Gas gauge backwards after Flash

**DaleSlides** · 04-28-2021

2003 Silverado, 4x4, LM7. Original OS 12579405, written OS is 12587603 (both 1mb).

Only change I made to the replacement file was disabling torque management. Truck runs great, however I noticed my Fuel gauge reads backwards (Empty reads full, Full reads empty). There isn't an XDF for my original OS, which is why I moved to the new OS (The file written to the truck is from an 04 LM7 4x4).

There is a Fuel gauge table in the new OS that sends PWM values to what I am assuming is the stepper motor in the cluster, and I would assume reversing the values here would fix my problem.. however I wanted some input before making the move.

**2xls1** · 04-29-2021

Looking at 03 and 04 Silverado files with HP Tuners there are 2 tables in the Fuel System section that are flipped between the 2 year calibrations. They are labeled Primary Volume and Primary Volume Gauge. Here is the data from the 03 Calibration that you can copy into the 2 tables in the 04 File that should fix the gauge.

**DaleSlides** · 05-01-2021

Thanks for the input buddy, I was able to look at the XLS file you attached and see the values, however I am unable to see the same table on my setup since I'm using LS droid and Tunerpro.

I tried reversing the values in the table I mentioned in the first post, however the file failed to write (twice), and I was forced to recover the PCM using my previous Bin.

I'll keep digging into this, hopefully someone has resolved it.

**2xls1** · 05-01-2021

Those tables are probably not defined in the XDF you are using. Post the bin file from your 03 and the bin file from the 04 you are using and I can insert the data into the 04 file and save it and put it back up here for you to use. I have lots of editing tools. That way if there is a difference in fuel tank sizes between the 2 it will have the correct data for your 03 truck. Many times there can be slight differences in fuel tank sizes in the trucks and I can copy every table relevant to that into the 04 file. If you don't have a bin for the 03 then post the VIN and I can figure it out.

**DaleSlides** · 05-02-2021

Originally Posted by 2xls1

Those tables are probably not defined in the XDF you are using. Post the bin file from your 03 and the bin file from the 04 you are using and I can insert the data into the 04 file and save it and put it back up here for you to use. I have lots of editing tools. That way if there is a difference in fuel tank sizes between the 2 it will have the correct data for your 03 truck. Many times there can be slight differences in fuel tank sizes in the trucks and I can copy every table relevant to that into the 04 file. If you don't have a bin for the 03 then post the VIN and I can figure it out.

The Bin starting with 161937 is the factory file read from my PCM, the other is the 04 file with torque management deleted.

Thanks for your help man

**2xls1** · 05-02-2021

The only torque management setting I see changed is Max Tq changed to 639. That does not disable torque management. If you want me to I can disable it correctly if you want.

**2xls1** · 05-02-2021

Here is the 04 file with all Torque Management Disabled, the 03 Fuel Gauge data, and I changed the Injector data to what is correct for a 03. 03s use a return fuel system with a regulator on the rail and 04s use a dead head system with no return and the regulator in the tank. There is a difference in the Fuel Injector tables between the two different systems. Let me know if this fixes the gauge issue.

**DaleSlides** · 05-02-2021

Originally Posted by 2xls1

Here is the 04 file with all Torque Management Disabled, the 03 Fuel Gauge data, and I changed the Injector data to what is correct for a 03. 03s use a return fuel system with a regulator on the rail and 04s use a dead head system with no return and the regulator in the tank. There is a difference in the Fuel Injector tables between the two different systems. Let me know if this fixes the gauge issue.

Thanks a ton man, evidently I need to do a lot more reading/studying on the LS XDFs/OSs.. they're layout and such. I will be flashing it in just a minute, I'll let you know how it goes. I'd like to do some reading on the tools you're using, do you mind pointing me in the right direction? Thanks again!

**DaleSlides** · 05-02-2021

That was it, gas gauge is reading properly now and the truck drives great. You're a life saver, I really appreciate it.

**2xls1** · 05-02-2021

Originally Posted by DaleSlides

I'd like to do some reading on the tools you're using, do you mind pointing me in the right direction? Thanks again!

They are commercial tools. HP Tuners and Tunercat OBD2 with lots of licenses bought.

While I think it's great that people are trying to develop free tuning solutions what I see is a lot of people running the wrong OS for their vehicles due to lack of XDF files and not knowing what is wrong with doing that. For example thinking any blue/green OS is fine to use in any vehicle that came with a blue/green box. That is not always the case.

**Bmurph2000** · 08-01-2021

Im having this exact issue and was wondering if you'd possibly be able to correct the injector data to an 03 with the return, and also the fuel gauge data to what it needs to be in order to work with a 2003 truck.Im just getting started with tunerpro and dont know my way around it yet, so your help would be greatly appreciated. The bin im using is below

**2xls1** · 08-02-2021

Read the original PCM in the 03 and post it here so I can see what other differences there might be.

**trlrider** · 08-02-2021

Originally Posted by 2xls1

For example thinking any blue/green OS is fine to use in any vehicle that came with a blue/green box. That is not always the case.

Agreed! Recently cloned a pcm in a '05 Workhorse P42 with a 4.8. The A/C was not working prior to the cloning, so I did not think about it.
Oddly since the replacement pcm fixed a half dozen other issues the owner was having, he asked if we could fix the a/c!
My boss started the process thinking it was something like a low freon, bad pressure switch etc.! I got freed up from the other project I had and started digging and found the a/c compressor clutch relay was not getting a signal from the pcm.
Found out my boss had probed it and shot 12 volts where there should have been a ground signal, and promptly burned something up in the replacement pcm.
Anyway, found out in the research that the service number I originally used did not have the output for the a/c compressor clutch.
Went to the house, pulled out another spare that documentation showed did have the signal, and cloned it.
Put it in and replaced the fuse my boss fried and the a/c compressor started working.
Oddly, the 1st replacement pcm came out of a 2005 Suburban. Thus I do not understand why that service number did not have the compressor clutch signal at that pin!
Anyway, yes not all blue/greens are created equal.

**2xls1** · 08-02-2021

Originally Posted by trlrider

Agreed! Recently cloned a pcm in a '05 Workhorse P42 with a 4.8. The A/C was not working prior to the cloning, so I did not think about it.
Oddly since the replacement pcm fixed a half dozen other issues the owner was having, he asked if we could fix the a/c!
My boss started the process thinking it was something like a low freon, bad pressure switch etc.! I got freed up from the other project I had and started digging and found the a/c compressor clutch relay was not getting a signal from the pcm.
Found out my boss had probed it and shot 12 volts where there should have been a ground signal, and promptly burned something up in the replacement pcm.
Anyway, found out in the research that the service number I originally used did not have the output for the a/c compressor clutch.
Went to the house, pulled out another spare that documentation showed did have the signal, and cloned it.
Put it in and replaced the fuse my boss fried and the a/c compressor started working.
Oddly, the 1st replacement pcm came out of a 2005 Suburban. Thus I do not understand why that service number did not have the compressor clutch signal at that pin!
Anyway, yes not all blue/greens are created equal.

You are talking about hardware. I'm talking about using the 04 OS in vehicles that use a blue/green box that are not MY 04. It's the inability to see what that other MY OS is using vs what the 04 OS is using because of lack of XDFs.

**Bmurph2000** · 08-02-2021

thanks for the help. The original bin from the 03 is below. Im also having trouble disabling torque management, not sure if you could help with that or not. Id like to keep torque management on for the shifts but I cant get it to do brake stands for the life of me and it also feels sluggish off the line like its cutting power, just all around making it no fun. Tia