Cruise Control Question

[dsnyder]

I just purchased a 1994 6.5 Turbo Diesel Suburban and I absolutely love it!!! Right now I am trying to get the cruise control working but I am a bit confused. I'm new to this vehicle so if my questions seem stupid, my learning curve is steep right now!

Where is the cruise control module that the article from this website writes about? I've looked all over the driver's side firewall and I can't find a module and I can't find any mounting holes either (in case the previous owner removed it). I did run the VIN number and it states that my vehicle was equipped with cruise control. There is a cruise control switch on my column- it just does not do anything.

Any thoughts on where to start?

Thanks!

[bobt]

If I recall correctly, on my '93 C3500, it was attached on/near the brake master cylinder.
Bob

[john8662]

94's are electronic no cable-driven cruise control (unless retrofitted of course).

The most likely issue is the switch on the column, or a sticking brake switch, etc.

There is no cruise control box on the firewall, the cruise is all integrated into the computer, because the injection pump is electronic so the computer regulates the fuel output to run the cruise.

[dsnyder]

OK that is sort of what I suspected- Is there a troubleshooting chart for the drive by wire cruise control anywhere?

Dave

[JohnC]

There's not much to it. Three modes of failure I can think of.

First, if the turn signal stalk switches don't work, it won't turn on or set. There is (I think) an indicator light on the dash. Does it work?

Second, (very common) if the brake light switch is telling the PCM the brake is depressed the cruise control will not engage.

Third, if there are any faults detected by the PCM with respect to the electronic throttle control, the cruise control will not engage.

Check the brake switch first (there are 3 different contacts in the switch; the brake light can work and there still be a problem.) If that doesn't net a solution, you may need a scanner to go farther.

[dsnyder]

I'll go through your suggestions tonight-

The indicator light does not come on.

I don't know if it is related but the vehicle runs real nice but if you mash on the throttle hard, it stumbles and misses. I'm running some Seafoam Cleaner throught fuel system and then I'll change the fuel filter.

I've read that the causes of a stumble can be the filter, the uplift fuel pump or the pump control module. The module was replaced by the previous owner and moved up to the front of the vehicle but the module could go out twice I guess...

[handcannon]

There is (I think) an indicator light on the dash. Does it work?



I have a 94, been driving it since May. To the best of my knowledge there is no dash light, at least I have never seen one on my dash. I have two Astro vans, 97 and 98, and they have the same switches and function the same as my pickup, or at least the way the pickup should function (resume/accelerate button doesn't work right). Neither one has a dash light though they could easily be totally different than these diesels.

Don

[Warren96]

I have had my 94 since new, and there was never a light on the dash.

[suburbanK-2500HD]

Here is the el.shematic for your truck. might help.. :)