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I just bought a 1999 K1200LT. The previous owner told me that the reverse does not work. When trying to start it with a dead battery the starter got stuck and the starter would engage when ever the battery was connected. When I tried the reverse, the bike started to back up. I tried the trick where you disconnect the negative terminal on the battery and hold the starter button down while re-connecting the negative wire. This worked and the starter relay “un-welded” itself and now the starter button works great and the bike starts up. But now when in reverse the starter button seems to do nothing. Please help me get the reverse working again.
 

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Wrencher Extraordinaire
2005 K1200LT
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If your try on reverse was during the time the relay was welded - then that is why it worked. I highly recommend you replace the relay as it will now weld itself much easier and will not be reliable.


Now on to reverse. How it controls the starter motor. In forward the start signal (from the button) goes through one of two micro switches on the reverse control, passes through the reverser contoller (large silver box under the seat on the left side) and then goes to the starter relay which powers the starter. In reverse the same signal goes through the second switch on the reverse control and into the reverser controller. The reverser controller then feeds high current 12V directly to the starter motor. There is a tie point behind the battery where the starter motor wire(black), the wire from the starter relay (black) and the wire from the reverser controller (black/yellow) all tie together.

There are three large black/yellow wires that come out of the reverser controller. One goes to the battery (+), one goes to ground (the other tie point behind the battery) and one goes to the starter tie point. Make sure they are hooked up correctly. Often when replacing a battery the one that goes to the (+) terminal is left off. Even though they are all Black/Yellow the ends are marked as to where they go.
 

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jzeiler said:
If your try on reverse was during the time the relay was welded - then that is why it worked. I highly recommend you replace the relay as it will now weld itself much easier and will not be reliable.


Now on to reverse. How it controls the starter motor. In forward the start signal (from the button) goes through one of two micro switches on the reverse control, passes through the reverser contoller (large silver box under the seat on the left side) and then goes to the starter relay which powers the starter. In reverse the same signal goes through the second switch on the reverse control and into the reverser controller. The reverser controller then feeds high current 12V directly to the starter motor. There is a tie point behind the battery where the starter motor wire(black), the wire from the starter relay (black) and the wire from the reverser controller (black/yellow) all tie together.

There are three large black/yellow wires that come out of the reverser controller. One goes to the battery (+), one goes to ground (the other tie point behind the battery) and one goes to the starter tie point. Make sure they are hooked up correctly. Often when replacing a battery the one that goes to the (+) terminal is left off. Even though they are all Black/Yellow the ends are marked as to where they go.
John,
I also have a reverse inoperable problem on my 01LT (94K). I replaced the reverse controller and that did not work (so I put the original one back in).

In Sept 09 Dave Shealey commented "Sounds like an electrical break in the safety switch circuits. Have you done any testing on the reverse switch on the side of the transmission? It is behind the reverse knob. There are two micro switches in it and the plastic tips can get damaged if it is ever removed, causing one of the switches to stop working."

See attached pictures. Are these the micro switches you and Dave are talking about?
The reverse light on the dashboard comes on when I activate the reverse knob, so I thought the switch was ok.

How would you test for "an electrical break in the safety switch circuit"?

My next step was to try another reverse controller. Do you think that would be the problem?

Thanks so much,
 

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Wrencher Extraordinaire
2005 K1200LT
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13,942 Posts
Yes Dan those are the switches. The easiest way to test them is find the four pin connector along the left rear sub frame rail. Four wires, Pair #1 Brown/Red and Brown; Pair #2 Brown/green/yellow and Brown/green/white.

Use a meter and check continuity at the pairs. In Forward one pair will show continuity and the other will not. Then select Reverse and the pairs will swap continuity. I can't remember which is which but if they don't change, there is your fault.
 
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