ls1_Incognito

iTrader: (2)

QUESTION RESOLVED

Hey guys,
My 2001 LS1 swap into a 1989 RX7 is almost running except for one detail:

There are two wires coming from the VSS ( Vehicle Speed Sensor, Driver side T56 tranny). Can some one identify what PCM pins these wires go to. Here are the details I have:

- VSS Wire from the PCM RED 50
- VSS Low signal Wire from the PCM RED 20
- VSS High Signal Wire from the PCM RED 21

ya.... so I'm stumped... Please help, been searching like crazy with no luck

Schitzo

iTrader: (6)

your details are correct.
http://www.ls2.com/boggs/torques/2001pinpcm.htm

ls1_Incognito

iTrader: (2)

Yes,
I have two wires from the sensor that need to be assigned to 1 of 3 spots on the PCM..... Which spots do they go?

ls1_Incognito

iTrader: (2)

OK... so here is a pic of the OEM VSS plug:


So the colors are Purple and yellow.....

RED 20 -- VSS Low signal -- has LT GRN/BLK wires

RED 21 -- VSS High signal -- has PPL/WHT wires

RED 50 -- VSS signal -- has DK GRN/WHT wires

.....damn it...... thought I had this solved

ls1_Incognito

iTrader: (2)

So I know Purple on plug to Purple on the PCM is GOOD !!!!! Now I just need to know if the yellow plug wire gos to PCM RED pin 20 or RED pin 50.

Does anyone have a LS! wire harness off the vehicle?

If so; a quick continuity test will answer my question....... Pllleeeeaaassseee

shoemike

iTrader: (25)

C2 (red) pin 50 goes to the IPC and the BCM.

ls1_Incognito

iTrader: (2)

So.... process of elimination means RED pin 20 is my wire.

OK, I'm going with it!! BIG thanks!!!

Chris Julian

Guys,

I'm working this problem from the other end. I have an LS7 crate engine in a Kit Car and have an engine harness with the Yellow and Purple wires that should feed a VSS sensor. My question is: will the yellow and purple wires work with an aftermarket sensor? I beleive the yellow wire is the voltage for the sensor and the purple wire is the "trigger" for the ECM. Any thoughts? This is driving me nuts!

Thanks, Chris

Al3e925

Did you ever figure it out? Ive got an nv3500 and trying to route the vss wires purp n yellow/ green to my pcm or to the speedo

jwesley4152

Did that work for you? If not, Please share what did work.. Thank You

gagliano7

Pin 20 and 21 are the input from the trans to the pcm. Pin 50 goes to the speedo. I have it setup on my 1992 pickup swap. You can make adjustments with pcm to get your speedo to read correctly.

oange ss

iTrader: (50)

no "voltage" or "trigger" in the VSS system. The speed sensor is an AC signal generator....wiring has nothing to with operation of the system, the question is will the aftermarket sensor provide the correct signal to the pcm

Grendel

iTrader: (27)

Does it make a difference if it's one pin or the other?