Installation instructions must be followed exactly. It's recommended that the left bulb connections be made last after the unit has been tested and found to function correctly. This allows stepping through the installation methodically so any errors can be identified as to during which step they might have occurred.

Installation instructions must be followed exactly and all steps completed prior to applying power or the unit will be damaged. Connecting the unit backwards will damage the unit.

Problem

We are using this particular example to reveal what takes place more times than not. We are providing this exchange so you can see the results of an incorrect installation. The customer bought a closeout model headlight modulator and returned it because he said it didn't work. We didn't find anything wrong and agreed to give him credit toward one of the newer models. He insisted that he knew what he was doing and did everything correctly. Customer: I installed the replacement modulator tonight and it doesn't work either. It actually blows the motorcycle fuse when switched On. Prior to installing the unit I took great pains to insure it was connected properly and used a multimeter to confirm each wire of my circuit plug. I also tried it on my bench power supply and it makes the supply go into overload protection. I'm an electrical engineer so I understand electronics. Can I send this thing back for a refund? As much as I want it to work, I'm tired of messing with it. Us: Sorry but that won't be possible. I can tell you without any doubt that you've connected the unit backwards. If it's blowing the fuse or putting a power supply in overload then you've blown the suppression diode in the circuit which prevents total destruction. Note: We sent him a photo of the component in question and suggested he open the case and check the diode with an ohmmeter. Customer: Thanks for the picture and explanation. I took the box apart and checked the diode. Not only was it shorted, but the top was blown off. I replaced the diode and hooked it up to my bench power supply. It worked fine. Before I hook it to the bike I'm going to go through the wiring again and double check things.

Be sure to check your battery, especially after all the testing on an installation.

Question: I'm unsure about identifying the wires under the left storage pocket. Answer: The first thing to do is identify which part of the instructions apply to the different year models. The blue wire (A) that lights with the high beam switch "On" is the circuit from the switch to the bulb. This is the wire that's to be cut so the left high beam bulb no longer is fed power from the switch. The left bulb can be tested after cutting to assure the bulb does not light. The blue/black wire (B) is the normal high beam circuit that comes from the relay under the seat and powers the right bulb. It will also light when high beam is selected. The wire (A) that runs directly to the bulb, not the switch, is connected to wire (B) so the relay is now providing power to the left bulb as well as the right.

Question: After making the connection under the storage pocket and turn On the key and select the high beams they come On but after turning off the key the lights and ignition stay On and won't go off. Answer: The connection was made incorrectly. Instead of the side of the wire leading to the left headlight being connected to the right circuit the wire coming from the high beam switch was connected to the right circuit. Thus, when the lights are turned on high beam the power from the high beam switch feeds back through the right circuit to the relay rather than the left light which in turn powers the high beam relay. It creates what's called a latching relay, meaning that once it's turned on it won't shut off. The instructions need to be reviewed very carefully and the connections made correctly. If this problem is happening then we can guaranteed you've connected the wire incorrectly. The wire we instruct to cut goes to the light from the high beam switch. If you identify any other circuits then you haven't identified the correct wire. It imperative that you use a TEST LIGHT to confirm the wires and their functions.

Question: I have my headlight modulator installed in my 2008 goldwing.  Following the instructions, the unit flashed the right high beam headlight.  After modifying the wire under the left pouch the left high beam headlight won't flash.  The right one still operates correctly though.  The headlights do function normally otherwise.  The modulator turns on and off as it should, but only flashing the right high beam headlight.  any ideas?  i did check the wire connections at the left pouch with my test light. Answer: From the customer - I had cut the small blue one.  I redid it and used the larger one.  Works great!!!!  I did reconnect the other wire like it was supposed to be too.  You have an awesome modulator!!!  I love it!

Question: After installation the unit would not modulate. The bike was still in the garage under florescent lighting. Answer: The IR detector is not triggered by florescent light. It requires either sufficient sunlight or an incandescent bulb.

Question: After installation the unit would not modulate. A flashlight was used to trigger the IR detector. Answer: The light was not shined on the detector long enough. There is a one second delay in the new 2004 programming.

Question: I installed a competitors modulator on the GL1800 connected to the bulbs behind the fairing and it caused noise in my headset. I installed a Kriss modulator and it had a little but not nearly as bad. I installed a Kriss unit on my wife's bike under the seat and any noise wasn't noticeable. After changing my bike to under the seat the noise went away. Answer: The Honda GL1800 audio system very sensitive to any noise. Installation at the bulbs can introduce noise because of the close proximity of the audio system. Installation under the seat seems to eliminate the problem.

Question: After installation the unit modulated for less than 30 seconds and then the unit smoked. Answer: After discussion it was found that the installer had failed to connect the ground wire.

Question: After installation the unit seemed to modulate a couple of times and stopped. Smoke came out of the unit and lights would no longer come on. Answer: Upon inspection it was discovered a catastrophic failure due to the positive output wires also being tied to ground during installation. The circuit board along with the output wires were melted. No damage resulted to the motorcycle due to the fact that today's Mosfets (switching device in the modulator) operate at speeds that result in their failure before a fuse can blow.

Question: After installation the unit would not modulate the headlight properly. The bulbs had a very slight flash but not real noticeable. Answer: Discussion revealed that the input and output wires had been connected backwards. In some cases where the unit was immediately turned off no damage was caused but in most cases this destroys the unit. The input wires are those in the main bundle going into the unit. The output wires are by themselves on the opposite side of the box.

Question: After installation the unit would modulate only the right high beam headlight. Answer: The installer neglected to read all of the instruction pages and didn't make the connection for the left bulb. See note above (with the little fellow pointing at the box) regarding when to make this connection.

Question: Customer wired incorrectly and damaged the unit and returned it for circuit board replacement. The repair was made and tested OK. After the second installation the unit would not modulate correctly or stop modulating. The flash rate was very slow, about 1.5 seconds on and 1.5 seconds off. The unit was returned for inspection and found to function properly. Answer: It was discovered the customer incorrectly attached the programming wire permanently to a +12 volt source. The unit was in constant programming mode and would not begin proper operation.

Question: The headlight was intermittent or wouldn't light at all some of the time. This affected both the high beam and low beam. When high beam was selected the modulator seemed to modulate at an irregular rate or not modulate and the light was completely off. Answer: After some troubleshooting it was discovered that the starter switch was defective. On the Gold Wing motorcycle the starter switch has a circuit to activate the starter and one to activate the headlights. When the button is depressed the headlight turns off. If the headlight side of the switch is bad then the lights will be off all of the time.

Question: I have a Kennedy cell phone interface and after installing the connection my headlight modulator makes noise in my headset. Answer: Kennedy states their system is not compatible with a headlight modulator. They apparently did not realize modulators are used on the Gold Wing and failed to incorporate filtering into their design so it's overly sensitive to voltage changes in the electrical system.

Question: How do I bench test the modulator Unit? Answer: Connect the Blue output wire to a 12 volt test bulb (even a test light is OK). Attach the Green ground wire to battery negative first and then the Blue input (spaded) lead to the positive post. The input wires are always in the larger bundle of wires. The test light should illuminate. Shine a flashlight on the light detector to confirm the light modulates. Remember that there is usually a one second delay before modulating and a four second delay after removing the light from the detector lens.

Always use a test light when checking circuits.