fschiola

Last September I got the ABS and brake lights on my 2000. I replaced the WSS and everything was working ok until a few weeks ago they came on again. I've replaced the WSS twice since and no help. I heard that if there was a lot of metal in the diff it could cause problems so I replaced the fluid in the diff (nothing abnormal). I also replaced the brake fluid and the brakes feel better than they have for a while. The odd thing is that it dosen't come on until I go about 35 to 40 MPH and then stays on until the truck is restarted.

I was reading a list of fault codes for the RWAL and noticed that there is one #11 that says" brake switch always on, RAWL light comes on when speed exceeds 40mph"

Anyone heard of this and do you think replacing the stoplight switch will fix it?

I 've also seen in my manual that the switch has 6 terminals with #1 and #2 listed "for the RWAL/ABS module and PCM circuit"

Do you think the switch could be bad?

fschiola

I thought I'd let anyone who wants to know what I found out about my problem. After seeing that one of the trouble codes was for a stoplight switch failure, I looked in my Haynes manual and they had a test procedure for checking the switch. I took the switch out and when I tested it the results where the opposite of what was described in the manual. I also thought about the trailer brake controller and unplugged it and replaced the stoplight switch to take it to town to get a replacement. As I started to town, no ABS or brake lights on the dash and the cruise was working. Reset the cruise several times and it still worked great. So I pulled over and plugged the brake controller back in and everything still worked great. I went to the parts store and bought a replacement switch because I had to take the truck to Alamosa today and didn't want to get stuck with no part. I ran aprox. 260 miles and everything still worked as it should with the old switch. I think that maybe the contacts in the switch where dirty or glazed and working it full travel when I was testing it cleaned them up.

crobtex

I hate it when I buy parts and the problems fixes itself.
I'm glad it's working now and the info is a good reference post.

dawgo1

My truck has the brake and abs lights on , codes out 55 on the light. Any Clues???

fschiola

It would be helpful to know what year your truck is. If you could fill in your signature it would really help us to help you. In some years "55" means completion of fault code display. In otherwords there are no codes set. The ABS has to be scanned separately with DC's special scanner.

If you don't have 4 wheel ABS, replacing the rear wheel sensor corrects this problem about 95% of the time. I's a very easy repair.

dawgo1

Sorry, I guess the truck info didnt get entered, I will fix that. I feel like a real idiot now for asking about the code 55, I finally found my manual and looked it up and found just what you relayed! I cannot find the diagnosyic 16 pin connector though, I tore the whole dash apart! Any clues if a different one was used for the 1994 2500 4x4? JBody talked of a different one for the RWAL only but I have 4 wheel ABS. Any help would be greatly appreciated. I have an ELK hunt in October and need to fix this before hand!!!!!

J BODY

If you have 4WAL you need to communicate with a scan tool and that is dealer only for that system as far as I know.

dawgo1

Ok now here is a new twist. I just got back from towing a load of hay. On the way back the abs and brake lights did not come on until I was about 2 miles from home.
Could the rear brake adjustment effect the abs? I did have to back about 100 yards. Could this have made some difference..........I'm at a loss, I own a .45 auto, maybe its time to put the old girl down!

dawgo1

I had no idea that emoticon was on there until that post!!!!!!!! Now thats funny....I dont care who you are!

Dshiftff

I had this same problem up until friday. I have the 4WABS and my brake and abs light was on. Tested out the Wheel sensors right at the ABS module with an ohm meter in the engine compartment on the driver side fenderwell. They should Ohm out around 1400 Ohms. Using the main harness going into the ABS module, Use pins 1+14 to check the rear diff sensor, use 2+15 to check the Right front wheel sensor, use pins 3+16 for the left front sensor. I found the front right sensor out of spec, so I took it off and cleaned it up there was metal debris stuck to it and ohmed it out off the truck and it seemed ok, put it back on and the lights were off. I dont know if there was a bad connection or if the metal was interfering with it somehow, But for now all is good.

dawgo1

Thanks Dshiftff, I will try it. Any idea where the diagnostic connector is on the 94 ?
The manual says under the drivers knee bolster, not on mine!

Dshiftff

I dont know about the connector, but maybe someone else will come along.

88bird

i dono my abs and brake light have been on for over 6 months..... i have rwal it stops every time..... so i just covered the lights up with black electrical tape......

MNorby

mine has done the same thing too recently when pulling a trailer it seem (multiple trailers too). Get the brake and ABS light on my 97 and my turn signals and brake lights die (pops the fueses for them) I can replace the fuse and works ok for a while. Also my cruise hasn't worked for a couple months and have been looking into that tonight too now. Suppose it could be related to your problem?

dawgo1

Ok black tape and extra fuses!.........not quite the high teck approach but practical.
My abs and brake light have a mind of their own now, sometimes they go out for a while then come back on later, and sometimes only one will be on.....I guess even they need a break now and then.

Still looking for the diagnostic connector if anyone knows where it is?