Brake pad sensor cheat - K-Bikes.com - Excellence in Motion
 
LinkBack Thread Tools Display Modes
post #1 of 6 (permalink) Old Dec 31st, 2014, 11:11 pm Thread Starter
Noob
 
Join Date: Nov 2013
Location: Cooranbong, New South Wales, Australia
Posts: 21
Brake pad sensor cheat

Front brake pads on the 06/07 K1200GT include one pad (the outside right) which has a sensor. The sensor activates the warning light on the instrument panel via the ECU software which unfortunately presents two disadvantages:
(a) To satisfy your bike's ECU software, you are precluded from using any pads other than those supplied only by BMW dealers Anything else, i.e. aftermarket, may well work fine but being rejected by the software results in the warning signal remaining on.
(b) No matter what you do, after changing the pads the bike has to go onto the dealer's diagnostic system to be ' reset'. This applies even if you use the appropriate BMW pads and fit them yourself (easy job and takes about 30 minutes) or if the dealer fits them.

The trick is to pre-empt the warning light by fooling the computer.
The sensor is a essentially a single wire which loops around a small plastic insulator fixed to the pad backplate adjacent to the pad itself but positioned so that it is in contact with the rotor and wears progressively alongside the pad. Once the rotor has worn the pad and the insulator down about 2.5mm (see attached pic) the rotor will ground with the wire causing a 'stage 1' warning signal. Another 0.5mm later the rotor cuts through the end of the wire loop turning it into two loose-end wires. The computer recognises the instant jump from zero electrical resistance to no circuit at all and on comes the stage 2 warning light which will not go out until a new pad/sensor is fitted and the system is reset.

The computer also goes into a Stage 2 warning mode the moment you disconnect the sensor plug from the terminal block.
Remove the right hand fairing panel because before you disconnect anything at all you will have to bridge the circuit in front of the terminal block. It's tricky in that the connection block twin terminals are small, deep in the terminal and on the end of a restrictively short section of wiring loom.
To make the bridge, I used a 40mm length of B (2nd) wire guitar string (high tensile stiffness but fine gauge) bent into a 6mm wide U-shape. Using nose pliers make sure the bridge wire is well positioned in contact with both terminals at the back of the terminal block because you get only one shot at this when you pull the plug. The price of failure is onto the dreaded dealer diagnostic rack. Also important, temporarily insulate the bridge in place with tape to prevent accidental grounding while you fiddle about.
The cheat is fiddly but effective. Do not disconnect the battery as that will actually cause what you are trying to avoid.
If you are happy to do without the brake warning (sensor) system so you can go for much cheaper aftermarket pads, cut the terminal connection plug from the worn out BMW pad leaving about 25mm of the two wires poking out. Twist and solder them together and insulate with a heat shrink sleeve.
Replace the plug into the terminal block and only then carefully remove the bridge wire. If you are fitting the correct new BMW pads, reconnect the electrics after fitment, check everything, and then remove the bridge.
I've just fitted new BMW pads and conned the computer which as you can see from the pic was getting ready for Stage 2.
Attached Thumbnails
Click image for larger version

Name:	brake pad sensor.jpg
Views:	267
Size:	797.2 KB
ID:	17185  

Last edited by Quickie; Dec 31st, 2014 at 11:18 pm.
Quickie is offline  
Sponsored Links
Advertisement
 
post #2 of 6 (permalink) Old Jan 1st, 2015, 10:51 am
Addict
 
Join Date: Mar 2004
Location: , , UK
Posts: 3,750
voxmagna is offline  
post #3 of 6 (permalink) Old Jan 2nd, 2015, 3:52 pm
Enthusiast
 
Join Date: Mar 2012
Location: Moyock, NC, USA
Posts: 357
Ummmmm... When you get the bike, simply unhook the little orange plastic piece from the pad and fold it back onto its own wire and zip-tie it.
No computer issues and you can use whatever pads you want.

------------------------------------------------------------------------------------------ Message sent from my Radio Shack TRS-80 using a keyboard and electricity.

Last edited by moymurfs; Jan 2nd, 2015 at 4:07 pm.
moymurfs is offline  
Sponsored Links
Advertisement
 
post #4 of 6 (permalink) Old Jan 5th, 2015, 8:37 am Thread Starter
Noob
 
Join Date: Nov 2013
Location: Cooranbong, New South Wales, Australia
Posts: 21
Brake sensor cheat

Logical idea but in Australia (probably different in the USA in this context) our insurance/traffic laws people tend to frown on original engineering alterations unless the alterations are certified and I've heard that bypassing the manufacturer's brake sensor simply to 'turn it off' to fit cheaper pads is something they won't accept. It can, apparently, also have legal consequences in the event of any accident subsequent to selling the bike or where there's a claim involved (doesn't even have to be brake related - any claim) unless you have already informed your insurer of the alteration in which case the insurance company will likely not issue the cover, retract your existing cover or charge you an excess big enough to fit 747 brakes to make the policy amendment.
Thus rather than take the risk, I fitted genuine pads just to keep the sensor system intact which mean't of course, I couldn't retain, or need, the old sensor. For me, the goal was to temporarily bypass the system to avoid going to a dealer just to switch the darn thing on.
Understandably, I did consider removing the insulator block and folding it back and for those owners looking to fit cheaper pads, it's probably the easiest option. In the USA, CL brake pads are $33 per side for the front v $90 for BMW - my the genuine Beemer front pads in Oz were $143 (sensored right pad set) plus $108 for the left).
The old pad was seriously worn and dirty (discouraging a detailed inspection) but it looked as though the sensor wire actually passed through the steel backplate which would have mean't cutting the wire irrespective thus making removal of the insulator block somewhat pointless. On closer inspection, the wire and insulator can be removed from the backplate but it is necessary to cut the shoulders off the insulator to do it (with careful use with a Dremel or similar) while the pad hangs out of the harness. As even a new connector block can't easily be refitted to the backplate later (no shoulders) I reckon it's easier to pull up the sensor wire sleeve and use mini alligator clips to make a bridge wire anywhere before the sensor (in this case it's not necessary to bridge before the connector block). Simply bare the wires (avoiding any earthing at all times) and remake the circuit loop anywhere in front of the sensor itself with a blob of solder joining the two wires, cut off the sensor, remove the bridge, and insulate as required. Takes about 20 minutes.

Last edited by Quickie; Jan 5th, 2015 at 9:18 am.
Quickie is offline  
post #5 of 6 (permalink) Old Jan 6th, 2015, 3:34 pm
Addict
 
Join Date: Jun 2008
Location: New York, NY, USA
Posts: 676
Are you paid by the word? Glad you have attained a resolution.

P.S. I'm not trying to be rude, I'm just from NY.

2008 K1200GT, Custom Paint, Vivid Black, Aeroflow WS & Aeroguards, Givi E52 Maxia Topcase w/AdMore Lighting, Zumo 660, Suburban Footpeg Lowering, Sargent Seat

2009 R1200GS Adventure, Magnesium Grey/Black, Adventure Cases, Zumo 660, Touratech Unobtanium Accessories

1974 Norton Commando 850 Soon to be a restoration project
lhendrick is offline  
post #6 of 6 (permalink) Old Jan 7th, 2015, 10:09 am
Enthusiast
 
Join Date: Mar 2012
Location: Moyock, NC, USA
Posts: 357
Quote:
Originally Posted by lhendrick

P.S. I'm not trying to be rude, I'm just from NY.
Classic!

------------------------------------------------------------------------------------------ Message sent from my Radio Shack TRS-80 using a keyboard and electricity.
moymurfs is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the K-Bikes.com - Excellence in Motion forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Thread Thread Starter Forum Replies Last Post
Fluid exchange on the 2006 k12S ABS Brake Servo peterpeter211 K12/1300GT (Next Gen) 1 Sep 16th, 2013 9:35 am
18K Service - How many hours? Captain K12R K12/1300R/R-Sport 8 Jun 17th, 2011 12:18 pm
ABS power Brake Problem Solved The Fllash Technical, Repair and Maintenance 2 Aug 7th, 2010 10:33 pm
The best way to brake K bikes TiMax K12/1300GT (Next Gen) 11 Sep 11th, 2008 2:01 am
BRAKE ! LED Fails After Software Update panhard K12/1300R/R-Sport 0 Jul 20th, 2008 5:09 pm

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome