# Audi ABS wheel speed sensor Q (b5) **URL:** \ **Category:** Shift518 Automotive\ **Created:** [March 13, 2010, 4:38pm UTC](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902 "2010-03-13T16:38:57Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![maxwell](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/maxwell/32/6524_2.png) [@maxwell](https://forums.speedlife.net/u/maxwell)\ **Post date:** [March 13, 2010, 4:38pm UTC](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902/1 "2010-03-13T16:38:57Z")
[http://www.audiworld.com/tech/wheel45.shtml](http://www.audiworld.com/tech/wheel45.shtml) Backstory… Wayne and I just did the wheel bearing of my B5 A4 today. Unlike the above tech article the wheel speed sensor did not have a 5mm bolt holding it in place, it seems it is pressed in with no bolt. After fussing with it for a bit, we decided to leave the sensor on the knuckle and disconnect the clip from under the rear seat. Most likely we marred the face of the sensor when messing with it, as my ABS and brake light are now on in the dash. Simple question… is my brake light supposed to flash when an ABS sensor is bad? Everything seems perfectly fine on the car in terms of braking, although I have yet to apply enough brakes to induce skidding. That flashing brake light on my dash is annoying, just making sure I shouldn’t recheck my parking brake cable or something stupid. Thanks again to Wayne for his help… and no worries on the ABS sensor… that fucker needs replacing anyways! ---
**Author:** ![6SPD\_S4](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/6spd_s4/32/6326_2.png) [@6SPD\_S4](https://forums.speedlife.net/u/6SPD_S4)\ **Post date:** [March 13, 2010, 4:44pm UTC](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902/2 "2010-03-13T16:44:30Z")
GermanPSI has this same problem with the disco lights on the dash with his b5 a4 also. Im sure he will chime in. ---
**Author:** ![maxwell](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/maxwell/32/6524_2.png) [@maxwell](https://forums.speedlife.net/u/maxwell)\ **Post date:** [March 13, 2010, 4:46pm UTC](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902/3 "2010-03-13T16:46:13Z")
yeah that was a long OP… basically I want to know if the flashing brake light AND the abs light come on when the sensor goes bad… or should I be looking deeper into this. Peace of mind I guess… … that stubborn sensor is gonna get replaced soon. ---
**Author:** ![GermanPSI](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/germanpsi/32/6353_2.png) [@GermanPSI](https://forums.speedlife.net/u/GermanPSI)\ **Post date:** [March 13, 2010, 4:49pm UTC](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902/4 "2010-03-13T16:49:59Z")
Abs module is bad. Sounds very weird though to have it happen after u messed with it. But if u broke the sensor only the abs light would be on ---
**Author:** ![maxwell](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/maxwell/32/6524_2.png) [@maxwell](https://forums.speedlife.net/u/maxwell)\ **Post date:** [March 13, 2010, 4:50pm UTC](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902/5 "2010-03-13T16:50:32Z")
ps… Waynes the man! I prolly would’ve ended up cutting the damn sensor cable off if it wasn’t for him! ---
**Author:** ![maxwell](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/maxwell/32/6524_2.png) [@maxwell](https://forums.speedlife.net/u/maxwell)\ **Post date:** [March 13, 2010, 4:51pm UTC](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902/6 "2010-03-13T16:51:03Z")
> [@cell phone pictures](https://forums.speedlife.net/t/cell-phone-pictures/30117/21): > > Abs module is bad. Sounds very weird though to have it happen after u messed with it. But if u broke the sensor only the abs light would be on THE fuck? details? ---
**Author:** ![GermanPSI](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/germanpsi/32/6353_2.png) [@GermanPSI](https://forums.speedlife.net/u/GermanPSI)\ **Post date:** [March 13, 2010, 11:24pm UTC](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902/7 "2010-03-13T23:24:10Z")
> [@memorial day weekend pics.](https://forums.speedlife.net/t/memorial-day-weekend-pics/30122/4): > > THE fuck? > > details? When you have the abs light on and the brake light flashing this means your abs module is bad. If the sensor in the back where you did the wheel bearing was bad it would just throw an abs light and not a blinking brake light also. ---
**Author:** ![maxwell](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/maxwell/32/6524_2.png) [@maxwell](https://forums.speedlife.net/u/maxwell)\ **Post date:** [March 14, 2010, 7:52am UTC](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902/8 "2010-03-14T07:52:06Z")
> [@OK. who's the smartass.](https://forums.speedlife.net/t/ok-whos-the-smartass/30126/18): > > When you have the abs light on and the brake light flashing this means your abs module is bad. If the sensor in the back where you did the wheel bearing was bad it would just throw an abs light and not a blinking brake light also. Yeah, I did some research on it last night. Not too excited about it, but I should be able to have it rebuilt by any number of companies for pretty cheap. The thing that has me very confused is why it went at the SAME time we did the right rear wheel bearing and sensor. It just seems really odd that it happened at the same time. Lastly, based on what I’ve read I will be just fine without repairing the module, I just won’t have ABS. Can you confirm this? Any long-term negative effects from letting this simmer for a while? (with the exception of that ANNOYING flashing light that is) ---
**Author:** ![Wayne64SS](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/wayne64ss/32/6365_2.png) [@Wayne64SS](https://forums.speedlife.net/u/Wayne64SS)\ **Post date:** [March 14, 2010, 9:15am UTC](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902/9 "2010-03-14T09:15:11Z")
Doesn’t make sense it’s throwing a code for a bad ABS module. If I were you I would disconnect battery, pull back seat, and recheck that connection where we unplugged it. check to make sure maybe the wires didn’t get half pulled out of the connector while it was swinging around in the press etc. either way at least unplug it and check the connection under the seat there. That’s the only thing we touched, maybe its somethign super simple. Doesn’t make sense the module is bad all of a sudden. Anyway when your done plug the battery back in and fire it up, see what happens. I know you mentioned you were having some electrical gremlins anyway. Just seems funny to me after all we touched was that harness that you get a bad module. ---
**Author:** ![6SPD\_S4](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/6spd_s4/32/6326_2.png) [@6SPD\_S4](https://forums.speedlife.net/u/6SPD_S4)\ **Post date:** [March 14, 2010, 9:42am UTC](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902/10 "2010-03-14T09:42:34Z")
Yeah Chris has had those lights on in his a4 for a year and a half. no biggie. I think he is going to do the same thing as far as sending out the abs module to get fixed. ---
**Author:** ![GermanPSI](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/germanpsi/32/6353_2.png) [@GermanPSI](https://forums.speedlife.net/u/GermanPSI)\ **Post date:** [March 14, 2010, 9:45am UTC](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902/11 "2010-03-14T09:45:33Z")
Yeh I’m just saying that when the brake light blinks and and light is on the abs module is bad but do agree with Wayne that’s it’s really strange that it happened right after you did the wheel bearing. Doesn’t really make sense ---
**Author:** ![Wayne64SS](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/wayne64ss/32/6365_2.png) [@Wayne64SS](https://forums.speedlife.net/u/Wayne64SS)\ **Post date:** [March 14, 2010, 10:08am UTC](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902/12 "2010-03-14T10:08:18Z")
def bro, not disagreeing with you on the light meaning the module’s bad, just saying it don’t make sense. I’d dick with the connections we touched again before ordering a module. ---
**Author:** ![GermanPSI](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/germanpsi/32/6353_2.png) [@GermanPSI](https://forums.speedlife.net/u/GermanPSI)\ **Post date:** [March 14, 2010, 10:30am UTC](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902/13 "2010-03-14T10:30:41Z")
But then again you could leave that sensor unpluggged and it should only thow an abs light not a blinking brake light ---
**Author:** ![Wayne64SS](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/wayne64ss/32/6365_2.png) [@Wayne64SS](https://forums.speedlife.net/u/Wayne64SS)\ **Post date:** [March 14, 2010, 10:40am UTC](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902/14 "2010-03-14T10:40:31Z")
hmmmmmmmmmm that not a bad idea either…!! ---
**Author:** ![88slowmarro](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/88slowmarro/32/6339_2.png) [@88slowmarro](https://forums.speedlife.net/u/88slowmarro)\ **Post date:** [March 14, 2010, 11:16am UTC](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902/15 "2010-03-14T11:16:39Z")
orrrrrrrrrrrrr take it somewhere and have the system scanned ---
**Author:** ![underboosted](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/underboosted/32/6424_2.png) [@underboosted](https://forums.speedlife.net/u/underboosted)\ **Post date:** [March 14, 2010, 11:24am UTC](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902/16 "2010-03-14T11:24:15Z")
If the sensor is grounding out it could be making the light blink. ---
**Author:** ![88slowmarro](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/88slowmarro/32/6339_2.png) [@88slowmarro](https://forums.speedlife.net/u/88slowmarro)\ **Post date:** [March 14, 2010, 11:25am UTC](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902/17 "2010-03-14T11:25:49Z")
what is geounding mean ? i have heard of grounding out and what not .but the fuse could be tripped a pad sensor could be tripped and so on ---
**Author:** ![underboosted](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/underboosted/32/6424_2.png) [@underboosted](https://forums.speedlife.net/u/underboosted)\ **Post date:** [March 14, 2010, 11:29am UTC](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902/18 "2010-03-14T11:29:46Z")
Lol. I’m on my phone at work. Fuckin small buttons FTL. ---
**Author:** ![Wayne64SS](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/wayne64ss/32/6365_2.png) [@Wayne64SS](https://forums.speedlife.net/u/Wayne64SS)\ **Post date:** [March 14, 2010, 12:02pm UTC](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902/19 "2010-03-14T12:02:41Z")
this didn’t have pad sensors in the rear. ---
**Author:** ![88slowmarro](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/88slowmarro/32/6339_2.png) [@88slowmarro](https://forums.speedlife.net/u/88slowmarro)\ **Post date:** [March 14, 2010, 12:04pm UTC](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902/20 "2010-03-14T12:04:26Z")
ok , if the sensor is shorted it may pose the same problems though [Next page](https://forums.speedlife.net/t/audi-abs-wheel-speed-sensor-q-b5/250902.md?page=2)