ls1nova71

iTrader: (4)

You can just use a single set button, you'll just have to wire the on/off wire to an ignition hot source. You just wont have resume/accel, but you will have the set/coast part.

Tompitomas

Ok, thanks for that. Then either the cruise control module is not working or I haven't got the right vehicle speed sensor. I will check the signal from the VSS.
I got three VSS cables, one is used to the speedometer and the other two I have tried to use for the cruise control.
Is it possible to check if the module is broken?

ls1nova71

iTrader: (4)

The only way I know to check to see if the module is bad is to hook it up to a vehicle that has a working cruise, not the easiest thing to do. You say you may have wrong VSS, what engine/harness are you using?
Before I would write it off as bad, I would check your wiring real good, and make sure you have 12v on pins A and F, then check to make sure you're getting 12v on pin B when the set button is depressed. If that checks out, check for power at pin D with the brake pedal NOT pressed, you should have 12v. If still good, have someone step on the brake pedal and check for power at pin G, should be 12v. Do all these tests with the key ON, but engine doesn't need to be running.

One other thing, if you have LED brake lights, you'll need to add some sort of a load to the brake light circuit as the module needs to see a ground through the brake light bulbs and LEDs only flow current one way so they wont do that so the cruise wont work without it.

Tompitomas

The engine harness is from the same vehicle as the engine, so is the cruise control module. But I have an EZ-Wiring harness for the rest, lamps etc.

Tompitomas

Hello
I did as you said LS1Nova, checked the voltage on the posts. It was wrong on the one that is connected to the brake light. For some reason it showed 11 Volts, when not braking and 14 Volts when braking. Anyway, I connected the terminal to ground now and it works. Thank you for the help!

socorob

Re: 4000 PPM. I found out my cruise works fine over 75-80 mph. 65-70, it will come on for a little while then shut off. Mine is hooked to my T56. Is the T56 not sending enough of a pulse? Can I hook it to the PCM?

1986LxLs1

I have a 1994 c1500 with a 5.3 swap, tried adding cruise control and even switched modules, checking wiring about 5 times or more, everything checks out, the only thing that has me wondering is the truck has a LED third brake lamp, could that possibly be the reason the cruise will not work??

ls1nova71

iTrader: (4)

If you are using most of the original cruise control wiring in the 1994 truck, then yes, this is probably your issue. Pretty sure the brake light part of the cruise control wiring isn't hooked to the actual brake lights in that new of a vehicle, like you would do if you were doing a swap on an older car, but rather it's hooked to the 3rd brake light. Add some kind of a load to that circuit and I'd bet it will work for you. If you have the original light, hook it back up and see what it does. If not, temporarily hooking up something like an 1157 bulb will do it.

1986LxLs1

This truck did not originally have cruise but I added a cruise tilt colum and tied the wiring into the brake switch, I no longer have the OEM brake light... I will hit the junkyard in a few days and see if I can find one to try

1986LxLs1

I changed out to a 2001 silverado cruise module, same year as my engine and trans, did test on the plug once more this morning, everything is in order except for pin K.

with the plug inserted into the module and volt meter hooked to pin K voltage read 10.30 volts (also got same 10.30 volts with it unplugged as well)

I placed the rear of the vehicle on jack stands, started up the truck, voltage still read 10.30 , pressed brake, placed vehicle into gear and let the speed get up to 45-50 mph, the voltage got up to around 11.95-12 volts

do you have any suggestions?

ls1nova71

iTrader: (4)

I have no idea on the voltages, I have never checked them. I can say without a doubt that you CANNOT test the cruise on jackstands! There isn't enough resistance on the wheels so they will very easily and very quickly go past your set speed and wont be able to compensate for it. You must test it on the road unless you have a road simulator, dyno type set up with rollers, but nobody has that at their house. LOL Test it on the road and get back on here with your findings.

1986LxLs1

took the truck for a drive,

Key on , engine off 9.1 volts
Key on, Engine running 10.7 volts
vehicle in drive and operating at highway speeds 5.6 volts

I have pin K and My factory Speedometer both connected to PIN 50 on the C2 Red connector

ls1nova71

iTrader: (4)

It sounds like it is wired up right, and having the speedo and cruise on the same VSS output doesn't matter, that's the way I hook up all of mine. So going back to the basics, what exactly do you have the brake switch wire hooked up to? Is it tapped in right at the brake switch? Do you have both of them hooked up, the normally open and the normally closed ones?

1986LxLs1

wired directly to my stock 1994 brake switch, i even swapped a halogen 3rd brake light back onto the truck as well

this is what has me thinking it's the voltage, it came from the first post in this thread by the OP:

Cruise module connector terminal K is the speed signal terminal. During operation the voltage will oscillate between the following levels:

A high of 4 to 5 volts
A low of near ground

ls1nova71

iTrader: (4)

Like I said, I don't know about that voltage because I have never measured it. Does your speedometer work? If it works, then you're getting the correct 4k ppm signal to the module, and it has to be something else. A lot of times when they don't work in a swap, it turns out to be a brake light switch issue. So does the speedo work?

1986LxLs1

yes, the speedo works correctly, I will go over the wiring once again

ls1nova71

iTrader: (4)

Ok, so if the speedo works, we can rule out a VSS problem as long as you have a good connection where the wires are connected, so check to make sure it's good. From there, you need to check the brake switch real good. On the brake light switch there should be 4 wires, orange, yellow, pink and purple. These are the wires you need to use. I believe on some trucks there is another switch on the pedal with 2 wires, gray and brown, that originally went to the cruise control, but you said your truck didn't have cruise, so you shouldn't have that. So anyway, the orange wire is the constant hot to the brake lights, so should have 12v with the key on or off, Check to make sure there is power there. If that checks out, press the brake pedal and check for power on the yellow wire. There may be 2 yellow wires, I'm not sure if that is where GM spliced off for the cruise control or not, but they sometimes do. If your brake lights are working, which I believe you said they were, you should have 12v on the yellow when the brake pedal is pressed, let off and you should have 0v. If you have power there with the pedal pressed, unhook the connector at the cruise module, and check for power on pin G. You should have 12v when the brake pedal is depressed and nothing when released. If that checks out, then it's time to move to the other part of the switch, the TCC portion. The pink wire should have 12v when the key is on, check that, if it does, check the purple wire, it too should have 12v when the key is on and the brake pedal NOT depressed, then 0v when the pedal is pressed. If it does, go back to the cruise module plug and check pin D, it should have power whenever the key is in the ON position, and 0v when the brake pedal is depressed. That should take care of the brake light portion of it. If all that checks out, then let me know and we can move on to the cruise switch testing, I have seen the wiring inside the column break which could also cause issues. One other thing, make sure you have good power and ground on the module plug it's self, you can check by hooking a test light between pins E and F, the test light should light up when ever the key is on.

Dewey Nunez

I have 1998 gmc Sierra1500 5.7 v8 installing a new cruise control module . Has a yellow ban connecting to the cable going to the throttle linkage . would like the correct procedure to connect up the cable to the cruise control module get rid of the slack .. so i dont mess it up ? If you look back 5-14-2010 #56 shows what im talking about . Thanks DJ

jshort74

I know this is an old thread, but it seems to just keep helping people. I'm swapping a LQ4, 4L80E and cruise into a '72 blazer out of a 2001 2500 Silverado. I have the entire truck. I'm just wiring everything up now. I'd like to use a multi-switch that is normally open so that I don't need to add the 3 relays. I just want to confirm how you have been doing these. I'm guessing (I can't seem to find official documentation anywhere) that the stalk out of a mid-80's GM car (GM# 19244690) has normally closed switched in them? So, what you are doing is disassembling the 80's multi-switches and removing the internal switch assemblies then you disassemble the multi-switch out of an early 2000's vehicle and put the internal switch assembly from the 2000's vehicle into the mid 80's multi-switch? Right? So I could just pull apart the multi-switch in my donor 2001 Silverado, then get a GM#19244690 somewhere, take it apart and put in the switch assembly from the 2001 Silverado? Sorry, sometimes I need spoon feeding, but I really appreciate your help!

ls1nova71

iTrader: (4)

The mid 80's switch you listed will work, but the hard part is it won't mount to an older steering column. The newer 2000's switches will also work, but again, won't mount to your column. What you need is a lever out of a 1981 Chevy/GMC van, or 1981-84 Chevy/GMC truck. Those are pretty much the only levers that will bolt to your column and be able to have the internal switch replaced with the later switch. Replacing the switch isn't super hard, but you have to be careful because they break easily.