Figured I'd start a thread of my own to chronicle this - I'll come back & update with progress & pics, though it might be a slow project. Partly this thread is to help me document things that I've looked at along the way.
Right now, the bike is laid up with all the plastics off (incl. headlight assembly) and it's been this way for about a week now. I've just not had the time to look at it. Today was different, so today I started to poke it with the multi-meter before life got in the way again.
Re-cap of the problems:
- LH headlight ground connector has melted (been riding around for a few weeks with it unplugged, but conscious that will spread the problem elsewhere & I'm needing light more now, so the bike is parked up until I cure it).
- Intermittently, the windscreen up limit switch hasn't worked, though occasionally it's been fine.
- once or twice, on very wet days, the neutral light has illuminated while clearly not in neutral (being ridden in 4th for example).
Wiring diagram from this thread has been printed: https://www.st-owners.com/forums/threads/st1300-wiring-schematic.90873/
Today, I got as far as:
- checking the yellow ground connector behind the RH headlight (fine)
- checking the earth connection from the LH headlight through to the frame "bridge" under the tank (fine)
- checking operation of the up limit switch (fine). Since this wasn't a problem I couldn't swap the upper/lower relays to test anything
- checked the headlight aim motor & RH headlight connector for signs of melting (fine),
- checked the horn connections for signs of melting (fine),
- noted that the "options connector" is pretty gummed up (black tar like substance). Tried to find my contact cleaner spray to no avail. Will test the LH headlight to Options connector ground path when that's cleaned up.
- checked LH headlight to side stand switch ground path for signs of melting & continuity (fine)
- checked radiator fan connectors for signs of melting (fine)
- checked fuel pump connector for signs of melting (fine)
- checked all cabling for signs of chaffing/rubbing on frame etc (nothing evident, haven't unwrapped anything)
- checked fusebox for signs of water ingress (fine).
At this point, the heavens opened up, and the bike is parked outside, so all electrical works are halted & the bike is covered up. Looks like only the options connector & main harness connector on the left side of the bike - both being heavily gummed up - need to be cleaned / checked.
As I've looked at the wiring diagram this evening, I think I've identified the root cause. A previous owner of my bike fitted non-weather-proofed USB connectors to the dash (on top of the dash) and wired it to take power from the main connector on the back of the clocks (positive from cluster illumination, negative on chassis ground). Looking at the diagram, I've learnt that this chassis ground is shared with the headlights (and headlight motor). I'm aware in the past that I've been charging my phone in the USB connection while riding in the rain a few times. I speculate that the increased load on the circuit (charging my phone + water) has fried the LH headlight connector ground (given I can't see anything else really wrong). This same ground connection is also shared by the up/down limit relays on the windscreen (and the options connector).
So, the plan of attack when I get the time:
- ask you guys if you have any other opinions on things to check/considerations in general
- find switch cleaner spray
- clean & check the main harness & options connectors on the left of the bike
- replace the H4 connectors (both) with new pigtailed connectors
- wire secondary earth point from the H4 pigtails to the headlight subframe to help mitigate the load issues (seems to be an intermittently reported problem across a number of owners)
- wire in the busboard fuses that I recently purchased (need to get a 100A 12V relay first)
- wire USB connectors to come from the busboard
- fit & wire in the stebel horn that arrived this week - will be connected to the busboard with a relay on the original loom
- run wires for future additional lighting (front & rear) with waterproofed connectors.
Should anyone have any thoughts on what to look for, thanks in advance, I'm all ears.
Right now, the bike is laid up with all the plastics off (incl. headlight assembly) and it's been this way for about a week now. I've just not had the time to look at it. Today was different, so today I started to poke it with the multi-meter before life got in the way again.
Re-cap of the problems:
- LH headlight ground connector has melted (been riding around for a few weeks with it unplugged, but conscious that will spread the problem elsewhere & I'm needing light more now, so the bike is parked up until I cure it).
- Intermittently, the windscreen up limit switch hasn't worked, though occasionally it's been fine.
- once or twice, on very wet days, the neutral light has illuminated while clearly not in neutral (being ridden in 4th for example).
Wiring diagram from this thread has been printed: https://www.st-owners.com/forums/threads/st1300-wiring-schematic.90873/
Today, I got as far as:
- checking the yellow ground connector behind the RH headlight (fine)
- checking the earth connection from the LH headlight through to the frame "bridge" under the tank (fine)
- checking operation of the up limit switch (fine). Since this wasn't a problem I couldn't swap the upper/lower relays to test anything
- checked the headlight aim motor & RH headlight connector for signs of melting (fine),
- checked the horn connections for signs of melting (fine),
- noted that the "options connector" is pretty gummed up (black tar like substance). Tried to find my contact cleaner spray to no avail. Will test the LH headlight to Options connector ground path when that's cleaned up.
- checked LH headlight to side stand switch ground path for signs of melting & continuity (fine)
- checked radiator fan connectors for signs of melting (fine)
- checked fuel pump connector for signs of melting (fine)
- checked all cabling for signs of chaffing/rubbing on frame etc (nothing evident, haven't unwrapped anything)
- checked fusebox for signs of water ingress (fine).
At this point, the heavens opened up, and the bike is parked outside, so all electrical works are halted & the bike is covered up. Looks like only the options connector & main harness connector on the left side of the bike - both being heavily gummed up - need to be cleaned / checked.
As I've looked at the wiring diagram this evening, I think I've identified the root cause. A previous owner of my bike fitted non-weather-proofed USB connectors to the dash (on top of the dash) and wired it to take power from the main connector on the back of the clocks (positive from cluster illumination, negative on chassis ground). Looking at the diagram, I've learnt that this chassis ground is shared with the headlights (and headlight motor). I'm aware in the past that I've been charging my phone in the USB connection while riding in the rain a few times. I speculate that the increased load on the circuit (charging my phone + water) has fried the LH headlight connector ground (given I can't see anything else really wrong). This same ground connection is also shared by the up/down limit relays on the windscreen (and the options connector).
So, the plan of attack when I get the time:
- ask you guys if you have any other opinions on things to check/considerations in general
- find switch cleaner spray
- clean & check the main harness & options connectors on the left of the bike
- replace the H4 connectors (both) with new pigtailed connectors
- wire secondary earth point from the H4 pigtails to the headlight subframe to help mitigate the load issues (seems to be an intermittently reported problem across a number of owners)
- wire in the busboard fuses that I recently purchased (need to get a 100A 12V relay first)
- wire USB connectors to come from the busboard
- fit & wire in the stebel horn that arrived this week - will be connected to the busboard with a relay on the original loom
- run wires for future additional lighting (front & rear) with waterproofed connectors.
Should anyone have any thoughts on what to look for, thanks in advance, I'm all ears.