Vss

[Ranger6202]

Was hoping you get some insight here. I'm bolting a 6.0 to my th400 and am wanting a VSS so i don't have to chance whether it runs good without it or not, and i wouldn't mind Cruise control later. Anyhow, do i have to match the pulse per mile or will any pulse # work? I found one at Dakota Digital for about $35, but they were saying it puts out 8k and it might not work. These guys have the 40k VSS
http://www.jagsthatrun.com/Pages/Spe...eedometer.html
but it costs double.
I thought i read somewhere that you can change the ecm to accept whatever pulse just to see its moving and to have a signal for the cruise to hold to. Mind you that i'm keeping my cable speedometer and won't need an accurate signal.
What say you lsx swappers?

[Shon]

PCM can be changed.
Cable style set ups have run without a VSS, I have a DBW running without VSS and he says there is issues when stopping but when I drive it I do not have issues so I dont know whats difference between our driving styles....

[Ranger6202]

Do you know if the Cruise would work with a different signal. If i were to guess i would say no since in theory its just trying to hold to a signal pulse. But i don't know for sure.

[Shon]

I really do not know, have not tried to hook up a cruise in a swap.

[Clyde65]

What are you putting it in?

[Ranger6202]

'85 crew cab
http://67-72chevytrucks.com/vboard/s...d.php?t=504827

[Ranger6202]

So i stumbled on something else that might be a possibility. I'm thinking probably not, but its worth the effort to ask you guys. I noticed on jagsthatrun, they had a pdf that explained VSS's. One of them was a two-output vehicle speed buffer. It was used for cable driven speedometers. Turns out, i have that very one dangling under my dash. According to the pdf is uses and optic head to watch the speedometer. And so my question to ya'll is this: can this buffer be used as the vss i need for my pcm? Or is the square wave created by the buffer the absolute wrong signal to be used in the PCM?

[Clyde65]

I think you can tune out the pcm's need for VSS. Ask your tuner. If cruise is what you want just hook up the old 85 stuff
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[Crash_OK]

Have you looked at these?

http://www.jagsthatrun.com/Pages/Spe...eedometer.html

[Ranger6202]

yup i have

[Crash_OK]

Originally Posted by Ranger6202

yup i have

Yes, I guess you have... Should have read your post in a little more detail..

Sorry about that..

[Ranger6202]

no its all good. I thought about getting the jagsthatrun vss, but i'm a cheapo and saw the Dakota digital one for half the price and figured i'd save a few $ to put towards the ecm and tune

[Juiced06GTO]

I run the Dakota Digital Vss. It was working great, but I think either the gear striped out in the trans now or the cable broke because I have no signal coming from it now, but that is another issue for another thread! You can tune the pcm to accept the output from it. I occasionally have issues now that there is no VSS, it will stall at lights and high idle on occasion Good luck!

[Ranger6202]

Wiring question. I noticed on the PCM pinout for the Red/Blue connector on pin #49 it says 128k VSS output and on pin #50 it says 4k VSS output. I'm guessing you need both for the 4l80 and just one for the 4l60. Or am i backwards on that? Also, since i'm just going to the TH400, do i use the 4k wire -> VSS -> ground, or 128k wire -> VSS -> ground, or do i take either of those combinations back to the PCM instead of to ground?

[Ranger6202]

one more thing to add, was just digging though some schematics, i see that there is a VSS high/low on PCM green connector at #20 & #21. From what it says, 20 and 21 are the low and high, and 50 is vss out to antilock system and 51 is out for instrument cluster. So to edit my earlier question, what wire goes where in the vss hookup?

[Crash_OK]

Originally Posted by Ranger6202

one more thing to add, was just digging though some schematics, i see that there is a VSS high/low on PCM green connector at #20 & #21. From what it says, 20 and 21 are the low and high, and 50 is vss out to antilock system and 51 is out for instrument cluster. So to edit my earlier question, what wire goes where in the vss hookup?

If I understand your question correctly.
PCM (Green) Pin 20 --> VSS connector Pin 2
PCM (Green) Pin 21 --> VSS connector Pin 1

Is this what you need?

[Ranger6202]

yup, that's what i was thinking and was asking, thanks Crash

[Crash_OK]

Originally Posted by Ranger6202

yup, that's what i was thinking and was asking, thanks Crash

No problem.. Hope it helps..

[Ranger6202]

I read a little more and figured i'd post what i found just to help whoever is looking up VSS info.
Pin 20 (lt gr/bk) and 21 (ppl/wh) on Green connector is your two connections (low and high signal respectively) that wire to your VSS. Pin 49 (yel/bk) on Green connector is your VSS output to your antilock brake system. Pin 50 (Dk gr/Wh) on Green connector is your VSS output for instrument cluster. Pin 14 (Org/bk) and 15 (DK bl/wh) on Blue connector is the Serial data (based off VSS info.) to your TAC for cruise control.

--Mind you, this is all based off of 2004 truck schematics and ecm pinouts--

[nacho55]

Can I thread jack this and ask another question regarding the green vss output, can this lead be used for a signal for an after market speedo..
Posted via Mobile Device

[Ranger6202]

According to the schematics its for the gauge. And i think i've read in a few places you can change the PCM to get the right signal. Whether its changing the signal from the VSS to the pcm to get the correct output to your speedo or its just changing the output signal to your speedo, i don't know since i haven't ever tuned before.
As far as thread jacking.....ask all the questions anybody wants. I was just hoping to build a thread just about the VSS and related components. You can do searches, but it always seems to be bits here and there and not the whole story.

[nacho55]

I did some looking and According to the lt1 swap site it puts out a 4k signal so this might be more of a question for my gauge manufacture if that is the right signal.
Posted via Mobile Device

[mcmlxix]

Originally Posted by nacho55

I did some looking and According to the lt1 swap site it puts out a 4k signal so this might be more of a question for my gauge manufacture if that is the right signal.
Posted via Mobile Device

http://www.speedhut.com/custom_gauge...number-777.htm


"Programmable from 500 - 200K pulses per mile."

[mcmlxix]

OK. Can we get a list of VSS outputs and ECM signal needs? I have a 2005 6.0L, a 4L80e and a NP205. I know the 4L80e has two VSS connectioins, but I read somewhwere that in the 4x4 application, the second (farther towards the tailhousing) doesn't have a tone ring to generate a signal and the ECM gets its signal from a VSS on the transfer case.

[Clyde65]

Most aftermarket electronic speedo's need the signal right off the vss from the tranny, that was my experience with an Autometer and a Dolphin electronic speedo.