I have a 99 F350 Crew Cab Deisel. The ABS light is staying on after I start it up and the speedometer doesn't register at low speeds. I get a flashing of the overdrive light on the shifter. I know the flashing light indicates a fault somewhere. Has anyone had this problem? Any suggestions on where to look for the problem? Is there a way to get the failure code without having to buy a scanner? Thanks snipped-for-privacy@ev1.net
ABS light on
Jan 05, 2004
10 Replies
Odds are great it is the speed sensor in the differential. Cheap part, easy fix - if you don't shear the bolt taking it off. Could also be in the wiring from the sensor, but I bet it's the sensor.....
Both your manual and you are wrong. It's on the rear axle. Period. Not on the R4100 tranny. On the axle.
8mm bolt. Drop the spare so you can get to it.
Now that I think about it might be a 10mm...take both under there with you. Stop by Ford and p/u the sensor....it's less than $20.00
You likely need a vss (vehicle speed sensor). Ford should have the part for around $20.
The vehicle speed senssor is in/on the transmission. The rear axle ABS sensor is in the differential. Since the symptoms also include a speedometer problem, I'd bet on the vehicle speed sensor, not the ABS sensor. If the VSS goes south, the transmission will show a fault, the ABS will show a fault, and the speedomter won't work properly. If the ABS sensor in the rear axle goes bad, only the ABS is affected.
Ed
bomar wrote:
Yep, the vss is what I replaced when the spedometer on my f350 wouldn't go above 0. It was on the rear differential. Look in the book.
My apologies. YOu are 100% correct. From the 1999 Service manual:
"Vehicle Speed Sensor (VSS)
"The VSS has been deleted for 1999. On vehicles equipped with 4-wheel anti-lock brake systems (4WABS), the vehicle speed signal is generated by the rear anti-lock brake sensor and sent to the 4WABS module. The
4WABS module sends the vehicle speed signal via circuit 679 (GY/BK) to all systems that require a vehicle speed signal input. Vehicles equipped with rear anti-lock brakes (RABS) generate a vehicle speed signal from the rear axle speed sensor. The generic electronic module (GEM) receives this signal (VSS_GEM) for internal use and then distributes it to the appropriate other users (i.e., the powertrain control module [PCM], speed control module, and speedometer)."Sorry for talking out of turn.
Ed
So no apology to me???? Wait and see if I ever help you again.......
Sorry, Please accept my apology.
Ed
bomar wrote:
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