Thanks

And if not, then can someone explain to me how it works then?

 

Not on an 89.. There, the signal is generated behind the speedometer and split from the buffer. One signal to the ECM and one to the cruise.

On later cars, a signal is sent from the tranny to the ECM where it's split internally and sent to the speedometer and cruise seperately.

In other words, ditching the computer is easier on 89s than 90s.

 

Ok, so you are telling me that if i went carbed or with an aftermarket computer......my cruise control would still work?

 

TTT

 

It should. Assuming you don't hack up everything taking it out.

The signal wire is a brown wire, which it split right at the cluster connector. So the signal's first leg of it's trip after it's spit out the buffer is through the printed circuit on the back of the cluster to the right-hand side cluster connecter, where it's split. One goes off to cruise-land and the other goes to computer-land.

 

ok, but with my aftermarket computer if there is nothing in there to control that other signal, it wont work right?

or am i wrong and missing something?

 

How about my 88 T/A (see sig)??? How does cruise work on this car? Also, if I were to go with an aftermarket computer system, what do I do about the transmission, or does the stock computer even control the tranny?

 

TTT

just trying to figure out if i can still wire up the cruise control and make it work with my FAST system

 

TTT on this.....car is getting ready for the new motor to go back in and would like to know if there is a way i could still make it work

 

yes, it will work as long as the speedo head still has an operable vss buffer. The cruise has it's own control module independant of the ECM.

 

Ok, 2 things:

1) good news and thank you for responding

2) i am not too good with electronics...what exactly is a VSS buffer and how would i know if it is operable?

Does this help?

i have a mechanical speedo and it will still work, i dont have a factory 700R4 tranny though

Thanks for the help

 

The VSS is located on the back of the speedo head (assimung it's a stock one). As long as you haven't messed with any of the wiring, it should be working. From the buffer a brown wire run to the cruise module and also splits to run to the ECM. Finding it is a matter of hunting thru wiring either where the ECM was or, at the harness where the ECM plugged into the regular underdash wiring. The VSS buffer puts out a pulsed (varies with speed) 5v signal.

 

Yup, i haven't messed with the speedo. I haven't messed with the cruise wiring, just "unplugged" it. I didn't cut any of it out in case i could still make it work. Ok, so this brown wire. How important is it? I have absolutely no stock computer anymore, so did the stock ECM give it the pulsed 5v signal?

If i'm understanding this correctly....i'm going to have to generate a pulsed 5v signal somehow on my own to get it all to work?

 

If that's the case, plug the cruise stuff back in and enjoy
The VSS buffer converts the signal down to 5v and sends it to the cruise and ECM via the brown wire.

 

Thanks a lot, i get it now. My friend explained to me that the brown wire just acts like a "signal" wire to tell the ECM the cruise is on but doesn't actually do anything.

AWESOME. Now i just need a new cruise moduel thingy with the cable...to the junkyard i go

 

The brown wire actually 'tells' the ECM how fast the car is going as well as the cruise.