Cruise Control Problem - ECM swap??

[WMick]

I have a bit of a conundrum here... Hoping some people are a little more techy than I. especially those that have some experience with ECM configuration and scanners...

2004 Dodge Ram 1500 SLT 5.7L.... I apologize in advance for my long winded explanation...

My Cruise Control has not worked properly for a couple years... (Since the day that I had a used ECM installed, for unrelated issues. ) I called the shop at that time, and he said maybe they had a bad connection or something?? I didn't bother to take it back in and its one of those things that slips my mind until I'm on a long drive, which only happens 3 or 4 times a year... I've been having some hip and lower back problems and it would be really nice to be able to stretch my leg out once in a while.. so I finally started looking into it last night...

Checked over fuses and wiring for a bit... and whala... Cruise turned on !!

Test Drive... Turns out that the cruise will turn on and operate below 30MPH but as soon as the truck hits that 30mph mark, the cruise shuts off and I cant restart it unless I slow down to below 30... Probably been that way for 2 years. I just never bothered to try it at less than highway speed..

Google Time... Turns out that this and similar problems are often caused by bad ABS sensors on the front wheel... But here's a kicker... I don't have an ABS sensor on the front wheel... Rear ABS only.

Here's my question... that Google doesn't seem to have much experience with... What if the "Used" ECM came off a truck with 4-wheel ABS... and is expecting, but not getting a signal from the front wheel... Is this possible? and if so, could the ecm be reconfigured for rear wheel abs... and if so, what sort of equipment would be required to do so??

Just called the shop, and they had no idea... Would need to drop the truck off to have them start to diagnose...

Would love a second opinion.
Appreciate your time and thoughts...

Wayne..

 

[yoda]

You will have 1 front ABS sensor even with Rear only ABS. The PCM uses it for information mainly for electronic throttle.
I cant remember off the top of my head what side its on

 

[WMick]

You will have 1 front ABS sensor even with Rear only ABS. The PCM uses it for information mainly for electronic throttle.
I cant remember off the top of my head what side its on

Hmm - Thanks - I will need to take a closer look at that.... I know I replaced a hub recently... and I mistakenly purchased the ABS model, but didn't have anything to plug it in to.... I guess the other side might have one wired. Would you know... If I actually had a bad sensor, should the ABS light come on? (which it doesn't)..

If the sensors match, I might be able to to just swap the un-used sensor from the other hub... and see what happens.....

Curious - When I look at the cheaper DIY code readers, some say they are good for ABS and some dont.. Will the ABS compatible readers actually display a wheel speed while driving?

Thanks again.

 

[yoda]

I looked it up, The sensor should be in the left front (drivers side)
Not sure if it would trigger an ABS light, I would think it would set a DTC in the PCM but not positive.
They only ran that settup a couple years if I remember correctly, thats getting to be a long time ago and I cant keep all this crap in my head anymore