ABS Light? - Diesel Forum

Motogrl307 · 11-17-2006, 09:00 PM

While driving 70 the speedo dropped to about 20 then the ABS light came on and the speedo went back to normal and light stayed on. Stopped for fuel and when started back up light was off about 30 miles later the cruise kicked off and speedo dropped again, did this 3 times then the ABS light came back on and stayed on and everything else was fine again. Any ideas? [img]/ubbthreads/images/graemlins/shrug.gif[/img]

2004fx4 · 11-17-2006, 09:27 PM

VSS (Vehicle Speed Sensor) in the rear axel is going.

Motogrl307 · 11-17-2006, 09:43 PM

Ok thanks will check it out.

beetruck · 11-18-2006, 02:14 AM

I'm on my 3 sensor now the light comes and goes I heard that they just make bad sensors and guess I'm buying the bad ones so 1 day I change it again

GrampyJim · 11-18-2006, 03:07 AM

While the rear sensor is the most common failure (we usually wind up replacing the pigtail at the same time due to the nature of our terrain), this sensor is not the only cause for ABS light illumination.

If anyone is experiencing repeat sensor failures, it is reasonable to assume that the symptoms are being addressed, but the root cause is being ignored

tedncindy · 11-18-2006, 09:04 AM

I pull a 16k toy hauler. Last time out I was driving down the interstate and hit the brakes hard (FL drivers) and the ABS light came on. From that point on, the ABS warning light would reset and go out with a restart. When we got home I brought the truck to Ford and they said there were no codes and all checked out to spec. Just chiming in and wondering if there might be any correlations? This has only happened on the last trip and the light has NOT come on since.

BTW: We love this truck and am in no way dissapointed!!
[img]/ubbthreads/images/graemlins/warmsmile.gif[/img]
Ted and Cindy

beetruck · 11-18-2006, 08:55 PM

when I took the truck to ford they found no codes but whys the light on I asked
no response they just replaced the senor the first time I took in

motorofficer · 11-19-2006, 11:56 AM

Strange coincidence. On the Interstate yesterday, realized that I had not yet checked out the cruise control to see if it worked. Put the cruise on for 70 mph, ran with it about 20 miles then had to take it back off due to traffic.

About 30 miles later, the speedo. dropped from 65mph down to 45mph then back to 65 mph. ABS light came on and didn't go out. Remains on even after re-start.

Checked the fuse in the distribution block, looks ok. More than likely it is the VSS. Going to contact the dealer first thing in the morning to see if I can get it in for repair.

My question is this.
Headed to Ocala this Friday for a camping trip pulling the 5th wheel. (see sig.)
If by chance I can't get the truck in for repair, would it still be ok to tow? I realize that the truck will "default" back to regular braking, but was wondering if it will have any effect on the integrated braking system while towing? [img]/ubbthreads/images/graemlins/shrug.gif[/img]
(Haven't updated my sig., truck now has 2300 miles)
Thanks in advance.

beetruck · 11-19-2006, 02:43 PM

yep that happens

Cody315 · 11-20-2006, 08:19 AM

[ QUOTE ]
My question is this.
Headed to Ocala this Friday for a camping trip pulling the 5th wheel. (see sig.)
If by chance I can't get the truck in for repair, would it still be ok to tow? I realize that the truck will "default" back to regular braking, but was wondering if it will have any effect on the integrated braking system while towing? [img]/ubbthreads/images/graemlins/shrug.gif[/img]
(Haven't updated my sig., truck now has 2300 miles)
Thanks in advance.

[/ QUOTE ]

Also recently had the same problem while towing my 12K trailer down the east coast. I could drive about 200 miles or around four hours before the ABS light came on. I would then pull over to the next rest area and when things cooled down (it seemed) all would be back to normal for another few hours or so....made for a long trip. I did notice however that while the ABS light was on, the bar graph indicating trailer braking power was not (or did not seem to) act as it should. Sometimes it did not light at all even though I would have thought it should have under the circumstances. Perhaps it was my imagination, but I don't think the trailer brakes were working correctly, if at all, while the ABS light was on. I would very much appreciate a diesel tech letting me know if this was all in my head or if indeed there is a problem with the trailer brakes and the ABS light being on and tied to the integrated brake system. When the ABS light was on I could manually activate the trailer brakes, but I'm glad I didn't have to do any panic stops. Techs, any input would be greatly appreciated. Will be taking truck in for a service shortly and have them check for any codes.

In short motorofficer, I think my trailer braking was affected when my ABS light came on.....hopefully it was just my increased paranoia rather than a real problem, but perhaps be careful just in case.

djshum · 11-20-2006, 06:41 PM

If your vehicle is an 2005, I would pull the speed sensor out and inspect the gap between differential housing and excitor ring. I have seen many that have partially worked there way off of the housing, causing ABS codes. Will set a P0500.

beetruck · 11-21-2006, 03:08 AM

yeah your right Cody315 when the ABS light comes on the trailer brakes don't work well at all I told Ford this they didn't believe me that I'm just a @^$*(*$( at least that's what I feel from them I've been told not to come back there too [dumb shop manger] One time I had to stop and I could feel the trailer push while I was trying to stop when the ABS light was on
I was told trucks made after march 19 2005 the brake controller was changed to something else not like my truck was made in Jan 11 2005 its not safe when you can stop when there a trailer pushing you dumb ford shop manger and they think they know every thing cause they didn't know about the trailer brakes don't work when your travel under 40km

boatbumm · 11-21-2006, 08:43 AM

if the ring has worked its way off the carrier and the gap is wrong then what ? and what will keep it fromj happening again if you press it back on ? my truck is out of the 36k warranty and i have already bought 2 of these $75 sensors and a pig tail and its starting to act up again ????? it is a 2005 and while under 36k the dealer put in a new carrier assy with new ring and pinion as my pinion nut had come loose and ruined everything. [img]/ubbthreads/images/graemlins/shrug.gif[/img]

djshum · 11-21-2006, 11:07 PM

There is a tsb on this...it instructs to remove cover and reseating ring using hammer and brass drift. Ford claims they were not properly seated at factory. I have done several of these and not had a problem after reseating excitor ring.

motorofficer · 11-22-2006, 10:15 PM

Ok, here's the scoop.
Just picked the truck up from the dealer this evening after repair.

The ABS light was due to the VSS. Tech. replaced the sensor.
Unfortunately, the repair order doesn't show the code that was stored.

Spoke to the service writer about towing the 5th wheel and if this problem should occur again. He did confirm that the brakes would default to "normal" and there shouldn't be a problem while trying to brake with the 5th wheel.
Hopefully he is correct, and I won't have to make any panic stops! [img]/ubbthreads/images/graemlins/shocked.gif[/img]

BTW, Cody: Where are you in SW FL?