94 RAM 1500 Cruise

Hey....(Tony or anyone else)...

What does anyone know about why a 94 Ram1500 might not have the Cruise working? I've checked the fuses under the dash & the hood...I even changed the cruise "head unit" under the battery...and according to my neighbor (who had a working multimeter) there was no power to the "head unit".

But, methinks, if the cruise isn't available below 30-35mph (been awhile since I had a car with cruise that worked) i'm not sure if it would actually HAVE power sitting still in a driveway.

Anyone...? anyone....?

thanks

I don't think you will show power to the head unit sitting still. The cruise will not engage below 35mph. I don't remember for sure if this unit has vavuum to it but if it does you may have loss of vacuum. I think it may also have a relay along with fuses, I will check and get back with you. If the relay is bad you will loose cruise.

You could have loss of vacuum. You might check the vac reservoir and your lines. I check vac lines with starting fluid. With the engine running spray it on the hoses, if there is a leak you will hear a difference in the engine. How is your speedometer working? It may have something to do with a speed sensor also. It could have an efect. I once had mine go bad, the speedo still worked but the trans would not shift out of first. Sounded strange to me but it could be bad and the cruise does work from that.Let me know what you find.

Any development on this? I am curious to know about the relay that was suggested. Where is it located? Did you have any luck fixing it? Inquiring minds want to know!:grinyes:

Okay...
Prior to changing the "head unit" for the cruise, I did check to see if I had vacuum....which I do. It goes all the way back to the pass side of the 318. Now prior to this, the HVAC vacuum had melted closed, which i've since repaired and it's fine ...which i thought maybe the two were related.

The "Vacuum Reservoir" is under the windshield, if I understand the diagram correctly. How will I know if that's working or not, or will it not work even if my heater goes from DEF to FLOOR and back again (also vac controlled)?

Speedo is fine...no problems...but the truck doesn't shift real easy out of 2nd into third on accelleration -- but that is an intermittent problem and a trans shop gave me a nightmarish estimate about replacing it. (it works at least for what i need it to, i'm not going to worry about it)

Lemme know...i forgot to check back on this as i've been in the middle of a few other projects.

THANK YOU TONY! :)
-- Ray --

it is possible your speed sensor is bad, it does not have to quit working entirely to send bad signal, that could possibly effect tranny and cruise. Check canister by spraying it with starting fluid while motor is running, you can check any vacuum this way, if engine idle changes up or down, you have a leak.

Will have to give that a shot in the next couple days...supposed to snow tonight & tomorrow...dont wanna get under there unless it's life-or-death. :)

Would that intermittent speed-sensor problem be okay when it's cold or warm and then bad when it's the opposite?

>Ray

Will have to give that a shot in the next couple days...supposed to snow tonight & tomorrow...dont wanna get under there unless it's life-or-death. :)

Would that intermittent speed-sensor problem be okay when it's cold or warm and then bad when it's the opposite?

>RayTemp shouldn't have an effect but I guess its possible. It is electric. If you change it, its simple, unplug harness, unscrew sensor, just have the new one ready because fluid will escape nad you want to lose as little as possible. Did you find out if there was a relay for that? I should sak, when you start your truck and push the on button for the cruise, dose the cruise light come on on the instrument panel? That tells you that it is activated and ready to use. If it doesn't come on then I think your problem is electrical, the button or something.

If the throttle position sensor gives wacky readings it will cause the cruise to malfunction. It will cause the cruise to act dumb, and then it just won't work at all.

Check your throttle sensor.

Is it possible for the throttle position sensor, or even the speed sensor to malfunction and give wacky readings without tripping a code and displaying check engine light? Just curious..My truck has no cruise display when button is pushed but what has got me thinking is that I have noticed a bit of a stutter when tranny shifts gears...especialy when pulling the ski-doo trlr under acceleration. After the input on this thread it makes me think the two are related, but I do not have any codes showing...What do you think?

I don't have a light of any kind for the Cruise (that I know of). I know in the newer ChryCo vehicles, there's a light comes on when you hit the Cruise (usually on the odometer readout or somewhere...but haven't looked for the light either.

I just went out with a flashlight to see if I could find a light on the Instrument Cluster...nada found anywhere there SHOULD Be one.

The Relay would be a good start...but i'm not sure where to look for it (under hood or under the truck itself)...

Since we didn't get the snow we were expecting, I might be able to check the vacuum and see about whether the vac reservoir is bad (you had mentioned about the engine rev going up or down).

As far as the TPS...not that thing again...(ref to another problem on TWO separate cars (concorde & my no-longer-owned Saturn)).

I own a 94 Ram and have never seen a cruise light on my instrument panel. As far as I know there ins't one.

I was not sure about the light, my 99 has one to tell if cruise is on ready to use. Sorry about that.

It could also have a bad cruise control switch or wiring(In steering wheel) or clockspring(located behind steering wheel). Before you remove the airbag, disconnect the neg. cable from the battery first, and wait 2 min. to let the system capacitor discharge.

Would there be any help in just jumpering the cruise power leads to live power (battery or fused link) to check it...or maybe just to rig it in order to get it to work?

>Ray

I wouldn't do that you could possibly fry something more.

I wouldn't do that you could possibly fry something more.

Don't jerry rig your cruise. Think about it...Your cruising at around 60mph..

Well, the thought wasn't to actually use it on a regular basis that way, just for test purposes...but i get the point.

I was installing some "foot" lighting yesterday on/off with the dome light--(a nice detail btw) and noticed a yellow molex plug that was fastened to the metal "U" shaped crossbar right above the hood release. I unplugged it, replugged it and i do know it's not the horn...but it does snake up the column. What does that connector, connect to? Airbag maybe or something else? The wires were dark green & black.

Thinking again...put a test meter on it.

-- Ray --

That was the airbag wires. Avoid unplugging them with the battery connected, and DON'T check it with a meter..

Well...

I unplugged it (yesterday) and re-plugged it...nothing happened.

Do I need to get something checked now or is it fine?

- Ray -

you should be fine. download the manual and you will have better luck knowing whats what

Looking through the manual, I notice the wires listed are two vac controls, a brake control, and a ground.

Can I somehow put some other switches on this for testing purposes since its a possiblility that it's the Clock Spring that's bad inside the column?

ALSO...i just checked JC Whitney's site (i get regular emails).

They have an aftermarket Cruise unit....could I possibly wire that using any of the existing controls or servo or something?

I just wondered too, if i could put a meter on the wires under the dash that go to the cruise buttons and see if maybe that's the problem or if it's up in the ClockSpring...

just kinda dumbfounded...thats all :)

Let me know...i appreciate all your help!

Check the main wiring harness on the driver's side of the engine, where it turns down towards the tranny. Look for melted/shorted wires.