Engine/Transmission (1998.5 - 2002) Tire spinning = P0500??

[AggieJustin]

Does anyone else get a P0500 (lack of signal from wheel speed sensor) code after spinning their tires for a short amount of time? It's happened twice to me now when I've been working on pulling a trailer through the mud and having to rev up and spin the tires in 4x4. Whenever I do this, the Brake and ABS lights come on and stay on for 3 or 4 start cycles and the P0500 code shows up.



I did a search on the P0500 code and came up with plenty of reading material. It appears that one of the main causes of this code is a higher than normal idle while the truck is parked. But none of these cases reported having the Brake and ABS lights on when the code was triggered.



Anyone else seeing a similar behavior?? The speedometer has been working fine, so it seems that the sensor is functioning correctly. But I have been noticing that in hard stops, the rear brakes seem to release prematurely causing the front brakes to take over all the work. I wasn't sure if this might have been related or not.



It just gets a little unsettling to see the dash light up after only spinning the tires.



Thanks,



Justin

 

[RustyJC]

Justin,



Just a thought. Is your truck a 2001 or a 2001. 5 - I'm asking because I'm trying to determine if it has 4 wheel anti-lock brakes or rear wheel only.



If it has 4 wheel anti-lock brakes, what would happen if (since you have an open front differential), the speed signal for one of the front wheels was much lower than the speed signal for the other three (i. e. , the phonic wheel for the other front wheel and the differential-mounted phonic wheel in the rear. ) This could well be the case when you're wheel spinning in the mud. Would the PCM interpret the much lower wheel speed reading from one wheel as a bad sensor?



Rusty

 

[AggieJustin]

Rusty,



It's a 2001 with 4 wheel antilock brakes. And that does sound like a possible explanation. Whenever I was spinning, it was only spinning the driver's side front tire and the rears. So it's possible the PCM thought there was something wrong with the sensor on the wheel that was not spinning. Does anyone know if this would bother the PCM?



If that is the case, I guess I need to get a locking differential up front so that all four wheels spin and the PCM can stay happy.



Justin

 

[Texas Diesel]

Me too. 2001. 5 4wheel disk, 4wheel ABS. This sucks:



4WD = ABS light + Brake light



Got in some mud today (by accident), put it in 4Hi, second gear and spun the tires a little to get out. I was rewarded with the ABS and Brake Warning lights coming on. WTF? Seems I read of this happening to someone else. Any ideas?



(Thanks Rusty for pointing me here)

 

[AggieJustin]

Isn't it great that we finally have some mud to play in (or wander into "accidentally"). Thought for a while that I'd never get to use 4 wheel drive again.



When you were spinning, do you know if both or only one of your fronts were spinning?



Edit: Almost forgot to ask, did you end up with a code when the lights came on?



Anyone else out there experiencing this problem, or have found a resolution?

 

[Texas Diesel]

All four spinning.



I called my dealer (a good one) and they said that this has come up before and DC's response is that it is due to drastically different wheel speeds. A code is set and will clear itself after 2-3 starts. He didnt know if the ABS function was disabled during the warning light "on" but I'm sure it is. It will set a code that is stored in the PCM (whatever) and will show itself as "set but not active" meaning it is a historical event. There is no TSB out for it and DC is aware of the problem. Oh boy. Who the @#$# tests these things?



And I did get into the mud by accident more or less

 

[AggieJustin]

Well, I guess that saves me a call. I was just about to call a dealer up here and ask about it.



So they don't give us a front end that will lock up in 4 wheel drive, but we do get a computer that complains when only one wheel spins.



Quite a pairing... .

 

[Texas Diesel]

My Dakota has a wire from the 4wd indicator to the ABS controller, perhaps this is why. It has 4wheel ABS and never acted like this. I sure hope DC follows through and fixes it, sure would be emabrrassing to explain to my PSD relatives and friends why my warning lights come on in 4wd :{ Can hear them now...



I'm starting to understand why some remove the Dodge badges and put Cummins in their place or others say "love the Cummins, hate DC".