Calgary Jeep Association

4x4 Related Groups => Tech Talk => Topic started by: Fredduck on May 15, 2008, 11:15:06 PM

Title: VSS
Post by: Fredduck on May 15, 2008, 11:15:06 PM

Here's a question for the brain powers that be.
Can I hook up the VSS (vehicle speed sensor) wire to an electronic speedo without going through a computer?
I'm sure the speedo will have to be aftermarket. I was looking at isspro gauges.

Any help would be freaking frantastic.

Title: Re: VSS
Post by: Bnine on May 15, 2008, 11:34:58 PM

Not sure Fred. I do know you can attach VSS to your stock system via an upgraded pigtail from a 98 TJ. Plug and play.

I have the part number at work if you need it. Otherwise, nothing to add regarding the aftermarket stuff.

Title: Re: VSS
Post by: Fredduck on May 16, 2008, 06:43:00 AM

Thanks Bill, I somehow knew you might have the answer ;D
I completely removed the '88 computer system so I have to feed the speedo from the transfercase.
The T case is a 241-C and should produce 40 pulses per rotation
I kind of want to keep the look of the stock YJ dash. Is the TJ speedo 3.5 round, i can't remember?
I might just have to use a handheld GPS for a speedo.

Title: Re: VSS
Post by: BlackYJ on May 16, 2008, 07:17:12 AM

Quote from: Fredduck on May 16, 2008, 06:43:00 AM

Thanks Bill, I somehow knew you might have the answer ;D
I completely removed the '88 computer system so I have to feed the speedo from the transfercase.
The T case is a 241-C and should produce 40 pulses per rotation
I kind of want to keep the look of the stock YJ dash. Is the TJ speedo 3.5 round, i can't remember?
I might just have to use a handheld GPS for a speedo.

If you are going into a '88 you might have some problems because i believe it was still cable instead of an electronic sensor like the newer ones

Title: Re: VSS
Post by: 4PLAYZJ on May 16, 2008, 08:02:25 AM

If it has an electronic speedometer you will not be able to hookup the VSS directly to the cluster and have it work.  The VSS output is an analogue wavform that is only millivolts.  If your speedo is cable driven check out this:

http://www.hawksthirdgenparts.com/index.asp?PageAction=VIEWPROD&ProdID=906 (http://www.hawksthirdgenparts.com/index.asp?PageAction=VIEWPROD&ProdID=906)

They are used in LS1 conversions in Camaros, might be able to work for your application.  It converts VSS signals to a mechanical speedometer output.

Title: Re: VSS
Post by: Fredduck on May 16, 2008, 08:47:36 AM

Thanks ADRC, thats a cool unit.
Yes Scott, the 88 was cable driven. I bought the wrong year of Chevy Tcase for the mechanical speedo. the 1990 trucks had cable driven speedos. This t case was out of an early 93 with the VSS