markymark 0 Posted December 9, 2004 About every 20 jouneys the yellow ABS light stays on. I think that this is to do with low pressure in the ABS system??? Anyone know if this is serious? Does it need to be checked? If so, How much to check and / or repair? Does it really matter? cheers Quote Share this post Link to post Share on other sites
dr_mat 0 Posted December 9, 2004 Most likely a wheel sensor. Serious? No, the brakes still work, but you'll be able to lock the wheels now. Checked? Yes. Otherwise... Cost? Just reading off the error code is cheap. Fixing it depends what's wrong! Does it really matter? How annoying is the yellow light? If it comes on during the MOT it's a fail. Quote Share this post Link to post Share on other sites
pablo_vr6 0 Posted December 9, 2004 plus you have no ABS while the light is on! Quote Share this post Link to post Share on other sites
dr_mat 0 Posted December 9, 2004 I'm pretty sure I mentioned that in point 2, pablo... ;) Quote Share this post Link to post Share on other sites
pablo_vr6 0 Posted December 9, 2004 i thought it was worth stressing :D Quote Share this post Link to post Share on other sites
aclwalker 3 Posted December 14, 2004 At my last MOT, my VR6 failed on rear brakes. I was not surprised as the pistons were quite obviously seizing. I've never done the brakes on this car before and was in urgent need of an MOT so I got the guy to do it. However, he broke my ABS. I had never seen the light come on since I had the car, and the ABS worked perfectly. From the day of the repairs to pass the MOT, the light would come on at exactly the same motorway speed. Now it is on constantly. I keep meaning to have a quick look, as I doubt the sensors broke coincidentally that day. I've been told it's likely to be either dirt on one of the sensors or a loose "ABS cage". I think this is a perforated wheel which breaks a beam of light which the sensor picks up while the wheel is turning. If the wheel locks then this is detected by a lack of, er, beam breaking. I've never got round to fixing it yet but I'm hoping it's quite easy. I'm interested but not surprised to hear that if the light comes on during the test then it's a fail. What I did notice a while back, however, was that the last time my spoiler blew its fuse (does this about once a year), the ABS light went OFF. It turns out it's the same fuse for the spoiler as for the ABS warning light (and probably other warning lights). Question is, if the ABS warning light wasn't working would it be noticed that the car has ABS that is not working? Do they actually test for function of the ABS system? Or is it just a test for a lack of fault warnings? Quote Share this post Link to post Share on other sites
dr_mat 0 Posted December 14, 2004 It's not a light beam, it's a magnetic sensor that picks up the position of the metal cage by induction. That's why it's so robust. It's likely that he damaged the cage though. And other people have reported wheel bearings as being a cause for this type of thing too. (Vibration at high speed.) The MOT testers are *supposed* to check that the ABS light comes on with the ignition for four seconds then goes OUT, and STAYS out. Therefore a "blown bulb" is a fail... But as usual, YMMV. Quote Share this post Link to post Share on other sites
