ABS and Brake light came on

[OILBRNR]

Yesterday when I started her up, both lights stayed on.



Any ideas?

 

[samb]

abs lights

my done that and it was the speed sensor in the rearend,

 

[rob10858]

speed sensor. had two trucks and a dakota do the same thing. the dealer can try a reflash and some times it can cure the problem. were lucky that our dealer service tech usually will do this for free. but most dealers will charge about $35 to plug in and "diagnose" the problem. go ahead and have it replaced, from what ive seen after the reflash, the lights come back on after a day or so. hope this helps.

 

[Midnight]

Been there done that. Speed sensor for sure.

 

[FD5]

Would this also apply to the 1995 or would there be some other problem? Mine came on last week.

 

[Horseman1]

I had a similiar problem with mine about two months ago. The dealer replaced the rear sensor. Worked great since. The mechanic also said that some times metal shavings could andwould get on the sensor and cause the same problem. I suggest that you at least pull the sensor and clean before you clear the code.

 

[boonsur]

check the fuses

Sounds simple, but it happened on my wife's car (light stayed on). Replaced the blown fuse and never had another problem.

 

[sonorakitch]

Hi,



Boonsur is correct. Happend on my truck yesterday when I went to plug in the trailer. Both lights came on, wondered what the heck it was, and found out in a parking garage that afternoon I had no brake lights! Changed the fuse, and the light has come off.



Hopefully, this could be it. I never thought of checking them... maybe you haven't either.



~Chris

 

[OILBRNR]

Well, thanks all for the replies.



The fuse in the cab and under the hood are good, so I'd assume the sender.



Can these be cleaned? If not, how much are they to replace. I'm out of warrenty at this point.



Doesn't this sender also feed the speedometer? If so, why does it work but the ABS is not happy?

 

[OILBRNR]

Finally got around to putting in the new speed sensor ($30) and it did fix the problem. Took all of 5 min!



Still don't understand why the ABS wasn't happy, yet the speedo worked fine...

 

[whiteknight]

This information might be helpful in the future. I found this in my Hanes repair manual for the 1994 - 1996 trucks with rear wheel anti-lock brakes only.



When the ABS warning light comes on there is a diagnostic code stored in the anti-lock brake controller. To retrieve the code:

1. Find the RWAL Service Diagnostic connector, which is clipped to the underside of the knee bolster.

2. Usning a jumper wire, momentarily ground terminal #13 (the black wire terminal) of the diagnostic connector and watch the amber ABS warning light on the dashboard. Fault codes will be displayed by a long, followed by a series of short flashes. Count the long and short flashes and compare to the following chart for diagnosis:

1-Not used

2-Open isolation valve wiring or bad control module.

3-Open dump valve wiring or bad control module

4-Closed RWAL valve switch

5-Over 16 dump pulses generated in 2WD vehicles (disabled for 4WD)

6-Erratic speed sensor reading while rolling

7-Electronic control module fuse pellet open, isolation output missing, or valve wiring shorted to ground.

8-Dump output missing or valve wiring shorted to ground

9-Speed sensor wiring / resistance (usually high reading)

10-Sensor wiring / resitance (usually low reading)

11-Brake switch always on, RWAL light comes on when speed exceeds 40mph.

12-Not used

13-Electronic control module phase lock loop failure.

14-Electronic control module program check failure.

15-Electronic control module RAM failure.



After the malfuction has been identified and repaired, the codes can be cleared from memory by disconnecting the battery for 30 seconds.



My comments: This works on my 1996 but sometimes it takes a few tries to get it to display the code. (disconnecting and reconnecting the batteries, turning key off and on untill it reads the code.



thought this might help someone.

 

[whiteknight]

To add to my prevois post, it seems to work best if while the truck is still running after the light comes on, if you will short the pin the ABS light will display the code. Do this before even shuting off the truck.

 

[nwinters]

I just did mine a week ago. Didn't need to buy a speed sensor. I just pulled the old one out, cleaned it, put it back in, and all was well.



Nate