Brake Light Stuck On

[wiggledbits]

04 11S ABS
I just got through replacing the brake lines. (I did this on my 04 GS no problem but if you can get the Galfer kit it is more complete. The Speigler kit for the 11S didn't come with pretty new Banjos) While there I re-wrapped the crumbled wire shielding where needed. The flush took extra flushing to get the last stubborn bubble out of the front (almost 1 & 1/2 liter). I tried to keep the lever pulls with in the normal range but I am sure I exceeded that range a little a few times. While wrapping the wiring I was careful not to yank and pull and tug excessively. While doing the flush I used contact cleaner and electric grease on the ABS harness plug.That is what changes where made prior to the problem.

What I believe is a symptom of the stuck brake light is the servo will not initialize and I get the fast flashing of the ABS light. It will blink and tick like normal for 2 flashes then go to the fast flash. So I think this narrows it the front brake because as I remember it the front brake has to be released for the system to test. This problem did not happen immediately. I can only assume that when the servo didn't kick on the brake light was on without the brakes being applied. I noticed the servo didn't kick in every time on key on after the change and attributed it to a weak battery. At start/on cranking it dipped below 10v. I know how this system likes its' juice. New battery bought and installed. I have checked the rear and no rocks or dirt so it seems to be functioning OK.

I can hear the ticks at the micros for front and back. I used contact cleaner and WD40 at the front switch. At the switch all looked clean, wires intact but I am tempted to replace the switch until I saw the $60 price tag. Seriously BMW $60 for a $6 part?!
Questions;
Where would you look next?

Am I chasing the wrong thing. What else in addition the the switch should I look at? Just seems like a HUGE coincidence to go bad after the flush but stanger things have happened.

Did my OCD on the ABS harness plug screw the pouch on this?

I am not a wiring guy so how can I test the micros. I will check the rear even though I think it is the front. I pulled the front switch to make sure it wasn't binding mechanically.

Is there an alternative front switch someone know of?

Right now I am looking for the fuse location for the ABS and for the connector at the end of the switch assembly. After that I don't have thoughts on where to go next short of a new switch.

Thanks.

[Groceryrun]

Did you bleed all the fluid circuits on the ABS unit and refill the ABS unit ?

[wiggledbits]

Originally Posted by Groceryrun

Did you bleed all the fluid circuits on the ABS unit and refill the ABS unit ?

Yes. All circuits bleed and refilled. I had it on the road everything working, plastic back on and of course filled the fuel tank. Then the ! light came on like the tail light was out. I had a problem with my LED Gizmo light and have since changed it to an OEM bulb. Is there any logic in the system for the brake light to stay on if there is an issue? Right now the ! goes out, brake light on, no servo power up.

I used the BMW Integral ABS Systems Flushing and Bleeding 101 from IBMWR I think as a reference. Like I said did the exact same on the GS without issue.

If I hold in the front brake on my IABS 04 GS and start it I get the same fast flashing and no servo power until I let the brake lever out. The rear has no effect.

[Groceryrun]

Start with the simple stuff first.

Remove the rear brake bulb. Look in the brake bulb socket and see if the contacts are in good shape.
All three contacts have to be in good shape and making contact with the bulb.
You can test the two filaments of the bulb with a VOM (voltmeter ohm meter ) or battery .

[wiggledbits]

Originally Posted by Groceryrun

Start with the simple stuff first.

Remove the rear brake bulb. Look in the brake bulb socket and see if the contacts are in good shape.
All three contacts have to be in good shape and making contact with the bulb.
You can test the two filaments of the bulb with a VOM (voltmeter ohm meter ) or battery .

yep did that all are clean and clear no shorts. If I remove the bulb I get the ! gen warning light, replace the bulb it and ! goes out after a few seconds as it should. Brake light still on and no servo startup. Time to find some needles I guess. If the brake switch was stuck (gate closed)to brake on I should see some current otherwise no current?

[brentw1]

both bulbs need to be good. it checks and gives a error,
do the servo motors run from the switches being opened?

[wiggledbits]

Both bulbs? Do you mean filaments. If so yep bright as can be. The gen warning ! light goes out. It is the ABS light that stays on 4Hz fast flash. I have pulled the front micro switch and no servo with switch lever pulled off the little button and grounded.

[wiggledbits]

Well it isn't the micro switches. Checked both and 4v relaxed 0 when depressed. Opposite of what I thought it would be but...

[brentw1]

is the fluid level in both secondary resevours on the abs unit full?

[BigDav]

I don't know anything about the system but it sounds like a connection or controller problem. The connection being more likely.

[wiggledbits]

Originally Posted by brentw1

is the fluid level in both secondary resevours on the abs unit full?

If you are talking about the front and rear Yes both are full to the top of the plastic finger. Maters are in the middle of min/max.

[wiggledbits]

Originally Posted by BigDav

I don't know anything about the system but it sounds like a connection or controller problem. The connection being more likely.

I have some time today to go back through it all. Since it was intermittent to start I hope it is just a lose connection some place. I even checked the ABS wheel sensor gap and both are in the middle of the tolerance.

[HarrisBikeNut]

I recently replaced the lines on my 2003 BCR and couldn't get the ABS to work. It was the same problem - brake light on constantly. Doing it outside during the day meant I never noticed. My local dealer sorted in in a few minutes! Cost me £70 including picking the bike up and returning it. You live and learn......
Bob

[brentw1]

no I mean the resevours on the abs unit.
there are 4 resevours on this abs system

[wiggledbits]

Originally Posted by brentw1

no I mean the resevours on the abs unit.
there are 4 resevours on this abs system

Yes. If by 4 it is the circuit reservoir and the ABS module. Here is the procedure I used on the GS and S. GS no problems. Pian in the butt but not too complicated. Like I wrote earlier after the flush all was good, self test, and braking.

http://advwisdom.hogranch.com/Wisdom/service_abs3.pdf

[brentw1]

ok just check that the resevours on the abs module are full there are sensors on them.
otherwise time to use a gs911 or the like.

[wiggledbits]

Originally Posted by brentw1

ok just check that the resevours on the abs module are full there are sensors on them.
otherwise time to use a gs911 or the like.

They (front and rear reservoirs) are up to the top of what looks like a white plastic divider so I am pretty confident they are full.

I am going to put it back together after tearing some stuff apart to check the front micro switch and check connections along the way. But for the ABS it has but the one large connectors that I am aware of.

Yep I was thinking that today. Debating buying one or taking to the shop to have it diag'ed. If I go GS911 will it give me more detail than ABS failed self test which I already know?

I will post back once I find out what the fudge the problem is.

[brentw1]

levels sounds right, make certain the two electrical connectors that plug on the
top of the resevours are fully on, they are the level sensors,
then the large connector of course,
the gs911 functionality is detailed on thier web site for each model.
as I rember it it allows you to run the servos from the gs911 to purge and bleed them.
if you get one probaby the wifi one.

[wiggledbits]

So my servo is back to working and break light working as it should. Huh! I did put the switches back and covered the tape warping with that plastic woven wire covering stuff (looks much nicer). While I was at it made side all connections were secure. I'm thinking I don't trust it going error on me just when I need it. I saw a USB GS911 with 2 or 3 VINs used on fleabay so I though if I could save a hundred or so bucks it would be worth the wait of 3 additional days. Weather has been crap anyway with cool rain. Dang thing went for almost $40 more than a new one shipped. Bet the seller was happy to use it for a few years and turn a profit. Ordered a new one yesterday.

[wiggledbits]

Just in case someone searches on here for the same problem I have tracked my original issue to the connector for the controller. Once I lock it in place I have to give a little downward pressure to apparently fully seat it. All pins are good and straight, seems I have the male and female part on the high and low end of the tolerances. If after seated I pull up on the connector I do not get an error as if it was disconnected. So at least I have some confidence that it will not vibrate loose and disable the servo just when I need it. GS 911 only showed a low voltage error from the dying battery.

Next issue...
While trying to find the original problem I accidentally introduced air into the front system. :-) I had the brake lever unit off the clip-on upside down to remove the micro switch and pulled the lever injecting air. Yes I know! Now I am failing to get that bubble completely out. Been through more than a liter and a half of BF, flushing the whole front system, used a back massage vibrator (no i didn't steal the GFs vibrator) on the lines and reservoirs, I have seen a few 3 or 4 very small bubbles come out after 4 or 5 MC fills and flushes but some still remain apparently since I can pull the lever in almost half way before any real pressure is present with ignition off. I am thinking I will put it back together less the plastics and ride it around the neighborhood to see if it'll break loose the air. I have a bicycle street with speed humps before and after every intersection so maybe a few wheelies and stoppies will bust the bytch loose. :-)

They way I see it if the air was injected into the system from the front lever MC I need to flush the whole system from what "they" call the front wheel circuit and control circuits. IE use the funnel on the reservoir to flush thru both calipers and then flush from the MC thru the 3 circuits. I have read that it can be a pain to get air out of the system but even replacing the lines wasn't this much of a problem.

Any more suggestions.