Cruise won't turn on or work. No light nothing

Changed out button on steering . Changed clockspring and brake pedal switch ..no change ..

Please help ..I'm one of those idiots that needs it to work or I speed EVERYWHERE


2008 dodge ram set

1500 v6 2wd

 

Having the same issue in my 2004 RAM 1500 5.7 HEMI 4x4.
I also changed the clock spring ("CRUISE"-light wouldn't even come on before), now light gets on but will only engage between 25 and 40 mph.
Going above approx. 40 mph and the light will turn off and the cruise control will disengage.
Changed the brake switch today, but no change.

Will change out the front left wheel speed sensor, as I read it may be the culprit.
Any other things that I can check? I checked my "c-codes", but nothing...

Thanks for your help!

 

OK, so I replaced the brake light switch, the front left wheel speed sensor and the gearbox output sensor. Same problem - can activate at around 25mph and it will go off at 40mph.

Any ideas?

 

No one here that could help please?
I measured the front left wheel speed sensor, at least seems to be OKish at around 1k Ohm resistance.

Which speed sensors are involved in the cruise control system anyway?

Thanks!

 

You need to plug in with a scanner, and see what the PCM is seeing for speed, and that it is getting the right inputs from the switches.

 

Thanks for your reply.
What scanner can be used? I searched online but could just find scanners that are compatible with the 2006+ models, not my 2004 model though.

And what sensors are used for the cruise control? I replaced just the front left one, maybe the front right one is faulty?!
But wouldn't that also trigger an ABS fault? Or only when braking hard/into ABS?

 

So far as I know...... (which ain't real far. ) PCM gets vehicle speed from that left front sensor, which should be all it needs.... the others are for the ABS. If one of the other sensors is screwing up though, that may cause an issue. Of course, it may be a short in the clock spring too, but, it's way too consistent for that. Cruise is controlled by the PCM. The switches on the steering wheel just modify a signal from the PCM, to clue it in to what you want. Under normal circumstances, there IS a 'minimum speed' at which it will set. I think there is also a maximum speed over which it won't set..... but, I am quite certain that's higher than 40mph..... The fact that it just turns cruise off is curious, but, so far as I know, (and again, that ain't real far....) the PCM will only turn cruise on/off if the driver actually pushes the corresponding button.... Apparently, there are other reasons it will do so. I would expect that it would need to see a fault somewhere else to prompt it to do so. Maybe the cruise module itself has an issue??

As for scanners, there should be any number of them out there that will talk to your truck. The cheap ones will generally only read codes, the higher zoot fellers will also read live data, which is what you want to be able to see. Unfortunately, those also tend to be expensive..... couple hundred bucks at least. (running into the thousands for something like a Snap-On Solus.....) There are a bunch of sites that compare scanners. Have a look, see what you can find, and how much you wanna spend. Go from there.

 

Thanks for your reply.
OK, so the left front sensor is new, I also measured the old sensor and it was measuring around 1k Ohm resistance so should have been working, too.
I read that if the rear differential speed sensor sends wrong data the PCM will switch the cruise control off. But a defective rear speed sensor should give problems with the speedometer, too? I don't have any issues with the speedometer though.

And I did search for scanners and checked them all. The cheaper ones (around 200US$) are able to read engine, airbag and ABS systems. But only for 2006+ models.
I also found out that there are "copied" DRBIII-scanner emulators from China? But I haven't found any info on that.
Maybe I will have to ask at a former Chrysler service center if they can read out my car.

Thanks a lot again for your help!

 

I *think* the speedo gets its cue from the left front sensor as well..... but yeah, it seems reasonable that if the PCM sees disparate readings from the various wheel speed sensors, running on cruise control might be a bad idea. Really need to see what the sensors are reporting. Though, if even one of 'em was significantly different from the rest, or just reading erratic, I would expect that to set a code......