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disel dan
11-01-2002, 05:04 AM
Have 99 quad cab 24 valve diesel 2500 2wd.<br>Suddenly the abs warning lights were on.<br>Brakes are fine and function fine.<br>How can I diagnose the trouble.<br><br>Thanks<br>Andrew

11-01-2002, 05:10 AM
welcome to DTR disel dan, <br><br>my abs light and brake light have been on since I took my rotors/hub off to get the rotors turned. There is a speed sensor on both front wheels that plug into the hub. When I was installing the rotor/hub back onto the knockle I could not get this senor back into the hub and get it tighted down. <br>I don't know how mant other sensor or where others might be. Other members will jump in and help you out.<br><br>My abs and brake light has been on for about 6,500 miles so far.

disel dan
11-01-2002, 05:24 AM
I understand that if the lights are on then the brakes are defaulted into standard and not actually good for non skid conditions.

11-01-2002, 05:36 AM
I understand that if the lights are on then the brakes are defaulted into standard and not actually good for non skid conditions.


that is correct.
On mine I also have to push the pedel further to the floor it seems like.

disel dan
11-01-2002, 09:19 AM
Can anyone in tech on this forum help with any diag. on abs lights?

Lary Ellis (Top)
11-01-2002, 10:14 AM
Dan Here is some information on diagnosing your problem. This information is relevent to my 96 model I am assuming it may still be the same in your's. Anyway it should give you a place to start.<br><br> First make sure the parking brake is not on, then look over the hydraulic system to be sure it isn't leaking.<br> Make sure the brakes, calipers and wheel cylinders are in good condition.<br> Check the electrical connections at the control module assembly. The module is under the center of the dash. You can see it after you remove the knee bolster.<br> Check the fuses.<br> Follow the wiring harness to the speed sensors and brake light switch. Make sure the connections are tight and the wiring is not damaged.<br> If you don't find a problem you can output the stored trouble codes in the ECM. The RWAL data link connector is clipped to the underside of the knee bolster. a black plug pointing toward the floor to the left of the steering wheel.<br> Using a short jumper wire momentarily ground out terminal 13 (the black wire terminal) of the diagnostic connector and watch the amber abs warning light on the dash board.<br>Fault codes will be displayed by a long flash, followed by a series of short flashes count the short flashes after the long flash and compare with this chart.<br><br>1. Not used<br>2. Open isolation valve wiring or bad control module<br>3. Open dump valve wiring or bad control module <br>4. Closed RWAL switch<br>5. Over 16 dump pulses generated in 2wd vehicles (disabled in 4wd)<br>6. Erratic speed sensor reading while rolling<br>7. ECM fuse pellet open, isolation output missing, or valve wiring shorted to ground<br>8. Dump output missing or valve wiring shorted to ground<br>9. Speed sensor wiring resistance (usually a high reading)<br>10. Sensor wiring/resistance (usually low reading)<br>11. Brake switch always on, RWAL light comes on when speed reaches 40mph<br>12. Not used<br>13. ECM phase lock loop failure<br>14. ECM program check failure<br>15. ECN ram failure<br><br> Hope this points you in the right direction. If all this is gibberish to you then have a qualified technician look at it. Most likely a loose wire or bad connection you can find on your own when tracing the wires.

11-01-2002, 10:26 AM
Well said Mr. Top ;D

Outrider
11-01-2002, 10:40 AM
Also pull rear end cover off and inspect rear guts,plus pull ABS sensor off the top of rearend inspect thoughly.Why do I say this?I use to own a CTD and drove about 5000 mile with no spider gears and ABS light on.Pull the rearend cover off :o I have the pieces if you want to see them.But not the truck.<br>Warchild no longer among the living.

Lary Ellis (Top)
11-01-2002, 10:48 AM
<br>Also pull rear end cover off and inspect rear guts,plus pull ABS sensor off the top of rearend inspect thoughly.Why do I say this?I use to own a CTD and drove about 5000 mile with no spider gears and ABS light on.Pull the rearend cover off :o I have the pieces if you want to see them.But not the truck.<br>Warchild no longer among the living.<br><br> Assembles Honor Guard and Fires 21 gun salute over Warchild

Lary Ellis (Top)
11-04-2002, 02:32 PM
Dan let us know if you found the problem, we sort of like keeping up with our patients ;)

BigBlackDodge
11-04-2002, 03:48 PM
I bet Outrider hit the nail on the head :)

Straight6Jeff
11-07-2002, 02:15 PM
One other thing to keep in mind on the 2wd, if you unbolt the front shocks and let the suspension hang at full droop, be sure to move the abs harnesses before you unbolt the shocks. they are routed directly between the ball joint and upper frame. both harnesses were cut in half about 6&quot; before the sensors. A little solder, Heineken and shrink wrap, everything was functional again.

Jetson
11-07-2002, 03:34 PM
I would like to know if the truck has 2 wheel ABS or 4 wheel ABs. Could make a difference...