Electrics in headlight
- Thread starter lavrat
- Start date
G
Grant
Guest
79 is BTZ ignition and associated electrics, so might be a diode, but you should have 2 of them.
Spade connector either end, one end marked 'battery' and the other marked 'generator'.
It's important otherwise why would they put it there...
Spade connector either end, one end marked 'battery' and the other marked 'generator'.
It's important otherwise why would they put it there...
D
dja981
Guest
As far as I know the idea of the diode is to stop power going to other electrical circuits when you put the ignition switch to position 2/park. Must get round to fitting one to my bike, said that every year since 1982.
Dave
Dave
G
Grant
Guest
Ah, must be a 1978 one then. It's a CDI type loom there. The diode is to stop the ignition being activated if you leave the ignition switch in Park position. So you may want to fit another one soon.
I guess they are available from the usual suspects, depends where in the world you are.
I guess they are available from the usual suspects, depends where in the world you are.
Dellortoman
Hero member
- Location
- Tasmania, Australia
Correct. It's a diode. There's only one of them. If you want to replace it, you can buy diodes at any electronics shop, but it won't necessarily look the same as what you have. You'll need one that will carry a couple of amps because it powers up the tail light, front parking light and instrument lights in normal running mode (when the ignition switch and headlight switch are on).
When the bike is parked and you want to leave the parking lights on, then the ignition switch is put in the park position which powers up the tail and front parking lights via another feed. The diode is to stop the parking light circuit back-feeding through the headlight switch. If the headlight switch is on, then it will feed back into the ignition system, which would allow the bike to be started. Not something you really want when the bike left unattended!
However. It's a bit like an appendix. You can get rid of it without any problems if you want to. Who ever uses the parking light function anyway?
Just take it out and reconnect the two wires without the diode. If you leave the parking light feed from the ignition switch connected, you can still use the parking light facility. Just make sure the headlight switch off, otherwise the ignition will come on. You may want to disconnect the parking light feed from the ignition switch just to prevent that possibility, but it isn't strictly necessary.
Incidentally, the factory wiring diagrams for the 750s and early triples show the diode arse about. They eventually drew it the right way around for the post 1977 triples. It disappeared altogether with the BTZ ignition bikes.
Cheers,
Cam
When the bike is parked and you want to leave the parking lights on, then the ignition switch is put in the park position which powers up the tail and front parking lights via another feed. The diode is to stop the parking light circuit back-feeding through the headlight switch. If the headlight switch is on, then it will feed back into the ignition system, which would allow the bike to be started. Not something you really want when the bike left unattended!
However. It's a bit like an appendix. You can get rid of it without any problems if you want to. Who ever uses the parking light function anyway?
Just take it out and reconnect the two wires without the diode. If you leave the parking light feed from the ignition switch connected, you can still use the parking light facility. Just make sure the headlight switch off, otherwise the ignition will come on. You may want to disconnect the parking light feed from the ignition switch just to prevent that possibility, but it isn't strictly necessary.
Incidentally, the factory wiring diagrams for the 750s and early triples show the diode arse about. They eventually drew it the right way around for the post 1977 triples. It disappeared altogether with the BTZ ignition bikes.
Cheers,
Cam
G
Grant
Guest
As I said, the CDI type loom has one diode, the BTZ has two diodes inside the headlamp shell, used for a different purpose no doubt. Not shown on the green book diagram I have.
I would be investigating the root cause of why it melted before bypassing it.
I would be investigating the root cause of why it melted before bypassing it.