The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: disco51 on August 12, 2016, 08:20:20 AM

Title: front brake pressure switch question
Post by: disco51 on August 12, 2016, 08:20:20 AM

Anyone have this fail on their bike?
When it fails, does it typically stay always on (brake light on) or always off (brake light won't work when squeezed).

Title: Re: front brake pressure switch question
Post by: Bob_Roller on August 12, 2016, 09:56:10 AM

I would say a common failure would be the Iight not coming on  when the brake lever is pulled .

You need to check the switch with a multimeter and see what what you get .

With the brake not applied the switch sbould be open, with the brake applied the switch should be closed .

Title: Re: front brake pressure switch question
Post by: Tony Smith on August 12, 2016, 06:53:27 PM

Quote

Anyone have this fail on their bike?
When it fails, does it typically stay always on (brake light on) or always off (brake light won't work when squeezed).

The experience of others may vary but I have head brake pressure switches fail "open" and fail "closed" so I would not express an opinion as to whether one is more likely than the other.

What I will say is that they are generally reliable, fail rarely and are easily and cheaply replaced.

Title: Re: front brake pressure switch question
Post by: disco51 on August 13, 2016, 08:44:04 PM

Tested the switch for continuity and it is faulty.
Of note, the pressure switch that snowbum recommends from Napa (SL 143) leaked like a sieve after install.  The depth seems to be wrong.  Ordered the OEM today.
Guess it will be time to bleed the brakes with some new brake fluid.
FYI, mine failed with the brake lights on continuously.