no head or gauge lights

[floridajoe]

hi all need a little more help please .. 79 xs11s drove to work today sitting at idle and just stopped did it 3 times . after work no gauge or headlight and stopped 2 more times fuse is good and clue

[TopCatGr58]

Hey there Joe,

Okay, sounds like your charging system isn't working, headlight comes on only after engine starts AND charging system sends current/signal to headlight relay to switch on! You have enough power to start the bike "Surprisingly", but it's probably dropping below the 10.5 volts needed by the TCI to function, hence, quitting on you! You need to check the charging system, the battery, voltage regulator and such. Clean up all connectors around the charging circuit, folks have found problems and gotten them fixed just by a good cleaning of the contacts!

[thumperjsa]

I would bet on the connectors under the tank. I have had this happen to me a couple of times with the headlight. Although, I have not had the guages go out on me at the same time.

It could be the charging system, but start with the simple thing. Take of the seat and loosen the fuel tank enough to get your hands to the wire connectors and try wiggling them a bit.

[floridajoe]

wires are good and cleanedand battery is at 12.5 volts could it still be the charging system. last week i had the ballast resistor go out fixed that . how do i test charging system

[TopCatGr58]

Hey Joe,

Simplest test is with Voltage meter, on battery (+), check volts with engine running idle, should be about 12.5, then rev engine to 3K, should go up to 14 volts, if stays at 12.5, then either voltage regulator isn't working, or Stator isn't? They say put a piece of iron against side of stator, you should feel magnetic pull, if not, then stator isn't being electified, field coil isn't being activated!?

I'm no electrical guru, do a search on charging system, there have been several threads with very intricate details about how to check components!!

If charging system is seeming to work, then are you SURE the fuses are good?? Did you take them out, and check them for continuity? The glass ones can look good but still be bad, and the fuse holders can fall apart.....loose their tension!

Did you check all of the connectors inside the headlight bucket? Could be the RLU, you can bypass it to test it, there's a tech tip about removing it, but Ken Talbot also posted a quick easy bypass as well! Good Luck.

[skids]

I have been through this episode before. For mr it was a bad battery. The dog-gone thing would appear to be charged or even "self-charge" to a voltage that seemed OK, but would crap-out while riding (usually while at slow speed or waiting for a light). My charging system was fine. Load-testing the battery showed it to be bad,

[floridajoe]

i went thru and tested every thing you said and in the am will take battery to work and load test it . i put in a good rec/reg from a runing bike its good to work next to bike salvage yard. i will see with battery and go from there

[floridajoe]

load tested battery and it is good were next

[floridajoe]

checked fuses all good bypassed relay still have nothin

[Dennyz]

I had two '79s do something like this. It was very intermittent. The bike would die at a stop sign. All electrical components would be dead. I would walk home to get my truck only to have it start right up when I got back.

It turned out to be a bad/corroded crimp on the main electrical wire connector. This is the wire under the right side cover with woven red insulation. It connects to the solenoid where the positive battery cable attaches.

[floridajoe]

i have all power bike runs great .. but no headlight or gauge light

[TopCatGr58]

Hey Joe,

Okay, you said you bypassed the Relay, I think you meant the RLU, Reserve lighting unit!? There is also a headlight relay, called the Dimmer Relay in the manual's Schematic! It should have a Black, Red, Yellow, and Blue-black set of wires going to it!?

If you short the Red to the Yellow, and the headlights come on, then this relay possibly is bad! The Blue-Black wire sends the signal to activate/throw the relay. It comes from the RLU!

Did you test your second from left fuse holder with a voltmeter to ensure that there's power at both ends of the fuse holder terminals when the fuse is in?

Also, wonder if any of the wires in the handlebar switches could have come loose, they've been known to break a solder joint there as well!?
T.C.

[floridajoe]

yes bypassed RLU have power in and out fuse i will check handlebar switch. and check relay thanks t.c

[floridajoe]

T.C
bypassed the headlight relay i have lights head & gauge can that relay be bypassed or not

[TopCatGr58]

Hey Joe,

I'm glad you got them to work, but I apologize for the info I provided last night about which wires to short, I thought the Yellow wire that comes from the Alternator linked with the headlight circuit directly, but it was a long day, and I read the wiring diagram incorrectly!? I believe the yellow wire is the Relay "triggering" wire that connects the Red with the Blue/Blk, since the yellow wire shouldn't be energized till the bike is running and power is coming from the alternator, so it saves your battery from prematurely draining during the startup process!

So...the connection should have been the Red to the Blue/Blk. Which wires did you end up connecting to get the lights to come on? The Red is the hot from the fuse block! The yellow would be hot after the bike is running. The blue/blk goes to the RLU that then sends it to the headlight circuit.

So...if you permanently bypass the relay, then the headlights will probably come on as soon as you turn on the key, which could make it harder to start! I would think any 4 pole 12volt relay would work!? Or, you could wire in a switched relay, but that would involve lots of extra wires, a switch mounted somewhere, etc.!
T.C., definitely not an electrical GURU, just trying to help!?