No Speedo, Check Engine, Brake, and ABS lights on -- Fix

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aRBee4863

Junior Member
Military
Joined
Apr 1, 2022
Posts
23
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18
Location
Boise, ID
Ram Year
2005
Engine
5.7
Noticed the speedo slowly failing 6 months ago. It would kind of dance around and not read out until I reached 40-50 mph, and even then it was "iffy". Eventually, it went completely dead. Showed codes P0501, P1502. My troubleshooting over the course of the next couple months:

- Check the rear abs wheel speed sensor on the rear diff for metal shavings on it
- Check the wiring between the rear abs sensor pigtail and the abs control module
- Clean and inspect the connector at the ABS control module
- Replace the rear abs wheel speed sensor on the rear diff
Then I learned from the Hanes manual that my year's speedometer reading actually comes from the transmission Output Shaft Speed Sensor (OSS).
- Change the OSS
- Change the rear abs wheel speed sensor again and warranty the first one back to RockAuto

In the meantime, I changed my differential gears and installed a limited slip (Eaton TrueTrac) because they were making noise and getting stuck in the snow on the lightly banked shoulder is embarassing. Vain hope that this would solve the problem.

- Gave up and took it to the dealer. Diagnostics $130. Dealer calls the next day and says the problem is my Rear ABS Wheel Speed Sensor. Part $120, total $200 out the door for me was including labor(they knocked off the diagnostics fee since I had them do the work).

Problem solved. I've read this before on one of these forums while I was looking for the solution, but I think that rear speed sensor is a dealer-only part. No matter what Autozone or O'Reilly or Rockauto will sell you, it will not work.
 

Jbrewer5211

Junior Member
Joined
May 19, 2022
Posts
1
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0
Location
Tampa
Ram Year
2018
Engine
6.7L
Hey there,
Not being a gear head at all, where should I check for these locations? left side/right side on the rear? I am having the same issue and trying to do this before taking to my StealerShip here in Tampa.
 

Daw14

Senior Member
Joined
Nov 29, 2017
Posts
2,029
Reaction score
2,079
Ram Year
2014
Engine
5.7 hemi
Hey there,
Not being a gear head at all, where should I check for these locations? left side/right side on the rear? I am having the same issue and trying to do this before taking to my StealerShip here in Tampa.
Find a mopar dealer site ,go to parts and pull up your truck. You will be able to locate what you are looking for As there are parts diagrams .
 

Wulf

Senior Member
Military
Joined
May 16, 2021
Posts
182
Reaction score
77
Location
United States
Ram Year
2021
Engine
5.7 Hemi
Find a mopar dealer site ,go to parts and pull up your truck. You will be able to locate what you are looking for As there are parts diagrams .
Usually, yes, but sometimes no, or the "diagram" is of such a low quality that you cannot tell for sure if it is the item you really want or not.
 

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