Which wire for tach.signal...

[FlyBryViper]

need to connect a shift light to the tach. signal wire. Which wire do you recommend and WHERE IS IT???????????

 

[Steve-Indy]

I'm GUESSING that you have a 2001...try the gray/light blue wire off of pin 31 on C3 module of powertrain control module for the tach signal...or, some use the signal wire at the back of tach.

 

[Qualitywires.com]

What wire is that steve? What does it go to?

I thought you had to get some type of tach adapter to make the signal work.

 

[Steve-Indy]

It goes out of PCM C3 pin 31 to the back of the Tach as noted above...some pick up this wire at the C3 pin, while others grab it at the back of the Tach.

 

[Achilles99]

need to connect a shift light to the tach. signal wire. Which wire do you recommend and WHERE IS IT???????????

I know you ordered one of the Raptor shiftlights after posting this question, so I'm assuming you know to use one of the ignition coil wires on the PCM, right ?

 

[Steve-Indy]

Sounds as though the signal from C3 pin 31 (officially listed in the factory manuals as "tachometer signal") is NOT READABLE by the Raptor brand...follow Achilles99's directions to the coil pins in PCM C1 and it should work.

 

[J DAWG]

I used pin#3 on C1, the red with yellow trace wire. It is an ignition coil driver.

 

[Steve-Indy]

Looks like others are finding that with the Raptor unit, one MUST use one of the C1 module "coil" pins...and not waste time with the C3 pin 31 "tach signal" that works with some other makes.

See post by Joseph Dell:

http://vca2.viperclub.org/forums/showthreaded.php?Cat=&Board=UBB14&Number=504072&page=1&view=collapsed&sb=5&o=&vc=1

 

[REDSLED]

I plugged into the seat rail. The same one that measures 50 RWHP for headers & smooth tubes and 60 RWHP for switching gears to 3.55's

 

[Joseph Dell]

Y'all crack me up.

Red with yellow stripe on C1 is a good choice. And easy to find too. Do this for the RAPTOR shift light. Don't do C3 pin 31 with the Raptop or you'll bang your head against the wall like I did. Even with the 2.5PPR setting, the raptor didn't like it.

JD

 

[FlyBryViper]

Thanks guys, I got it right with the C1, pin #3, red/yellow wire. I really appreciate everyone'e help.