BMW Luxury Touring Community banner

1 - 9 of 9 Posts

·
Registered
Joined
·
62 Posts
Discussion Starter #1
Hi everyone, I am asking this question on behalf of a fellow LTer who is touring Wales at the moment, he has had the breakdown/recovery service out to him because the ABS lights started to wig wag and when he turned off the engine the ABS pump was running and only stopped when he disconnected the battery. The mechanic traced the earth wire from the ABS control unit and cut it this stopped the pump running and the brakes work fine ABS lights still wig wag though. It's a 1999 has this happened to any one else? I searched the site but could not find a reference to this problem. Looking forward to any advise I can pass on. Cheers Bren
 

·
Registered
Joined
·
989 Posts
Are the brake light switches working correctly? That is, does your friend see the brake lights come on then he activates hand or foot brake?

A busted or misadjusted switch would make the ABS system confused.
 

·
Registered
Joined
·
62 Posts
Discussion Starter #3
Hi RD thanks fo your reply evidently he did have a brake light switch sticking on, he thought he had cured that but possibly not.
Cheers
Bren
 

·
Wrencher Extraordinaire
2005 K1200LT
Joined
·
14,093 Posts
That unit has an internal relay that is most likely stuck. It is under the big black housing.
 

·
Registered
Joined
·
62 Posts
Discussion Starter #5
Hi John I also thought that the relay had stuck but the breakdown mechanic cut the earth wire to the ABS unit and this stopped the pump running, so I don't think the relay has stuck. Cheers Bren
 

·
Wrencher Extraordinaire
2005 K1200LT
Joined
·
14,093 Posts
Airportech said:
Hi John I also thought that the relay had stuck but the breakdown mechanic cut the earth wire to the ABS unit and this stopped the pump running, so I don't think the relay has stuck. Cheers Bren
Since this relay is IN this unit, cutting the earth will stop the motor from running but power is still being applied to the motor through that relay. Anyway with the earth cut, you will now have normal brakes just no ABS function.

If you want to return to full function - tear into it and replace the relay. And reconnect the earth. It could also be the electronic controller that has gone bad as well causing the relay to stay on. It is not really a pump but a motor that operates tiny pistons to modulate the brake pressure in the lines.
 

·
Premium Member
Joined
·
1,882 Posts
fyi
this is exactly how my '99 ABS went. I never bothered to fix it after the noise stopped, it brakes just fine.
 

·
Registered
Joined
·
62 Posts
Discussion Starter #9
Hi thanks for all your suggestions I will pass them on to the man, I suspect he will do what you have done Cooke and take the bulbs out of the panel- See you at Saltburn
Cheers
Bren
 
1 - 9 of 9 Posts
Top