07 Grand Caravan Rear ABS sensor (7th bad sensor)

So the wife is going in a couple weeks to visit the family. She'll be driving our 07 Grand Caravan roughly 6000km (round trip).
I've taken care of all the outstanding issues and regular maintenance except for the brakes (going to change the pads and rotors) and fix or replace the rear ABS sensor. If I replace it, it'll be the 7th sensor to go in (previous 6 where under warranty.
Having never touched the ABS sensors on this vehicle, I'm wondering if anyone knows what the common fault is with these things. Is it corrosion, poor connection, dirt?
We've been driving with it on the out for over a year now, but with the wife taking the kids, and my not going, I want everything as perfect as possible to avoid having to pay a mechanic while she is out and I'm home.

From my reading, these ABS sensors, airbag sensors and rad fan control relays are fairly common with this generation of grand caravans. I've replaced the Rad fan relay this month, and repaired the pinched wire for the front crash bar sensor this past weekend. Also fixed a small evap leak with a quick hose replacement. The ABS is the only dash light/code left.

 

Usually sensors that are exposed to high heat have short lives. That sensor bolts to the top of the differential....right ? You wouldn't expect that to run that hot and have a reduced life.

 

I had to replace one on my Ram 3500, and it is fairly simple. I think the fault with having them in the differential is the viscosity of the fluid that is splashed on the sensor. Basically dirty and causes fault, not sure. I also had to replace the under hood ABS motor controller. Not sure if the Caravan has that or not. Be aware, it is VIN specific. Don't do as I did and buy one off Ebay. Although the person I bought it from was a rebuilder and had no idea of the VIN thingy. He graciously took my return unit and rebuilt it and sent it back to me for a swap and it worked flawlessly. Now, the only thing with the non VIN unit was the light on the dash. I had ABS function (tried it out on a gravel road with a trailer behind me inadvertently), just the obnoxious light.

 

PJmax; Don't think heat would be too much of an issue. The rear doesn't see a lot of braking power (weight transfer and what not), plus it is a grand caravan, so it's not exactly driven hard. We also don't have a hitch, so it's never towed anything. I'm really kicking myself for not taking the hit on the expensive dealer hitch and at least have one. I opted for going aftermarket (at less then half the cost), and ended up never getting one.

Good to know Larry. I noticed in my google search a couple sites popped up detailing how to clean the wheel sensor (and many, many selling them). I'd guess probably a couple of my warrenty replacements where probably the tech wiping off the sensor head and billing for a new sensor.

I have zero faith or love for the local dealership (in Sudbury that is). I could go on and on ranting about them, but will leave it at I tore a strip off the service manager for charges I had to pay for warrenty work. The owner indirectly refunded me (tracked down my parents that he knew and funnelled the money back to me through them). I guess my outloud statement that their service tech should not be allowed to hold a wrench if he can't follow basic written instructions that are word for word right out of the Dodge service manual.

Edit: Oh, sorry, starting to rant.

 

It's OK. That's how I found out about the VIN specificity. Knew I had to take it to a dealer to get it initialized to my truck. Well, an hour later and $75 poorer, the service guy told me they couldn't initialize it, and it was a VIN specific item. I basically did what you did, but I couldn't find anything to throw. I go out of my way not to even drive by the dealership

 

Not to take the thread too off topic, but....

What happen with my last incident was I took the SRT4 in for a bad shock front shock and to have them torque the front drive axle nut. I would have done the nut myself, but I didn't have a torque wrench that does 185ftlb.
So, made the appointment (specified over the phone the work required) and on the drop off envelop, specified it was the front passenger shock and to torque the front driver axle nut to 185ftlb using a 32mm socket (pretty sure it was 32mm, can't remember now).
Pick the car up, ABS, traction control and a few other lights are now on, the shock is still making noise and now I have a squealing sound. No one said anything until I called 2 minutes after leaving the dealership.
They broke the ABS speed sensor changing the shock and it was on order (would have been nice to know when I got the keys), and changed the wrong shock (rear passenger). The squealing noise was the front driver bearings (axle nut too tight).

So, 2 days later, back in it goes. Keep in mind, I live 50 miles from town, the dealership is 5 miles from work (and it's 6AM). So I have to have the wife (and kids) come into town with the van as well to do this drop off.

Pick up the car for the second time. Christmas tree lights (aka my dash) are off, they changed the proper shock, but couldn't find the noise. This is all under warranty btw.
I get a bill with my keys for $35 for hoist usage because their teck (I have other names for him) couldn't find the noise.
My rant (short version, a little more G rated as well), "How the hell does the tech change a shock and ABS speed sensor without using the hoist? Did he have to lower the car, then raise it again because it was another **** line item on the work form? How am I expected to pay for your <insert not so politically correct wording for tech> lack of skills and abilities?"
There was more, but you get the point.
The service manager and sales floor managers walked in by the end of the rant, after I already paid with debit. They told the girl behind the counter (feel sorry for her, she had nothing to do with what happen really) to refund the money. I said keep it, it'll be the last $35 hoist usage fee they'll ever get. As mentioned earlier, I got it back indirectly.

Anyway, that is totally off topic.
With the current track record of the ABS sensor(s) on this van, it's a fairly sure bet it's the sensor on the same wheel as every other time before. Luckly it's not a VIN specific item and is a common part everywhere.
Think I'll pick up a new sensor, but try to clean it first. If cleaning works, part gets returned. The up side with the 07 Grand Caravans is their adaptive memory (and code freeze frame storage) is easily reset, so I should know right away if all is good, or if I need to swap the sensor. Shouldn't need to even put the wheel back on to find out.

Edit: Apologies for the rant.

 

Hey....it's your thread.....you can wander if you want

 

Ya, but I should know better and lead by example.