The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > General Truck Forums > Engine & Drivetrain > LSx Swaps

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 09-03-2019, 09:55 AM   #1
coacharmstrong1990
Registered User
 
Join Date: Aug 2018
Location: Ashland Kentucky
Posts: 27
New Wiring Harness-No shift

I just installed a new BP-Automotive Wiring Harness and the quality and ease of installation is great. My engine was running like crap with the homemade harness but is running great with he new harness. However my transmission has stopped shifting. With my janky homemade harness it would shift but now it will not. could this be TCC lock up issue? maybe i have the pole switched in the brake switch? IIRC the purple wire is going to the 3rd post from the top and the 12v constant to the bottom post?

maybe a fluid level issue?

thoughts, ideas?
coacharmstrong1990 is offline   Reply With Quote
Old 09-03-2019, 11:32 AM   #2
87chevy.com
BMW & ASE Master Certified
 
87chevy.com's Avatar
 
Join Date: Feb 2004
Location: Houston, Texas
Posts: 1,266
Re: New Wiring Harness-No shift

Tcc would not cause that. Checkyour basics first. Fluid and fuse.
Top post and bottom post? No idea what your talking about. When talking about wires and connector. e specific what connector and what pin number
__________________
1987 Silverado - L83 5.3 w/ 6L80e ,A/C,P/W,P/L,TILT, HID projectors, Wilwood C-10 Pro Spindles w/ 2018 silverado front brakes & C-5 Corvette Rear Disc Brakes
1999 BMW 528i - 5.7 LS1 w/ 4l60e, Ford 8.8 IRS w31 spline posi & FX-r projector retrofit

New project: 2006 BMW x5 6cyl AWD to L83 6l80e 4wd to 2WD / RWD

A poor man buy's it twice

finally got my domain name back, 87chevy.com.... site rework in progress
87chevy.com is offline   Reply With Quote
Old 09-03-2019, 12:25 PM   #3
BigBird05
Registered User
 
Join Date: Aug 2019
Location: Cheraw
Posts: 1,300
Re: New Wiring Harness-No shift

You didn't give any details about what type of truck you are working on. You need to tell us everything about the truck if you what us to try and help.
BigBird05 is offline   Reply With Quote
Old 09-04-2019, 10:57 AM   #4
coacharmstrong1990
Registered User
 
Join Date: Aug 2018
Location: Ashland Kentucky
Posts: 27
Re: New Wiring Harness-No shift

1968 C10- Gen III 5.3 cammed and 4L80e

got it fixed the main plug was plugged in upside down
coacharmstrong1990 is offline   Reply With Quote
Old 09-04-2019, 08:34 PM   #5
Wildkarde
Registered User
 
Join Date: Mar 2018
Location: Ardmore
Posts: 100
Re: New Wiring Harness-No shift

i didnt think that was possible, at least you got it fixed.
Wildkarde is offline   Reply With Quote
Old 09-04-2019, 10:21 PM   #6
YoungPup1977
Account Suspended
 
Join Date: Jun 2015
Location: No longer here
Posts: 1,000
Re: New Wiring Harness-No shift

Quote:
Originally Posted by coacharmstrong1990 View Post
1968 C10- Gen III 5.3 cammed and 4L80e

got it fixed the main plug was plugged in upside down
Can you explain what the main plug is, just wanting to know if I ever have this issue I will know what to do. Can you take a pic of this as well. Thanks
YoungPup1977 is offline   Reply With Quote
Old 09-04-2019, 10:29 PM   #7
ls1nova71
Registered User
 
ls1nova71's Avatar
 
Join Date: Dec 2009
Location: Independence Mo
Posts: 4,119
Re: New Wiring Harness-No shift

Quote:
Originally Posted by YoungPup1977 View Post
Can you explain what the main plug is, just wanting to know if I ever have this issue I will know what to do. Can you take a pic of this as well. Thanks
Most likely he's talking about the big round plug that plugs into the transmission itself. It has small detents to keep it from being plugged in backwards, but they are small enough that you can do it. Seen it done a couple of times.
__________________
My '72 short bed build. http://www.ls1tech.com/forums/conver...6-0-4l80e.html

5.3 swap into my RUSTY '71 C10
http://ls1tech.com/forums/conversion...71-c-10-a.html
ls1nova71 is offline   Reply With Quote
Old 09-04-2019, 10:55 PM   #8
YoungPup1977
Account Suspended
 
Join Date: Jun 2015
Location: No longer here
Posts: 1,000
Re: New Wiring Harness-No shift

What year of 4L80E is it ? early years ?

Hey LS1 can you answer this too ?
Attached Images
 

Last edited by YoungPup1977; 09-06-2019 at 01:25 PM.
YoungPup1977 is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 01:31 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com