6L80 Connectivity Issue

Hey all,

TL;DR: I'm not a tuner and don't pretend to fully understand it. My question is, can I flash a custom tuned 6L80 back to factory with only using an HP Tuner or do I have to take this to a GM dealer? If there's any how-to's or guides to doing this with just an HP tuner, please drop the links.

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I was using the Zero Gravity TCM-2650 tuner with a Holley Terminator X, had it tuned and the truck was running/driving okay for several months so I know everything works mechanically. Decided to try out the new Holley 6L80 controller and upgrade to a Terminator X Max + a pro dash with the hope of everything communicating seamlessly.

Updated both Holley products and reloaded my engine tune, engine runs and idles fine. I can put it in drive/reverse and it will go into gear like normal. The issue is, when I turn on the Holley 6l80 tuner and try to tune it for the first time, the handheld thinks for about 5 seconds and then makes buzz sound followed by displaying "Vehicle Communication Error!".

I talked to Holley and Super Chips several times:
- Battery is brand new and voltage is 12.8V.
- All wiring in the hardness is correct (I verified every pin per their wiring diagram, see below).
- They believe the issue is caused from having the transmission tuned previously and that it's now "locked out" from communicating with the Holley tuner. Claim I need to reflash it to factory. I don't really buy this but nothing else is working..

Application:
- 1986 GMC 1500 (C10)
- Engine is a 2001 LQ4 w/ cam, LS3 heads, and truck intake.
- Transmission is from a 2010 Camaro, 6L80e, stock internals.

Holley 6L80 Harness Wiring Diagram:
Attachment 142499

LOL @ holley & "seemless."

srry to hear about your troubles, the pcs setup is a much better product imo. considering you have a holley termi setup id assume you dont have any HPT interface to hop into the TCM with, and see if its actually locked out (doubtful).

it kinda sounds like a CAN issue, there are two CAN wires in the TCM harness; I would quadruple check those wires for continuity.

past that I would either buy a new holley handheld and return the old one or put the PCS setup back in, or continue pestering holley for support

Im having some different but similar issues with the 6L80 i just swapped into a 96 suburban.

First trans had issues, so we got another one, had to return the first transmission to stock before removing, next transmission had a calibration that was not valid with the known OS or whatever they had. So i waited over a week for a tune, now it tunes but i get a P0602. I was hoping to be able to hook HP to it to at least gather more information but its not looking promising

So I think i would try to hook your HP tuners to the OBD port supplied by the Holley harness. I was able to hook to mine with it, make changes, flash etc without a license. If you can't communicate with the HP then maybe the connector isn't clocked right in the transmission or something like that. If its buzzing that might be a little concerning, but either way at least you can verify connectivity with something other than the 6L hand held. Are you able to see any perameters on the Terminator X V3 software? You should at least be able to see basics like gear position etc

Quote:

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Originally Posted by poulina

LOL @ holley & "seemless."

srry to hear about your troubles, the pcs setup is a much better product imo. considering you have a holley termi setup id assume you dont have any HPT interface to hop into the TCM with, and see if its actually locked out (doubtful).

it kinda sounds like a CAN issue, there are two CAN wires in the TCM harness; I would quadruple check those wires for continuity.

past that I would either buy a new holley handheld and return the old one or put the PCS setup back in, or continue pestering holley for support

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I did say "hope" lol

10-4, I'll check those wires again, I did find another forum where a gentleman discussed how his harness was wired incorrectly from Holley which is why I requested the wiring diagram from Holley to verify it. The manual that comes with it shows different wire colors in the CAN connections compared to the wiring diagram. The other forum discussed this too and Holley acknowledges that the documentation provided with the handheld is incorrect.

Quote:

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Originally Posted by dzchey21

So I think i would try to hook your HP tuners to the OBD port supplied by the Holley harness. I was able to hook to mine with it, make changes, flash etc without a license. If you can't communicate with the HP then maybe the connector isn't clocked right in the transmission or something like that. If its buzzing that might be a little concerning, but either way at least you can verify connectivity with something other than the 6L hand held. Are you able to see any perameters on the Terminator X V3 software? You should at least be able to see basics like gear position etc

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Good idea, I don't have an HP Tuner but I'll borrow one and see what I can see. Thanks.

I found that after using HPtuner, I wasn't able to communicate with the transmission directly using the Holley harness but had no issue with previous Zero Gravity harness. Upon further investigation I narrowed it down to a wiring issue and software within the Terminator X Max.

1. Canbus high and low are labeled backwards on the Holley diagram for the OBD2 pins 6 (high) and 14 (low) and 6L80 pins 13 (low) and 14 (high). Other set of canbus pins are correct elsewhere on diagram.
2. Switching from Terminator X to X Max requires software setting "System ICF" > "ECU Configuration" > "ECU Type" > "Terminator X" to be set to "Terminator X Max". This enables the J3 and J4 connectors for the 6L80 to communicate properly.

After this, everything started communicating okay. There is still a bug where I'm unable to tune shift points for 1-2, 2-3, and 3-4. I only have options for 4-5, and 5-6 on the handheld. I've sent my log files to Superchips and am awaiting a call back from their master tech.

Quote:

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Originally Posted by muffinman

I found that after using HPtuner, I wasn't able to communicate with the transmission directly using the Holley harness but had no issue with previous Zero Gravity harness. Upon further investigation I narrowed it down to a wiring issue and software within the Terminator X Max.

1. Canbus high and low are labeled backwards on the Holley diagram for the OBD2 pins 6 (high) and 14 (low) and 6L80 pins 13 (low) and 14 (high). Other set of canbus pins are correct elsewhere on diagram.
2. Switching from Terminator X to X Max requires software setting "System ICF" > "ECU Configuration" > "ECU Type" > "Terminator X" to be set to "Terminator X Max". This enables the J3 and J4 connectors for the 6L80 to communicate properly.

After this, everything started communicating okay. There is still a bug where I'm unable to tune shift points for 1-2, 2-3, and 3-4. I only have options for 4-5, and 5-6 on the handheld. I've sent my log files to Superchips and am awaiting a call back from their master tech.

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Very helpful thread! I?m having the exact same problem as you on a brand new x max setup. I saw the labeling discrepancy you did with the obd2 pin, did switching them work? I cant get into the software yet as I sent the ecu back for a different problem with the 5v ref for the engine sensors but Im trying to track down the problem in the mean time.

Quote:

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Originally Posted by muffinman

I found that after using HPtuner, I wasn't able to communicate with the transmission directly using the Holley harness but had no issue with previous Zero Gravity harness. Upon further investigation I narrowed it down to a wiring issue and software within the Terminator X Max.

1. Canbus high and low are labeled backwards on the Holley diagram for the OBD2 pins 6 (high) and 14 (low) and 6L80 pins 13 (low) and 14 (high). Other set of canbus pins are correct elsewhere on diagram.
2. Switching from Terminator X to X Max requires software setting "System ICF" > "ECU Configuration" > "ECU Type" > "Terminator X" to be set to "Terminator X Max". This enables the J3 and J4 connectors for the 6L80 to communicate properly.

After this, everything started communicating okay. There is still a bug where I'm unable to tune shift points for 1-2, 2-3, and 3-4. I only have options for 4-5, and 5-6 on the handheld. I've sent my log files to Superchips and am awaiting a call back from their master tech.

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Having the same problem did you get your 6l and Holley to act right ?