Headlight Relay, I did search quite a bit.

So, I have recently torn off the Atari from my 81' Seca 750 and installed a round headlight + new speedo. The headlight was working while I have the front end wires dangling about but as soon as I 'carefully' crammed them into the headlight bucket and turned her over no headlight. I torn everything back down double and triple check the connections for loose, cut or miss matched wiring but everything looked good. No busted fuses so I thought it could be the headlight relay. Tested it by starting the bike and jumpering, I can't remember exactly which cables and the schematic is in the garage, and the light came on.

So, long story short, I need a new headlight relay and I don't want to pay $80 bones. I have the relay apart now and I'll try cleaning the connections and give that a go before diving in for a new one or figuring out a bypass. Are there any universal relays I can use in place of the OEM one? I ran across a post saying that a standard 30A will do but I would like some verification.


Any additional recommendations are appreciated.


Dane

 

Did you find this thread: http://xjbikes.com/Forums/viewtopic/p=274779.html when you searched?

What exactly did you jumper to determine that you needed a headlight relay? If you were jumpering in the headlight bucket to make this determination, then there are still a number of other things it could be.

A standard 30A relay will NOT do without some modification. Please review that other thread. If you really do need a new relay, I can give you the details on how to build one.

 

I did run accross it and it didn't register with my low firing synaps as some tests I should be doing to verify my hunch. I'll run the tests as soon as I'm done at the office. Sitting here is going to feel like an eternity when I could be at home working on the bike. Thanks for the reply, i'll report back with my findings.

 

Alright SQL life saver, I ran through two of the four steps.

1. Headlight on
2. Headlight on

In the previous post you said to stop here as the fuse box was the most likely culprit. I will search around the forums for some information regarding the fuse box unless you think I should head a different direction.

 

OK. Good information.

Your headlight relay sounds like it's good.

However, the other thread was a bit of a different situation. There are a couple of other things we should check on yours:

Connect the jumper between Red/Yellow on the relay and battery +, then start the engine. If the headlight comes on, the problem is almost definitely the fuse box. If it doesn't come on, then it could be the alternator, the plug between the alternator and the regulator/rectifier, or the diode block. Basically, this check is to see whether the relay is being triggered by the alternator as it should be.

 

Light came on when connecting res/yellow to positive battery.

 

And after you started the engine? Right?

OK. So that's the fuse or fuse box, then.

 

Yup after starting her up. Took a real close look at the head fuse and it was nice and corroded at the red/yellow wire. Looks like a new fuse box is in my future.

I greatly appreciate the help SQL Guy!

Is there anyway I could get the details on how to build my own relay, for future reference?

 

OK. Something like this should do the trick. Use a regular automotive relay and a 1A or better rectifier. The end of the rectifier with the band goes to terminal 86.

 

Awesome, thanks again! I temporarily re-wired the headlight fuse connection, removing the corroded conection and the headlight works. Thanks for taking the time to hlpe me, greatly appreciated.