bad relay problem...

[yamahansolo]

i am dumbfounded... i have a 79f and it keeps draining the battery. even with the key off and not in the ignition. i have a jump box can jump it off with so i have been using it to trouble shoot

now with the battery disconnected. i hook up the jump box and then the relay up by the ignition clicks. is this normal? it has i beleive blue, black red?white strip and maybe yellow?? i can disconnect it and no juice gets to the bike i thought this might be the rerve lighting unit relay but i am not sure. i unhooked the reserve lighting unit over by the rectifier and the relay still clicks when you hook both terminals to the bike with the jump box. also it does not seem to be charging good when it's running.

i drove the bike for a month or so with no problems. i did however try to hook up the horn and it did not work so i unhooked it and put everything like it was. i am stumped and i want to ride!

[yamahansolo]

also i forgot to mention... i tried a diffrent relay in the others place and it clicks just the same... i have been using the handlebar lock alot lately and i don't know if the po ever ues it... i have been searching. do yall think the ignition switch is stuck on??? the bike will shut off if i take out the key but the realy is still tripped. until i ull the battery terminals...???

[randy]

yamahansolo;

That relay is the headlight relay and it should only 'click' with the engine running. You may have a short in your wiring causing the relay to be fed 12V constantly.

Question 1: When the relay 'clicks' does the headlight come on?

Question 2: Have you re-wired anything lately?

[yamahansolo]

i have not rewired. and no the light does not come on it just clicks. but if i have the key in the ignition in the on position the light will be on until you try to start it... all the fuses are good and everything else seems on. i also forgot that i even unhooked the ignition switc. i unplugged it inside the bucket and the relay still clicks??? i did however try to hook up a horn that was not functional and i accidentally hit the valve cover a couple of times and got some sparks but it didn't blow the fuse...

[yamahansolo]

new update...

ok with the bike turned off... and the reserve lighting unit unplugged. and the ignition unplugged the yellow wire going to the headlight relay by the sterring head has 12 volts going to it...??? is this normal? i didn't think it would be.

do these bikes have the little plastic box that has some kind of coil in it so when the bike starts running the hyeadlight comes on? my 79 special 750 did. and it melted inside one time. but i didn't see one on this bike. my xj has what appears to be one but i can't find it on the 79s???

[John]

You need to check the yellow wire on the headlight relay, and see if it has voltage to it at all times. If it does, it will energize the relay, but because the igntion is off, there will be no power at the red/white wire that supplies power thru the relay, and then on to the headlight through the blue wire. When the ignition is turned on your headlight comes on...it shouldn't. It should only come after the engine starts, and the yellow wire is energized by the alternator. The red wire has power when the ignition is on, therefore the light will come on.

[yamahansolo]

i'm not sure i understand the lat post? right now should the yellow wire have 12 volts going to it? if it's not supposed to then that sounds like the short is somewhere back along the path of the yellow wire? correct?

[randy]

Right. The yellow wire gets voltage from the alternator and it should only have voltage when the engine is running. Somewhere a live wire is shorting to the yellow, energizing it.

To find the circuit that is feeding the short:

Key off.

Set your voltmeter to a DC range for 12V.

Remove the positive battery cable.

Connect the positve meter lead to the battery post and the negative lead to the battery cable. The meter will show the voltage drain.

One by one, remove fuses and when the voltage drain drops to zero, that circuit is the one with the trouble. Now you can trace that circuit through the harness.

P.S. That yellow lead is also connected to the tach for RPM input, but at the tach it's white. Good luck and keep us posted.

[yamahansolo]

thanks!!! just tried all that. i found some interesting stuff???


po had replaced the fuse box with a newbe. it's pretty close to stock as i have the xj sitting right next to it to compare... it appears the top brown, and red wires were backwards... my manaul says the top side is red brown brown brown and bottom is i forget but those look correct. mine had the brown wire being first and then the red wire. so i switched them back to normal and the reserve unit no longer clicks when you connect the battery. there still however is a 12 volt drain. i unplugged all 4 fuses and they still draw 12 volts from the battery while testing. also the accessory draws 12 as well. is there another fuse or live wire somewhere i am not seeing?


currently the reserve unit is disconnected, the key switch is disconnected.

[randy]

With the battery connected to the bike, one side of the fuses will be live all the time.

To test each circuit properly you have to remove the battery cable and insert the meter between the battery post and the battery lead.

Geez, it's 5:30 AM, do you sleep with your bike?

[randy]

Check that. Brain fart.

The red will have 12v all the time. The browns are switched throught the key. So,if you have 12v on the browns all the time, check your connector at the regulator and the connector for the key switch inside the light bucket. Those are the only places that the red and brown are likely to short together. Also, it's remotely possible that your regulator has an internal short. Try unplgging it and then testing.

[yamahansolo]

i work night shift so i got home at 430...


also i unplugged the regulator and everything else i could find??? still they short. and i did have the ground hooked to the battery and the posi was hooked to the volt meter. then i just touched the other voltmeter probe on various connections before and after removing and unpluging fuses...

[randy]

Sorry, Chris, but I don't understand exactly what you did.

Did you remove the positive battery cable from the battery?

Then did you connect the meter between the cable and the battery and the meter shows voltage?

[yamahansolo]

yep... the ground at the battery is hooked up. i unhooked the positive terminal. ummm i then put one wire from the meter to the positive battery terminal and the other wire i put on each side of the fuses 1 at a time...??? also now that i switched the two wires the relay no longer clicks. and i took the dimmer switch apart and the blinker wires are all fubared in there. they all broke off of the spots they were once connected too... i wonder if one of them was hitting something and shorting?

[randy]

OK,

First, go back and re-read what I wrote.

Then:

Remove the positive battery cable from the battery.

Replace all of the fuses.

Hook the meter between the battery and the free cable. This sets up the meter to show the voltage drain.

With the meter connected thus, one by one, remove a fuse. When you get to the fuse that drops the meter readingto zero, THAT is the circuit that was draining and you need to trace and find the short in that circuit.