4L60e to 4L80e Swap - No Speedometer

[Trent1080]

Hey Everyone,

I'm in the last step of a 4l80e swap into a 2002 Camaro. For whatever reason I cant get the speedometer to register. It was working prior to the swap. The tach and everything else works. I'm really baffled as to what I'm missing. I've done the following to diagnose. Between each change I have the car lifted and am running it in gear to see if I register anything on the speedo.

• Unplugged new ISS connector and verified continuity to ECU (pins 22 and 23)
• This harness was added for the swap
• Logged Input shaft RPM via HPTuners
• Registers when in gear and wheels are moving, which confirms the ISS is good. When in gear and brakes are applied, it registers 0
• Logged "VSS Fault" and "VSS A Fault"
• no errors
• Logged "Vehicle Speed (SAE)
• Always 0 mph
• Verified there is nothing speed related on the main trans connector wiring per the diagram
• Loaded original software pre-swap and no change
• has been reverted back to segment swapped tune
• Double checked current tune (segment swapped) and re-wrote to PCM - no change
• Tune attached below

Everything I've read/seen says you use the ISS on the 4l80e but not the OSS. The PCM is supposed to take the ISS input and convert that to MPH which is displayed on the speedo. What am I missing? I used BlueCat software to setup the speedo and trans settings.

Stock OS (PD COPY) - Engine Engine Diag Trans Trans Diag Fuel Sys System Speedo.hpt2002 Camaro 2.16.2020.hpt

"Stock OS...hpt" is the current file.

"2002 Camaro...hpt" is the file before the 4l80e swap.

Thanks for any comments.

[Frost]

You plug the OEM VSS plug into the OSS plug on the 80. If you are using an 80 segment, you need to run the ISS back to the ECM and plug it up to the trans. If you are running the 80 on a 60 segment (depends on adapter / wiring type), then you fully ignore the ISS on the 80.

[Trent1080]

Thanks Frost. I did eventually figure that out. Funny enough in all the guides I read, the adapter cable instructions from BP Automotive, and a few Youtube videos. The existing sensor cable is never mentioned or shown. What you've said is 100% correct. I thought I was going insane, but I double checked and that is never specifically mentioned.

As soon as I plugged it in I got my speedometer back.