Diablo to HP Tuners Conversion Issue

Hey all,

I recently swapped my CMR tune to HP tuners and after doing so am getting a "P0731 - Gear 1 Incorrect Ratio" CEL which is throwing to car into Limp Mode. I will admit that I didn't realize I had to jump into the VCM scanner to adjust the Tire Size and Gear Ratio initially but after making those appropriate changes my car still throws the same CEL.

Has anyone ran into a similar issue? I'm kind of at a loss here. Any way that HP Tuners didn't fully read the CMR Tune? Could this have something to do with NAG1s needing to be "re-initialized"?

Any ideas would be greatly appreciated,
Bruggy

So I swapped TCMs with no luck. Still get the same "Incorrect Ratio" errors. I was however able to successfully revert back to my CMR tune using the Trinity and all is working again. This leads me to believe that the issue doesn't reside within the TCM but rather HP Tuners is having trouble setting the Axle ratio value which is stored on the PCM?? I'm going to try and convert over again but will be sure and set the Axle ratio before writing the HP Tuners base tune.

Whelp, looks like this is a known issue with HP Tuners..

https://forum.hptuners.com/showthrea...ge-Not-Working

Use your diablo use it to set to your proper gear ratio. If you have two TCMs... plug the one you want to use and change the ratio in the quick settings on your diablo. Then swap it for another TCM and change the gear ratio in quick settings again, then restore stock tune and the diablo will be unmarried and you will have one TCM with correct gear ratio.

Yep, I'm currently using the DS to change the axel ratio and all it now working as it should. Still bothers me why this is an issue though. I've talked with a very reputable tuner about this and he said that he's never had a problem on any of the cars he's worked on over the years. I'm assuming it must be something with HP not recognizing and/or not being able to override where DS makes the Axel setting. I say this because even after I made the ratio change to 3.73 with DS, HP still reads a 3.06 gear when viewing through the VCM Scanner.

I had to do the same thing. Had to set the ratio with DS to make it work. No issue for me as I still have the trinity in my car for on the fly logging and to keep an eye on things.

Are you using a bypass cable by any chance? A member here found on his jeep that the HP tuners bypass was preventing the ABS from re-initializing. Also, have you looked into getting AlfaOBD. It does not work with the HP tuner interface and needs an aftermarket one (like OBDlink MX). It is software for FCA vehicles that allows you to change BCM configuration...really compliments HP tuners IMO.

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Originally Posted by Homer

Are you using a bypass cable by any chance? A member here found on his jeep that the HP tuners bypass was preventing the ABS from re-initializing. Also, have you looked into getting AlfaOBD. It does not work with the HP tuner interface and needs an aftermarket one (like OBDlink MX). It is software for FCA vehicles that allows you to change BCM configuration...really compliments HP tuners IMO.

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AlfaOBD is amazing but does not have the ability to change gear ratio for the Nag trans as it is stored in the TCM. It works great for newer vehicles that have RFE trans and are BCM/TIPM based as gear ratio is stored in the BCM. It does not work for the ZF trans either as the gear ratio is stored in the TCM as well which is built into the valve body.

AlfaOBd also does a lot more than allow you to change the BCM config. You connect to many different modules and run many different Chrysler misc functions. Such as program fobs, Another application that is a bit more user friendly that uses the same OBD interfaces is AppCar Diag.

I have an open case with HP tuners regarding the gear ratio change not working on all EGS52/53 based TCMs, so hopefully their engineers figure it out. If DS can do it HP should as well IMO.

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Originally Posted by Bullet300

I had to do the same thing. Had to set the ratio with DS to make it work. No issue for me as I still have the trinity in my car for on the fly logging and to keep an eye on things.

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Yeah, I'd like to ditch the DS entirely but that doesn't appear to be an option with everything that I've tried. At this point I feel I've already exerted too much effort towards this issue. :p

Quote:

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Originally Posted by Homer

Are you using a bypass cable by any chance? A member here found on his jeep that the HP tuners bypass was preventing the ABS from re-initializing. Also, have you looked into getting AlfaOBD. It does not work with the HP tuner interface and needs an aftermarket one (like OBDlink MX). It is software for FCA vehicles that allows you to change BCM configuration...really compliments HP tuners IMO.

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Nah, not using a bypass cable. Car is a 2013. I have looked into the AlfaOBD tuner but as ICanuck said I don't think that it'll work for my application. Thanks for the suggestion though

Quote:

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Originally Posted by iCanuck

I have an open case with HP tuners regarding the gear ratio change not working on all EGS52/53 based TCMs, so hopefully their engineers figure it out. If DS can do it HP should as well IMO.

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Keep me posted. If I can be of any use trouble shooting let me know.

Quote:

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Originally Posted by iCanuck

AlfaOBD is amazing but does not have the ability to change gear ratio for the Nag trans as it is stored in the TCM. It works great for newer vehicles that have RFE trans and are BCM/TIPM based as gear ratio is stored in the BCM. It does not work for the ZF trans either as the gear ratio is stored in the TCM as well which is built into the valve body.

AlfaOBd also does a lot more than allow you to change the BCM config. You connect to many different modules and run many different Chrysler misc functions. Such as program fobs, Another application that is a bit more user friendly that uses the same OBD interfaces is AppCar Diag.

I have an open case with HP tuners regarding the gear ratio change not working on all EGS52/53 based TCMs, so hopefully their engineers figure it out. If DS can do it HP should as well IMO.

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Ah, should have read more carefully OP did mention the older controller.

I must say for $50 software I am still surprised what it can do. Recently messed with changing odometer reading (bumped up by 6 miles then reset to original reading...was using a can bus shield to log the bus) on a 2015 challenger to help out a member in another forum who was trying to hack the IP cluster for a project car of his. I thought no way will it work but it does. Kind of scary because I can see people misuse this capability.