bouncing speedometer...RABS? [Archive] - PowerStrokeNation : Ford Powerstroke Diesel Forum


PowerStrokeNation : Ford Powerstroke Diesel Forum > F-250 & F-350 1986-1997 & Other Ford Trucks > 1994-1997 Power Stroke Technical Info > bouncing speedometer...RABS? PDA bouncing speedometer...RABS? 96centurion 04-17-2008, 06:50 AM Hi all, I have been chasing down a bouncy speedometer for a little while and I am running out of Ideas. SYMPTOMS: speedometer has an irregular bounce that seems to start around 30-40 mph and the bounce seems to be progressively worse the higher the speedometer reads, all the way up to when it is pegged :pullover: Here is what I have tried so far: Replaced VSS 2 times. Replaced Instrument cluster. Neither of these have worked, what else should I look for? I am not sure if the RABS (rear abs) module is tied into the speedometer or not, anyone know? Anyone else have this problem before and been able to fix it? Thanks in advance. Carl Madvan 04-17-2008, 04:32 PM The ABS uses the same vss/dss as a input. Its wired parallel with the PSOM Have you tested the wiring (+/-) and vss/dss signal to the cluster? Being that you have no problem with the ABS, i would believe from the tone ring to the ABS input harness splice would be good. Bill 96centurion 04-18-2008, 09:12 PM I haven't tested voltage, could you give me a little help with the procedure? I don't have a clue:doh: I also forgot to mention that once in a while I will get an ABS light. If it comes on it will usually be after about an hour or more of highway driving and then it will not go off until the truck is shut off. No codes. I have not noticed any problems with the ABS, but I don't think my brakes could lock the 36x15.5 tires anyways:D dieselthrash 04-19-2008, 12:16 AM I haven't tested voltage, could you give me a little help with the procedure? I don't have a clue:doh: I also forgot to mention that once in a while I will get an ABS light. If it comes on it will usually be after about an hour or more of highway driving and then it will not go off until the truck is shut off. No codes. I have not noticed any problems with the ABS, but I don't think my brakes could lock the 36x15.5 tires anyways:D Mine does the same thing.Please keep us posted on what you find. racehauler 04-21-2008, 04:09 PM Pull the sensor out of the rear end and clean it off. There is probably a bunch of "fuzz" on the bottom of it. The sensor is magnetic so the minute shavings from gear wear will stick to it.