ABS Three lights

[Kit]

I was doing a long run up to North Wales from Cornwall when after 70 miles the ABS lights came on.
Stopped at Exeter and on restarting no lights great then after 5 miles back on,on my next break the same thing happened. The next day the same happened did about 60 miles and the lights came on. Little runs 15 miles to work then back after work no lights at all.
A chap at work has a tester to tell me the fault codes so as to tell which wheel sensor is duff, hopefully thats the problem. But he did mention that that could fix it for a few weeks and return because of some ring or something lost me a bit at that point.
Seems the long drive I did the week before at 60 mph no lights 70 mph plus ish ;-) the lights come on?

 

[gookah]

On the Z4, the pressure switches under the brake master cylinder can give rise to these lights too. Unplug them, spray some contact cleaner in them and then plug back in. See if that does anything. Also too much brake fluid in the master cylinder can cause the lights to come on. Simple and free checks first

 

[Kit]

Well got this chap at work with a professional ODB2 reader cost him £1500 to look at the codes and it turns out to be one of the pins on the ABS module so he reset the codes and I will clean the pins this weekend.
Asked him about too much brake fluid in the master cylinder but he said he didn't think so.
But will clean those plugs as well, seems I'm there. @gookah

 

[gookah]

I was not convinced about the brake fluid reason either, but apparently it can have an adverse effect on those pressure switches at the bottom of the master cylinder.
The pressure switches accurately monitor how much pressure is in each circuit, and can spot an imbalance. That is one of the faults that can set the warning lights.
Too much fluid can affect the readings, because the fluid in the switches has limited space to go after releasing the pedal, causing very short term residual pressure in one or both of the switches, and hence a resulting imbalance and associated warning lights.
Shortly after getting my wife's Z4, I changed the brake pads, pushing the brake pistons back I had the master cylinder go full but I didn't notice until I had the lights come on.
Took some fluid out and the fault has never reappeared.

One to watch for in future.

 

[ppavuk]

Could be that, but i've had only two lights https://zroadster.org/threads/amber-handbrake-and-dsc-light.13003/