ABS INOP - No Codes, Did A Search
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I read 3 pages of ABS INOP threads and they did not help much. I recently changed the front pads with hawk hps, they didn't seem that great, then after a week the light came on. Here's what I can tell you -
Only the ABS light is on and it stays on. Sometimes it takes about 30 seconds after I've started the car for it to come on. I have not been recently towed, dyno'd or had the car up in the rear (have yet to check rear sensor, though). I did check the wheel hub sensors in the front, they are on snapped in fine. Fuses are fine, I ordered a relay and should be here soon. Fluid level is fine. I recently deleted the cruise control module and cable a few weeks prior to the light coming on. I scanned it with an Auto X-Ray EZ Scan 3000, and got no codes. And my brake performance doesn't seem as good as it could be.
If I took it to a shop, would they be able to diagnose it or would they just throw parts at it?
Only the ABS light is on and it stays on. Sometimes it takes about 30 seconds after I've started the car for it to come on. I have not been recently towed, dyno'd or had the car up in the rear (have yet to check rear sensor, though). I did check the wheel hub sensors in the front, they are on snapped in fine. Fuses are fine, I ordered a relay and should be here soon. Fluid level is fine. I recently deleted the cruise control module and cable a few weeks prior to the light coming on. I scanned it with an Auto X-Ray EZ Scan 3000, and got no codes. And my brake performance doesn't seem as good as it could be.
If I took it to a shop, would they be able to diagnose it or would they just throw parts at it?
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Took it to a shop for diagnosis, they said the ABS brain is bad. I thought I knew exactly what that was but looking up parts I see ABS Control Module, ABS Actuator Kit, and ABS Modulator. Which is it? Also he told me when I do brake jobs to open the bleeder screw when I compress the piston, I've never touched it, what does he mean?
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The module is the brain, the actuator is the moving parts (hydrualic valves and solenoids) and the modulator could be either or both?
He means when your pads are thin there's a lot of fluid behind the piston. If you compress the piston back into the caliper the fluid goes back into the master cylinder passing the hydraulics. There's a chance that any impurities in the fluid will eventually get caught up in the hydraulics and foul it up. I've heard many techs say this to me but I've never seen it happen and I don't open the bleeders very often when doing this. So in order to avoid the potential to screw up expensive actuators you would open the bleeder screw on the caliper before forcing the piston back in. This way the old fluid just flows out of the system instead up back upstream. Any trash in the fluid (if it's that bad you've got other brake problems) will no longer pose a threat to the ABS.
Vernon
He means when your pads are thin there's a lot of fluid behind the piston. If you compress the piston back into the caliper the fluid goes back into the master cylinder passing the hydraulics. There's a chance that any impurities in the fluid will eventually get caught up in the hydraulics and foul it up. I've heard many techs say this to me but I've never seen it happen and I don't open the bleeders very often when doing this. So in order to avoid the potential to screw up expensive actuators you would open the bleeder screw on the caliper before forcing the piston back in. This way the old fluid just flows out of the system instead up back upstream. Any trash in the fluid (if it's that bad you've got other brake problems) will no longer pose a threat to the ABS.
Vernon