abs light is on

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The abs can't trigger a code for air in the system. If the light doesn't come on until you move then you have a wheel speed sensor issue somewhere and being that you just did work on the front left I would start checking there for something amiss
 
At each one of the front wheels you have a brake fluid hose that runs to the caliper, you also have an electricial cable that runs to the front wheel assembly, thsi cable is for the wheel speed sensor...follow the cable and you will find the sensor. On 4x4 models I believe you have to remove the backing plate to gain access to the sensor.
 
I bet that your a 2wd ST......



I bet you BENT the bracket or hit the wire and moved something or got oil on the sensor..



Todd Z
 
Ricoa,

At an idle there is not an issue. This leads me to believe it is not a fluid issue but a mechanical one. I would also think you bent the bracket.

 
Coastiejoe,

At an idle there is not an issue. This leads me to believe it is not a fluid issue



If you are at an idle, and the vehicle is not moving there is nothing to detect by the sensor. The ABS light can only detect a malfunction when it sees the vehicle is moving but it is not getting a valid signal from one of the wheel sensors or there is a significant speed difference (when not braking). That certainly can be caused by dirt or fluid on the sensor and/or tone-ring.



I agree that it is more likely a bent sensor bracket...possibly even a broken sensor wire.



...Rich
 
The sensors may be clean but the tone-ring can be dirty. They should not have to even touch the tone-ring when they turn the rotors....The tone ring is molded into the rotors and cannot be removed or shifted.



It is possible that the sensor bracket could have gotten bent just a little, enough to not be getting a good magnetic signal. I don't know the precise measurement, but they there is a specific air gap distance between the sensor and tone-ring. Also, be sure the tone-ring is clean.



Be sure to check the wiring to the sensors to be sure that they are not cut, chaffed, or broken. In the end it could just be a bad sensor? If everything else is OK, I would lean towards a bad sensor?



...Rich
 
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If you had the rotors turned. There might be a bunch of metal shavings in the tone ring. Or the shavings fell off and stuck to the sensor.

The sensor is a hall effect. There has to be equal gaps in the tone ring for the sensor to read, also a specific sensor gap.
 
Eddie,

Good point. The tone-ring consists of precisely spaced, segmented magnets and could attract the metal shavings from turning the rotor, which could/would interfere with the clear magnetic pulses picked up by the sensor.



ricoa,

I hope that was your problem.



...Rich
 
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