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PIAA light repair

theblueeagle

'91 K100LT, '99 R1100RT
Does anyone have ideas on troubleshooting PIAA driving lights? I don't know the model of my lights but they have a metal housing and glass lenses. The control is a little oval push button and signal light. I've checked the fuse and ground and both are good. I tried to trace the wiring but it was very professionally installed. It's taped, tied and hidden in the harness under the tank (just like a factory mess). Before I go cutting the ties it would be nice to know what I should be looking for. Any suggestions or advice would be greatly appreciated.
 
You can look at their website and figure out the model...are they small 2" round/square, 4" 0r 6"

http://www.piaa.com/Powersports/lamps.html

Check the relay that should be close to the battery connections. A few sets of mine have had bad relays over the years. On most PIAA models it is a small black rectangular box about 1" X 2" and has a PIAA decal

The switch can be checked with a continuity tester after you unplug it from its white connector...typically about a 4' lead away from switch.

And PIAA really confuses the color code ...white is HOT, Black is the ground at the battery rings ...that's how some relays go bad really quick!:nono
 
There 'should' be a 'relay' which carries the load to the lights... the 'oval' button probably has a red/green LED to indicate light status.

Do either of these glow? If they "do", then chances are you have a blown fuse on the "power/load" side of the relay.

On the ones I've seen the relay is a "black" rectangle about 1/2 inch square and 1.5 inches long.
 
My switch doesn't glow at all. The fuse is good but it doesn't work. Is the relay a latching type? I wondered if the idea was for the switch to be a momentary on/off type. I can't find a schematic for the system and don't have the owner's manual.
 
Really hard to type up the debug process. I suggest you call PIAA... ask for a schematic.. I could not find one on their site.

PIAA CORPORATION, USA
3004 NE 181st Avenue, Portland, Oregon 97230
Telephone: 1-800-525-7422, 503-489-6666
Fax: 503-489-6600

If fuses are good and you have good ground wire from the relay/harness, it's pointing to the relay as the problem.

On the LT, most folks mount the 1100 PIAA's... so, need to figure that out first.

Next, contact the PIAA folks.. and ask them to email you the schematic that comes with the kit...

Then the cumulative help of the folks here can help.
 
My switch doesn't glow at all. The fuse is good but it doesn't work. Is the relay a latching type? I wondered if the idea was for the switch to be a momentary on/off type. I can't find a schematic for the system and don't have the owner's manual.

One other thought...maybe you already checked...some folks use the high beam circuit to initiate the relay...have to have the bike running and hit the hi beam...then the switch glows and you can turn on/off to have it on w/ hi beams or off all the way. I beleive red LED on...green LED off...I have installed two sets in the last two weeks for folks..another in the shop today two large 520's and one set of 1100X's...

still betting on a bad relay if you already tried the hi beam
 
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My switch doesn't glow at all. The fuse is good but it doesn't work. Is the relay a latching type? I wondered if the idea was for the switch to be a momentary on/off type. I can't find a schematic for the system and don't have the owner's manual.

any news? which lights were they?
 
Why the high beam only?

It took me a couple of months to try fixing this again. Fortunately it was just tied to the high beam circuit. The switch was mounted out of the way and couldn't be seen when riding. When I finally traced it all down it turns out the lights only work with the high beams. Any ideas as to why you would limit your PIAAs to only operate with high beam? I would like to have the option to use them whenever I want, not just on high.
 
Some states only allow aux. lights to be used in conjunction with the vehicles high beams. That could have been the case when your lights were wired.
 
Just find the trigger wire for the relay and move it to a source that goes on and off with the ignition. AND BE SURE DOUBLE CHECK THE AIM SO THE BEAMS AREN'T ANNYOING HIGH IF YOU OPERATE THEM WITH LOW BEAM.
 
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