Originally Posted by motoexplorer
Bike was only down for 4 days. My first thought was that maybe the battery was weak. I hooked it up to another battery and got the same behavior.
When I hit the starter button the headlight doesn't go out. It stays on. There were a couple of time I could hear the starter just start to turn over and then quit.
How do you diagnose the load shed relay and where is it at?
The load shed relay is normally closed (i.e., the headlight, etc. work). When the starter button is pressed, voltage is applied back up the load shed relay's trigger ground line, causing the load shed relay to open, killing the headlight. If there is insufficient voltage getting to the load shed relay, the headlight won't go off.
Your symptoms suggest that the starter relay is fried -- the voltage to the load shed relay is supplied from the *output* terminal of the starter relay. So, if the relay is dead, no matter how good the battery is, little-to-no voltage will get to the starter and the load shed relay.
My first question is: Does the bike have the updated starter relay and harness?
Early in the life of the LT, there were significant issues with the starter relay welding itself shut, so that the starter motor ran whenever the battery was hooked up. This condition was caused by trying to start the motor with a battery having to low a voltage (low voltage, very high current would cause the contact to arc/weld shut). While this is not exactly your problem, I mention it for the idea that the original starter relays were not great bits of kit; they can fail in a number of ways.
I'm afraid checking (and if this is the problem, remedying) this issue requires getting to the starter relay, which is in the electrical box under the gas tank.
See post #25 in this thread, and in particular the 3rd photo, for the start relay position:
The starter relay is the component in the upper half of the electrical box, on the lower level to the left.