4L80E problems

[TagAllen]

94/95 used a different pcm then earlier years. So if you brought the pcm and harness from a 92 and put it in a 94 the white box you already have may not be compatible with your 92 computer.

Have never had anything to do with these guys but here is a interesting place related to what I am talking about.

https://www.udmodule.com/drac/

 

[94_chevy]

94/95 used a different pcm then earlier years. So if you brought the pcm and harness from a 92 and put it in a 94 the white box you already have may not be compatible with your 92 computer.

Have never had anything to do with these guys but here is a interesting place related to what I am talking about.

https://www.udmodule.com/drac/

So do you recommend getting a vssb from a 92? Or is there a way to bypass it?

 

[TagAllen]

I think if you can get a cheap/free one its worth a try.

 

[94_chevy]

I think if you can get a cheap/free one its worth a try.

Junkyard trip it is I’ll see when I can go and get a couple. In the mean time I’ll be checking everything else that everyone brought up to check

 

[PEIslander]

The 4l80E requires full 12V all the time. The PCM controls the solenoids by grounding each one when needed. You can buy full standalone controllers for the 4l80e but they are pricey.

 

[94_chevy]

At least .5 at idle

Checked volts at tps. .5 on blue wire and 6.5 on grey wire while idling

 

[94_chevy]

It makes way more sense to call it "transmission." Lol. But it still could be something along those lines with the same wire... I'm assuming alot of thing are the same with wiring from 4l60e to 4l80e... so Pin E should be the same. Pin E on the big round plug at the tranny is the only positive feed, comes from ignition to fuse then to tranny. It should read the exact same voltage as the battery. Stick an appropriate sized drill bit inside for testing. Pin E is also a pink wire.

Al

Transmission is receiving 12volts constantly

 

[94_chevy]

I think if you can get a cheap/free one its worth a try.

Forgot to mention when it had the 4l60e before I swapped it. It had the iss wire running from the trans to the cluster area and then to the vssb. With the 4l80e the iss wire runs directly into the pcm

 

[TagAllen]

Your 4l60 had a iss? Do you mean VSS?

 

[94_chevy]

Your 4l60 had a iss? Do you mean VSS?

Yess vss. Sorry couldn’t remember