Brake lights on can't turn off

[dc10bill]

today the 2004 R1150rt on start up I got the rapid flashing of (4 per sec) with ABS & would not go out above the 5 MPH. turned around in driveway and back into shop. I disconnected both brake switches front & rear from wiring harness. brake lights still on! So I assume I have "wiring short" some where other than the sticking brake switch.

I jiggled/banged the front brake lever a bunch of times and had normal just for one time heard ABS pump run when front brake lever was pulled, run thats why I disconnected the front brake light switch first than rear when brake lights would not go out when Ign. is on!

With the brake lights on, I have discovered the ABS pump will not run and one gets the the rapid flashing of ABS light or failure of ABS. with the rapid clicking of ABS relay in fuse box. All fuses are Ok

Who has the wiring digrams of the brake system? Guess I'll have to "spring "for the Manual or CD-rom,
as front wires at switch are green/black stripe & Gray, out of connector white/blue stripe.

I have fuel tank off, all faring panels off, seat off/panel around instruments, etc. so bike is basically stipped, I looked and looked at the harnesses and have seen nothing why brake lights would stay on! Of coarse factory manual is of no help on this!

[omg1010]

Check out this one (22 megs) http://www.michaelmaloneyphotography.co ... agrams.pdf
And this http://www.bmwgsclub.nl/schematics/R115 ... ematic.pdf
And this http://r1150r.smugmug.com/photos/15908153-O.jpg

Best regards
Oliver

[iowabeakster]

The brake light switch circuits are different than most bikes. When the circuit is closed... the brake light is off... when the circuit is open... the light turns on.

I played with my bike, trying to help someone else troubleshoot a long time ago.

With the front brake lever...I found I could make the brake light turn on TWO different ways!!!

1. The electrical switch
2. Fluid pressure from squeezing the lever (after I had removed the switch and held it closed).

So it may not necessarily be electrical. If the ABS unit senses pressure...it will light the brake light...even with the electrical circuit closed. If it senses pressure during start-up... it will error.

I'm a little confused by your post...

I jiggled/banged the front brake lever a bunch of times and had normal just for one time heard ABS pump run when front brake lever was pulled, run thats why I disconnected the front brake light switch first than rear when brake lights would not go out when Ign. is on!

Make sure that the lever fully returns to it's resting position, when released. You also could have gunk plugging up the tiny bleed back hole in the reservoir...and not relieving the pressure...so the ABS unit thinks you are squeezing the lever... and will show error.

[sweatmark]

today the 2004 R1150rt on start up I got the rapid flashing of (4 per sec) with ABS & would not go out above the 5 MPH. turned around in driveway and back into shop. I disconnected both brake switches front & rear from wiring harness. brake lights still on! So I assume I have "wiring short" some where other than the sticking brake switch.

The BMW Integrated ABS (iABS) uses foot/hand brake switches that are normally closed (NC), meaning the switch's electrical circuit is connected until the switch is physically activated. The iABS computer has control of the brake lamp, and uses the change in brake switch circuit voltage (from +volts to open circuit) as signal to turn the brake lamp on. Your brake light is on because the iABS controller senses a fault somewhere, possibly related to a brake switch and its wiring, or possibly another fault detected by iABS (wheel speed sensor, fluid level, system voltage).

I jiggled/banged the front brake lever a bunch of times and had normal just for one time heard ABS pump run when front brake lever was pulled, run thats why I disconnected the front brake light switch first than rear when brake lights would not go out when Ign. is on!

With the brake lights on, I have discovered the ABS pump will not run and one gets the the rapid flashing of ABS light or failure of ABS. with the rapid clicking of ABS relay in fuse box. All fuses are Ok

If some amount of jiggling seems to help cure the iABS fault, then it's possible that your front brake switch wiring is damaged, thus preventing the iABS circuit check through NC switch circuit. We have plenty of information here about the R1150** problem of tight wire ties around the front subframe area, with broken wires as a result.

Who has the wiring digrams of the brake system? Guess I'll have to "spring "for the Manual or CD-rom,
as front wires at switch are green/black stripe & Gray, out of connector white/blue stripe.

I have fuel tank off, all faring panels off, seat off/panel around instruments, etc. so bike is basically stipped, I looked and looked at the harnesses and have seen nothing why brake lights would stay on! Of coarse factory manual is of no help on this!

The following table shows iABS wiring harness info for R1150R Roadster, but I'm pretty sure the color codes are same for your RT. I have the original Excel file somewhere and can check...

[dc10bill]

I want to thank all the members that offered suggestions and advice on my problem of ABS! Thats why I support this form! I sure do get my moneys worth!

The fault was bad rear brake mirco switch for the brake light! Thats why the brake lights stayed on with ABS flashing the 4 times per second. So ABS coun't test it's self.

Just previously I changed the footrest plate from one I got off ebay as my old had bend and crack. so I just naturally left switch alone that was on plate, turned out it had slight bend and didn't fully close when brake stop bolt hit!

Another lesson learned all plugs have to be connected for the ABS to test it's self! So don't ever disconnect any thing like the dumm a** I was thinking I will isolate problem by disconnecting the switches only made things worse!