4L80E speed sensors
4L80E speed sensors I replaced the two speed sensors on the DS of my 4l80e and now it doesn't want to shift. While logging the mph stays at zero. Are there different speed sensors for the 4L80 trans and if so can you please share the part number. I bought mine of fleebay and they were made by ACdelco. The trans came out of a 1995 Van. It shifted just fine before the change but I wanted new sensors since I had the trans redone recently. And no, I do not have the old ones. 
I would like to add that I have a Dakota Digital instrument cluster and it gets its speedo function off of the VSS wire and it was working. Soooooo I may have something else going on. Any suggestions?
I would like to add that I have a Dakota Digital instrument cluster and it gets its speedo function off of the VSS wire and it was working. Soooooo I may have something else going on. Any suggestions?
Last edited by Monte4ever; May 7, 2014 at 03:33 PM.
Everything worked before but last year while logging i noticed that the mph kind of fluttered off and on but it was shifting fine, however now it stays on zero. I checked the VS connector wires to the C2 connector pin 20 and 21. Everything checked out fine. Im trying to contact hptuners and see if they can look over my segment swap. Maybe something got "lost" within the tune while I was making changes over the winter.
Last edited by Monte4ever; May 9, 2014 at 10:07 AM.
Trending Topics
Here's where I'm at with this. As mentioned above I changed the internal wiring harness. Just to make sure I did not leave anything unplugged I dropped the pan and everything was plugged in. I got the harness off fleabay and the listing states that it was for years 1994 thru 2003. Well guess what, Rock Auto says this part (24241218) is for years 1996 thru 2003. My trans model year is 1995. Looks like I need part# 24200161. Buy the way, the trans came out of a P30 Van (to the best of my knowledge).
Last edited by Monte4ever; May 18, 2014 at 05:41 PM.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?
Pouria Savadkouei
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo Well after checking my wiring and not finding anything unusual I logged Vehicle Speed (again) and Input Shaft Speed. Input shaft speed registered but VS did not. My Speedo works (Dakota Digital uses the VSS) and the sensors are new. I also got a new segment swap from HPtuners which did not fix the issue. I'm at a lost. I may just change out the PCM. Man I was trying not to dump MORE money into this thing. Haven't had a good season driving it yet. 
Last edited by Monte4ever; May 21, 2014 at 11:44 AM.
The VSS is a required input for the PCM to determine when to shift.
Lack of VSS signal is your problem.
It's a simple circuit, 2 wires.
If the trans has a reluctor ring inside, the sensor is there (they RARELY fail), and the wiring is good, you have a PCM issue.
However, be sure your Dakota dash isn't interfering with the signal. I would take it out of the circuit until you sort it out.
Lack of VSS signal is your problem.
It's a simple circuit, 2 wires.
If the trans has a reluctor ring inside, the sensor is there (they RARELY fail), and the wiring is good, you have a PCM issue.
However, be sure your Dakota dash isn't interfering with the signal. I would take it out of the circuit until you sort it out.
PCM's rarely fail too, as least on GM stuff.
I would look at the wiring from the VSS to the PCM closely. Take the Dakota digital out of the circuit, be sure the wires have good continuity, and check across both wires with a voltmeter with the driveshaft static and with it turning at low speed.
I would look at the wiring from the VSS to the PCM closely. Take the Dakota digital out of the circuit, be sure the wires have good continuity, and check across both wires with a voltmeter with the driveshaft static and with it turning at low speed.
Jake you were right on the money along with some others. It was the Dakota Digital Speedo killing the VSS signal. It worked last year but for some reason it decided not to work this time.
