does.


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[onebaddmaxxx]

C100 does not have F4 or A5. It's a 16 cavity connector labeled A through S.

The connector with the orange wires in F4 that I had to move to A5 are in C1 of the underhood fuse block.

According to the info I have, that pin that was originally in F4 for the 2006 truck goes to pins 10 and 70 on the TCM. Pin 63 should only have power with the ignition on.

According to the info I have, there is a splice for each of the GMLAN wires in the harness about 9cm from the ECM connector. If there is a problem with the GMLAN wires to the TCM, you might still be able to communicate with the ECM, but the TCM and GPCM would be cut off. Have you checked for continuity between pin 6 on the TCM & C2-57 on the ECM, and pin 27 on the TCM & C2-44 on the ECM?

Again, you said the 06 had a loss of comms code and didn't seem to have a wait to start light, so since you have power to the TCM, its sounding like you may have a data line issue that existed before your swap.

And the truck should start without the TCM. If memory serves, mine does.


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I meant c2 Connector when I was talking about f4 To a5. Sorry it's been a long weekend.

 

[onebaddmaxxx]

So in all the threads, showing f4 to a5 in the c2 connector, it needs to go to a8 instead. Swapped that this morning and everything is good. Still weird how I had all my powers and grounds when tested at tcm plug. Thanks for the help!

 

[dmax Gordy]

Does anybody no if I have to switch c2 orange wires for tcm power even if im using the lbz fuse block instead of the lly?