Adding Cruise
I don't have wiring diagrams for the dakotas..... So, don't know if anything else uses the same reference signal. Wouldn't hurt to check a couple other sensors, and see if they are getting proper voltage though.
You can test the wire itself with it unplugged from the PCM, (disconnect the battery first.....) I would check continuity of the wire itself, (and also resistance.....) and also check continuity to ground, with both sides unplugged.
You can test the wire itself with it unplugged from the PCM, (disconnect the battery first.....) I would check continuity of the wire itself, (and also resistance.....) and also check continuity to ground, with both sides unplugged.
Welp... confirmed my fear on that I guess. Instead of testing this and that I went right to the source and backprobed the wire at the PCM. Only got 2.84V at the PCM. Went ahead and tested continuity and resistance, the wiring is fine. Guess I need a new PCM to get it working...
Well, the conundrum continues! Figured I'd hit the junkyard, no harm in trying eh? My lucky day, the truck I pulled the cruise control system from? Someone raped the PCM between the time I got the CC and today (4 days...) They simply sliced the main wiring bundle and took it. Feces. By their inventory list, was the only compatible, lo and behold, there's an unlisted one sitting in the isle! It's a 98!.... V8... sigh.
Figured I'd take a walk, picked my window for my car and found a 98 V6 Ram 1500. Hell, why not... Pulled the PCM, tried to grab the switches, but I forgot my torx... Junkyard marked the PCM as a "Module (any)" and only charged me $10. Got home, swapped it in, lo and behold... A 1998 Dodge Dakota CAN run on a 1998 Dodge Ram 1500 PCM. More importantly it gave me more results... Retested the 5V reference under the dash aaaaand. Still 3V, and the Ram I pulled the PCM had cruise. So it might not be my PCM, but now I'm really at a loss.
Wire gets 3V in column, hooked or unhooked from clock spring. Wire gets 3V at the PCM when backprobed. Wire has continuity from column to PCM, wire also shows 0 ohms resistance from PCM to column. Swapping PCMs, still get the 3V signal. Even moved a couple engine grounds around and cleaned them, no change.
So these tests rule out... PCM and wiring... If anyone has a 97~99 with cruise, mind taking the column bezel off and testing your clockspring wiring? Maybe it IS supposed to be 3V and it's just the switches (which are way out of spec from what I've found). I'll be kicking myself in the *** if it is indeed the switches and I didn't grab those today. However, I'll be taking my multimeter next junkyard run and make sure to get in-spec switches.
EDIT: Crap. Thought I hit the edit button, apparently I didn't. Ah well, double post for me, whee.
EDIT2: For those wondering, yes, the truck ran great with the ram PCM. Driving? Not so much, it did about as I figured, after a few minutes running, brake/ABS light comes on, and the transmission never shifted out of first, speedo worked. Swapped back in my original PCM back in.
Figured I'd take a walk, picked my window for my car and found a 98 V6 Ram 1500. Hell, why not... Pulled the PCM, tried to grab the switches, but I forgot my torx... Junkyard marked the PCM as a "Module (any)" and only charged me $10. Got home, swapped it in, lo and behold... A 1998 Dodge Dakota CAN run on a 1998 Dodge Ram 1500 PCM. More importantly it gave me more results... Retested the 5V reference under the dash aaaaand. Still 3V, and the Ram I pulled the PCM had cruise. So it might not be my PCM, but now I'm really at a loss.
Wire gets 3V in column, hooked or unhooked from clock spring. Wire gets 3V at the PCM when backprobed. Wire has continuity from column to PCM, wire also shows 0 ohms resistance from PCM to column. Swapping PCMs, still get the 3V signal. Even moved a couple engine grounds around and cleaned them, no change.
So these tests rule out... PCM and wiring... If anyone has a 97~99 with cruise, mind taking the column bezel off and testing your clockspring wiring? Maybe it IS supposed to be 3V and it's just the switches (which are way out of spec from what I've found). I'll be kicking myself in the *** if it is indeed the switches and I didn't grab those today. However, I'll be taking my multimeter next junkyard run and make sure to get in-spec switches.
EDIT: Crap. Thought I hit the edit button, apparently I didn't. Ah well, double post for me, whee.
EDIT2: For those wondering, yes, the truck ran great with the ram PCM. Driving? Not so much, it did about as I figured, after a few minutes running, brake/ABS light comes on, and the transmission never shifted out of first, speedo worked. Swapped back in my original PCM back in.
Last edited by Skreelink; Nov 22, 2017 at 08:17 PM.
Yep, went to another junkyard today and grabbed some apparently brand new switches from a 98 SLT. When I pulled the airbag everything inside was dusty/dirty, EXCEPT the switches, they were still shiny and clean. Maybe they put them in before wrecking the front end, the switches ohm'd EXACTLY the numbers I listed before. Also, on/off is 909 ohms and cancel is 0, so that's figured out. Also, compared to the switches I had tried, the difference in part number was the additional "AB" at the end on the 99 switches I had previously.
After installing the cruise system, I wanted to do a test and have been using cruise exclusively except where not safe. i.e. stop-n-go, traffic, etc. Even tossing it on during short trips at slow speeds. I've seen an average of .5+ mpg increase while using cruise, this seems to counter what most people claim. No real relevance, but I figured I'd post my findings, fuel up this morning was 18.4 mpg.










