Adding cruise control, 94 GMC C2500

[94GMC2500]

Hello, I have a 94 GMC C2500 6.5, 5 speed. I don't have cruise control. I have heard that it might be there and all I need to do is add the turn signal lever with cruise to make it work. Is this true? If so how can I tell?


Where do the wires from the cruise switch plug into? I did a little looking around the steering under the dash but didn't see where it might plug in, but I don't really know what I was looking for.


Tom

[sctrailrider]

I'm not sure on a 94, my 91 has a separate module on the firewall behind/ beside the hydro booster.....

[DmaxMaverick]

All DS4 systems have cruise built in, controlled by the ECM. I'm not certain about the 94 models, but the connector should be there. It is on on the 95 and later models. It's the same circuit for controlling the PTO engine speed. You may need an updated ECM chip, with cruise enabled. Some models are plug and play, while others work, but act weird when engaged (ECM limits engine power and RPM, like PTO is engaged).

[94GMC2500]

To me it looks like the little harness from the cruise control box behind glove box over to steering shaft area is not on mine.

[DmaxMaverick]

It's been many years since I did the '95, but IIRC it was the same connector as the turn signal, only with more occupied contacts. I think it was a flat card type connector, but I could be mistaking it for another model.

[94GMC2500]

Could be I am looking at the wrong thing behind glove box. Its a white plastic case about 2"x 2" with a circuit board in it.

[DmaxMaverick]

All throttle control on 1994+ 6.5L light trucks is electronic (drive by wire). There's no physical throttle to hook into.

The little box you're seeing is the VSSB (Vehicle Speed Sensor Buffer). It is essential for cruise function, but the cruise doesn't connect to it. The cruise connects to the ECM, through the harness. If the harness doesn't contain the contacts you need, you'll have to add them to the ECM connector. I haven't seen or heard of one without.

[94GMC2500]

I know that, from what I can find out the cruise on a 94 and 95 should be the same setup.

I found a white plastic box with a small circuit board in it behind the glove box. There is a bunch of wires plugged into it and a spot with 4 small terminals in it but nothing plugged into it there. I assumed it might be for the cruise control. I can't find any good wire diagrams online to see what its for.


I just looked at the long flat plug that comes out of steering column again, there are no extra wires in that plug that are not being used. There is a smaller connector out of the column also but no extra wires in that one either.

[DmaxMaverick]

The "white plastic box with a small circuit board in it behind the glove box" is the VSSB.

[94GMC2500]

Sorry, I didn't read all of your other post about the white box. I have looked at the wiring under the dash 3 times now and can't find anything that the cruise switch will plug into.

[a5150nut]

Ive got a 94. Maybe Saurday I can nose around to see where mine runs to.

[94GMC2500]

That would be awesome. I don't know anyone near me with a 94 or 95 6.5 I could look at.

[phantom309]

That would be awesome. I don't know anyone near me with a 94 or 95 6.5 I could look at.

Mebbe if we knew where you were somebody might be close,..

Nick

[94GMC2500]

I am in Berlin Wisconsin,,,