ABS & Brake Light "ON" Speedometer working sometimes
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ABS & Brake Light "ON" Speedometer working sometimes
I looked around on the forums and found a few topics on this but nothing conclusive. The other morning I started my truck and the ABS & brake light have been on since. The speedometer works at cruise but not under 35mhp or so.
From what Ive read on the forums it appears I may have a faulty sensor on the rear end. Brake Fluid levels are fine and the brakes still work as if nothings wrong.
Anyone have any experience as to how I change this sensor or determine if it is indeed the issue?
Is this called a speed sensor?
From what Ive read on the forums it appears I may have a faulty sensor on the rear end. Brake Fluid levels are fine and the brakes still work as if nothings wrong.
Anyone have any experience as to how I change this sensor or determine if it is indeed the issue?
Is this called a speed sensor?
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RE: ABS & Brake Light "ON" Speedometer working sometimes
I would concur that you have a bad rear wheel speed sensor.
I'd say replaced it. It is about $40.00 from NAPA and it takes about 5 minutes to change. It is bolted to the top of your rear differential and has a 2 pin connector plugged into it.
Basically it is a magnet that reads how fast thetone ring in the rear diff is turning and then communcates this info back to your PCM and the ABS and Spedometer (certain years) are both effected by a faulty sensor.
It is an extremely common condition on all Rams to have this sensor fail, especially if it has been '"Mudded, or used in water crossings".
Let us know if that fixes it for you.
I'd say replaced it. It is about $40.00 from NAPA and it takes about 5 minutes to change. It is bolted to the top of your rear differential and has a 2 pin connector plugged into it.
Basically it is a magnet that reads how fast thetone ring in the rear diff is turning and then communcates this info back to your PCM and the ABS and Spedometer (certain years) are both effected by a faulty sensor.
It is an extremely common condition on all Rams to have this sensor fail, especially if it has been '"Mudded, or used in water crossings".
Let us know if that fixes it for you.
Joined: Nov 2007
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RE: ABS & Brake Light "ON" Speedometer working sometimes
I had the samw problem on my 98 Ram 2500. I took it to a local mechanic that said the ABS computer was bad. I went to the junk yard and got another computer. This did not fix the problem. Then I found this post so I replaced the speed sensor. Both lights went out but now the speedometer stays at about 5 mph until I let off the gas and then it goes up to about 25. Any idea what else is wrong?
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RE: ABS & Brake Light "ON" Speedometer working sometimes
1= have the rear brakes been adjusted latley??
2=have you drivin in a lot of high water??
3=there may be a scanner to rwad the abs unit...
if they (drums) have not been adjusted, the rear cyl may be over extended causing a loss in pressure. it does happen.
(I do not know if you have drums or disk in the rear.)
my abs light engaged the other day. the strap that holds the massa cyl cover on was loose.. so I has to drimp the darn thing a bit snugger. if it happens again, Ill get a new massa cyl (life time warranty-its a replacement)
2=have you drivin in a lot of high water??
3=there may be a scanner to rwad the abs unit...
if they (drums) have not been adjusted, the rear cyl may be over extended causing a loss in pressure. it does happen.
(I do not know if you have drums or disk in the rear.)
my abs light engaged the other day. the strap that holds the massa cyl cover on was loose.. so I has to drimp the darn thing a bit snugger. if it happens again, Ill get a new massa cyl (life time warranty-its a replacement)
