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Procedure #1 for 1150 GS
Cliff notes version
Ground the Brown/Blue wire on the round diagnostic connector under the front seat (clipped to the airbox).
Hold down the ABS button, turn on the ignition (1 minute) turn off ignition, then remove ground wire.
Here's the long winded procedure:-
1. Pull the seat(s) off and find the Diagnostic Connector that is clipped to the airbox. Find a suitable jumper
wire that can be used to connect 2 of the pins in the connector (a paper clip, mini test leads, alligator clip leads).
Try not to bend, fold or mutilate the pins.
2. Make sure the ignition is off, then find in the diag connector the Brown/Blue wire Pin # 2 (ABS Re-set) and
the Brown wire Pin # 4 (Ground). Jumper them together. The connector positions are marked with VERY tiny
numbers on the backside of the connector (where the wires enter the connector). The backside also allows you
to look at the wires and see their respective colors, (just in case you want to verify the labels of the pic above).
3. Turn the ignition on, and push down the ABS button (on the left handle bar pod).
4. After about 1 minute release the ABS button, and turn the ignition off.
5. Remove the jumper connection and turn the ignition back on.
Now you should have two ABS lights flashing together, instead of them alternately flashing.
If not, try again but this time hold the ABS button down BEFORE turning on the ignition.