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Discussion Starter #1
Noticed yesterday while driving that 'low brake fluid' and 'ABS inoperative' lights were on. DSC was inoperative also and the DSC light is permanently on, with the switch being 'dead'. A 'Tyre control' message came up, all within a very short space of time, all interlinked I suspect.

Checked brake fluid level this morning and it is spot-on, so I'm baffled.

Any ideas would be very welcome? :dunno:
 

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I am a bit stumped aswell. Brake fluid level sensor maybe but would a faulty sensor throw the other lights on?
 

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when the brakepads-brakedisks are almost on there last legs you wil get a check low brake fluid warning. after a while it will be; check brakelinings and dsc/abs will be inactive.
dsc/abs is the first thing that wil disconnect because off safety issues..iff you count on the dsc light and it doesnt lid up because it cant interpolate good anymore when your brakes are almost gone,you could go over the edge off being safe in corners for instance.so thats why it gives a signal its disconnected.so you'd be aware its doesnt work no more.(in theorie dsc will still work, but not like it should)

iff it was a abs sensor it would be ;dsc off-abs light on.thats all

tyre control i dont know...because i dont have that feature.:hihi::hihi:

so my guess is your brakepads are almost gone.
 

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Discussion Starter #5 (Edited)
OK

Did some investigation this weekend - Saturday.

Checked brake pads and they are ok.

Checked brake fluid level and its ok.

So on Saturday I continued to be mystified.

Sunday I start her up and would you believe it - no warning lights WTF.
 

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It is a bit baffling; other than the explanation of brake pad wear which causes a few of the lights, I'm not sure - and you've checked them anyway. Have you checked your tyre pressures? In case by coincidence you got a marginal brake pad warning followed by a genuine tyre defect warning. Strange that all the warnings have disappeared though.

Maybe your little gremlin has moved from the stereo to the warning lights - how is the stereo now? Hope you get to the bottom of it anyway (hope it ain't expensive).cherrsagai
 

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Noticed yesterday while driving that 'low brake fluid' and 'ABS inoperative' lights were on. DSC was inoperative also and the DSC light is permanently on, with the switch being 'dead'. A 'Tyre control' message came up, all within a very short space of time, all interlinked I suspect.

Checked brake fluid level this morning and it is spot-on, so I'm baffled.

Any ideas would be very welcome? :dunno:
DSC combined with a tire pressure warning is almost invariable a wheel speed sensor.

Our tire pressure system measures difference in wheel rotation to determine a flat (smaller diameter). DSC functions on the same principal - if a wheel is spinning faster / slower than the rest then it applies the brakes to correct.

The common ingredient? The sensor in the wheel (called a pulse generator I believe) that tells the systems how fast a given wheel is spinning.

Can't for the life of me remember how to narrow it down to which wheel...

d-
 

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Discussion Starter #8
It is a bit baffling; other than the explanation of brake pad wear which causes a few of the lights, I'm not sure - and you've checked them anyway. Have you checked your tyre pressures? In case by coincidence you got a marginal brake pad warning followed by a genuine tyre defect warning. Strange that all the warnings have disappeared though.

Maybe your little gremlin has moved from the stereo to the warning lights - how is the stereo now? Hope you get to the bottom of it anyway (hope it ain't expensive).cherrsagai
The M5 was designed to baffle and it does a good job.

Stereo never bottomed, but it is going through a well-behaved phase (about 3 weeks since it misbehaved). It definitely is better behaved in warm weather, or is it drier weather?

Next time it lets me down , if I have a bit of time, I will use the info that Doug Baker kindly provided to track down the cause.
 

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there is probably a fault code stored.
iff it could be a wheel/abs sensor there will be a code for sure.. on the gt1 it even says witch one on witch side.

i had to replace the right front one a year ago, but only dsc/abs lights came on for that,nothing else.only had the problem when it rained, once dry for a couple off days and it was all good again.
(my problem came up after cleaning the wheels with a wheelcleaner/acid kind off product, and some off that liquid leaked in somewhere or so with the following problem..thats what i always thought/suspected, offcourse not your problem,to be clear :haha:)

also when you checked your brakepads did you check the brakepad cables to?? i mean the cables where the brakepad sensor is on..maybe that is damaged and took some water or so and triggered something?

just wild guessing...:3:


strange problem you got there hmmmhmmm

hope you find it..good luck mate.
 
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