Electronic Fault Finding

The 650GS has minimal electronics compared to other models. The electronics provide the functionality to reap the benefits in improved fuel economy and weight reduction but without the excessive complexity of other models.

There are only 3 electronic systems, ABS, BMSC, and Dash. The BMSC is the only programmable device with diagnostics capability limited to the ABS and BMSC plus the associated dash lamps.

It is worth considering that the total volume and weight of the BMSC engine electronics and sensors is less than 30% of the weight and volume of extra fuel needed in every refill if the electronics was not used.


Little is known about the electronics internal to either of the ABS systems on the 650GS, whether repair of the electronics is feasible is not known at this time. All of the information on the systems is in the Brakes and ABS page.


There are 3 variants of engine ECU. The first two, BMSC and BMSCII are made by Hella with a 3rd made by Magneti Marelli called the BMSE introduced on the 2013 model. Little is known about the BMSE and firmware at this time.

The engine sensors are the same between all models including G650X, details are on the Engine Sensors page.

The BMSC are comprised of a 5v Freescale 68000 processor and memory with 12v output stages for the fuel pump, 02 sensor, Fan and Tank Vent Valve. All program code, adaptions and fault codes are held in non volatile memory.

Faults in the output stages of the 00-04 BMSC are repairable but it is not for the feint hearted.

Warning. On EU models do not use the spare Tank Vent Valve socket under the seat to power accessories. This is a BMSC output and could generate fault codes or damage the BMSC, the current through it is monitored by the BMSC.

Information on the 3 BMS and details of the IC's used on each are in the pdf and zip files below.

2013+ BMS-E equipped models have fuel pump and fan relays mounted under the seat near the fuse box.

Also see Other Repairs and Utilities/Diagnostics for BMS firmware and TSB information.

It is recommended to fit an earth strap to the case of the BMSE on 2013+ models.

BMSC/E Resets

Resetting of the BMSC/E is only done via diagnostics, depowering the BMS does not reset fault codes or adaptions.

It is also an urban myth that twisting the throttle 3 times with the ignition on performs some form of BMSC reset.

Technical Service Bulletin 13 003 03 (051), at F650.com explains it & other relevant info. See the Reset Myths pdf

Component Replacement

When replacing a BMS sensor, Fuel Injector or Fuel Filter Regulator always reset the adaption tables with a GS911. There are variations between components and it is the adaption tables which adjust for these variations.

You can contact me if you have a failed ABS, BMSC or Dash Assembly.


The dash for all the models up to the 2010+ has two connectors, a 12 pin connector for the dash electronics (X9001) and a separate 10 pin connector for the dash lamps (X9028). All the dash lamps other than the Fuel Level and the ABS operate independently of the Dash electronics. PDF's with the dash pin outs for all the models is below. Fault finding for the dash lamps is a matter of multimeter testing from the dash X9028 socket. 00-09 Dash Info pdf

00-04 F Series
The instrument panel is subject to some problems with aging. The clock display mount is known to chafe the PCB plus dirt/corrosion near the input socket, causes failures, the 5v supply rail capacitor degrades. Clean & check periodically. Dash PCB Pics
05-07 F Series and 08-09 G Series
The instrument panel is subject to some problems with aging. There is a revised PCB with different firmware for F/G models. Aging or corrosion is causing failures, the 5v supply rail capacitor degrades. It is worth cleaning & checking periodically

Detailed Dash PCB Pics All Dash Connector Pinouts 00-09 Dash IC Info

2010+ G650GS Series Dash

Little is known about the Dash on these models at this time.
The firmware is not able to be updated and the capability of repairs is unknown.
More info will be added as it comes to hand. Dash Info Dash Plug Pinout

G650X Dash

The G650X dash is different to the 650GS, Advrider inmate Snooker, has information re the dash on his web site. The pdf here has some basic information on all of the G650X electronics G650X ECU Info pdf

Husqvarna TR650 Dash

The TR650 Dash is based on C Series scooter electronics but different in appearance.

The dash operation is very different to the 650GS/X as it relies on CAN BUS and EWS.

Cafe Husky has info on some repairs like broken buttons.

Fault Finding

The primary tool needed is a diagnostics system like the GS911, the basic diagnostics routines are held in the ECU's. Diagnostics tools simply activate test routines. Dash diagnostics is limited to some lamp testing.

The diagnostics routines in the BMSC/E are more extensive than the dash assemblies with component testing.

Once the fault codes are obtained then it is down to checking continuity of wiring from the ECU sockets to the sensors and output devices. Diagnostics routines can be used to continually trigger components while checking the continuity of the wiring. Resistance of components can also be checked from the ECU sockets.

Ensure all engine sensors are tested and confirmed operational before concluding a BMS is faulty. There have been occasions where dealers have replaced a BMS only to find the fault was a sensor, particularly the crankshaft sensor.

Real time values can be obtained from the BMSC to enable analysis of the operation of components. Output is in CSV (Comma Separated Values) format for input to a spreadsheet. The skill is in interpreting the results.

When fault finding with the ignition on, use a battery charger or power supply to avoid a flat battery