1999 abs brake problem

[tjgindy]

I was out baja-ing, and the next day my abs light was on. No abs brakes at all were to be working.. That was in September, on Christmas day the temp was like - 10 or something here in indy, I started the jeep up, and the abs light didnt kick on,,, so i tested the brakes out and sure enough they worked until about 500 ft down the road, and havent worked since.. so when it was really cold, they worked once. What is the major malfunction???

[Cam7]

IS both Brake Lights On? or is just the ABS Light On?. When You turn the key on you should be able to hear the ABS Motor run . Since you off roading you might have got dirt or crud built up in the calipers and wheel sensors you might try cleaning them. It is really hard to diagnost ABS systems without a Scan Tool with ABS capabilities. Also check make sure you didnt damage any hoses and brake lines and check fluid level.

[tjgindy]

Just the abs light is on. fluid level is good, I will try cleaning the brakes real good. thanks for the reply.

[Cam7]

If the light comes on before the car is in motion the problem is probally in the Modulator Pump ass. If it comes on while moving it most probally is a wheel sensor. Some of the ABS Parts have a lifetime warranty from Chrysler .

[tjgindy]

it does come on before the jeep is moving, when i start it, it comes on within 5- 10 seconds

[Cam7]

Your problem is most probally the Hydraulic Control Unit. It is hard to say with out a Scan Tool to diagnost the system. The system should have 2 Relays Main Relay and Pump motor Relay check those first. It is possible you could have a shorted wheel sensor the Values are 900-1300 Ohms. Other wise you will have to find someone with a Scan Tool that has ABS capabilty.

[xj31]

you definitly need to get the code or codes. you cant check those sensors with an ohm meter.they work completely differently from older ones.you actually need to test them for voltage output.back probe the sensors and you should have around 1 volt dc and it should change when you spin the wheel.resistance values are meaningless and can be misleading

[Cam7]

X is right about the values, your system is the Teves mark 20E different system than mine, Have to read the codes. Find someone with a good Scan Tool that will read ABS.

[myjeepsux420]

Check both wheel speed sensors on the front. They're on the axle before it enters the hub, or atleast mine is on my 1993. Clean them with some brake clean and see if the light does off.