The curious case of headlights. 3 Electricians gave up so far, any Kat experts, help!

[Airborne]

Hello Everybody,

As always, I seek your guidance, that seems to be the most accurate and helpful with kat problems. I have a headlights issue, that is similar to the other thread, but then again, totally different, since I have exhausted all the advises that have been given to the other member of the forum.

I have a 1998 Katana 600. My headlights stopped working this Sunday. Initially I thought it was the bulbs, as they have been working just fine for years, so it would be probably their time anyway. Apparently only one bulb burnt off, while the other seemed fine. I still bought two as replacements. After installing new bulbs, nothing happened. I checked other lights (indicators and little light above headlights) and they were working just fine. Of course a quick check of fuses proved that the problem wasn't there. I took a voltmeter to check whether I got electricity from the plug itself, as I have heard that bulb plugs often burn out. Guess what, 11.46 volt reading out of both plugs!

Puzzled at this stage, I took the front harness off and checked the ground, checked resistance and everything seemed to be fine. Thinking I might be delusional, I had electrician at my work check the front harness for potential breakage and it worked absolutely fine, resistance like it should be. I then started checking the main harness and there was electricity coming of the plug too. Thinking maybe it's a ground issue, I checked the resistance on the main harness as well and it worked absolutely fine. It kinda seemed obvious since indicators and other lights work fine, while sharing ground on main harness, correct?

I took it then to autozone, along with a totally stripped bike. Their electrics guy plugged everything in and got similar reading as my electrician at work and me back at home. He was as puzzled so he checked the bulb again, which worked just fine. We then took the front harness and checked it against a car battery and all the lights were lit, including the headlight, proving that the harness and plugs were working absolutely fine.

The next step was to investigate the low/high beam switch. Pain in the ass to later putt it together once you take the cord out of it, but 35 mins later it was back in its original shape, with me even more puzzled once I verified that there was electricity in the switch as well.

I'm running out of ideas for what to check to further troubleshoot this. Please let me know if any of you had similar problems or would have any idea how to further troubleshoot it.

Thank you and I look forward to hearing back from you!

kind regards,
Airborne

[Kreylyn]

You have power to the lights, and that power then runs to the hi/low switch? You have verified this?

If yes... then it's a ground issue from the switch. It COULD be the switch contacts need cleaning.

The hi/low works by using the same ground, and you toggle between power contacts for the hi or low beam ground wires from the headlights.

So as a test... take the 2 screws out of the pod for the hi/low switch so you can see the wire contact points. Use aux wire to work as the ground, and connect it to the hi or low input wires. That should turn lights on. If you see that happen, then it's the switch needing cleaning, or the ground from that switch point to the fuse box.

Fuses on Kats are the last point to complete the circuit.

Krey

[Airborne]

Hello Krey,

Thank you for the prompt reply and always awesome assistance.

I have just completed the test, per your instructions (please find a picture below).

Yes, I have previously verified with a voltmeter that the high/low switch was getting power. I also checked previously the resistance by plugging into the switch and grounding, and it worked fine, however since I'm not an electrician I wasn't sure I did it correctly.

Following the testing, I connected the aux wire to one of the frame's unpainted bolts (and few other bare places, to make sure I'm doing it right) and the connection on the white wire within the switch (which I believe is ground). I have also tried this with all three wires, just to rule out any chance of me making a stupid mistake. The test did not show any results. The light did not even blink.

What would you suggest for the next step or another test, that might get me closer to finding the culprit?

Thank you and I look forward to hearing back from you!

Kind regards,
Airborne

P.S. I also attached a picture of a dashboard while bike was in high beam. The dashboard does not even show the high beam indicator, but I'm assuming it is just to let me know the light is out.

[Kreylyn]

Hello Krey,

Thank you for the prompt reply and always awesome assistance.

I have just completed the test, per your instructions (please find a picture below).

Yes, I have previously verified with a voltmeter that the high/low switch was getting power. I also checked previously the resistance by plugging into the switch and grounding, and it worked fine, however since I'm not an electrician I wasn't sure I did it correctly.

Following the testing, I connected the aux wire to one of the frame's unpainted bolts (and few other bare places, to make sure I'm doing it right) and the connection on the white wire within the switch (which I believe is ground). I have also tried this with all three wires, just to rule out any chance of me making a stupid mistake. The test did not show any results. The light did not even blink.

What would you suggest for the next step or another test, that might get me closer to finding the culprit?

Thank you and I look forward to hearing back from you!

Kind regards,
Airborne

P.S. I also attached a picture of a dashboard while bike was in high beam. The dashboard does not even show the high beam indicator, but I'm assuming it is just to let me know the light is out.

At the battery on the negative post... there will be 2 wires coming off that point. A large one, and a small one. Verify the small one has a good connection at the battery post, and trace it back to verify the connection point just a short distance away is clean, and properly connected. Wiggle that with the high beams on.


The high beam dash light should be on even if the headlights are not working. This suggests to me the secondary ground wire is not fully connected.


Krey

[Airborne]

Hello Krey,

Thank you for the prompt response.

Following your advice, I did get to the battery and checked the small cable on negative side. Connection seems to be firm and strong (please find a picture attached) and upon further inspection of the cable, isolation seems to be just fine and the wire goes into the main harness without any problems.

I did wiggle it multiple times near the connection and also alongside the wire going into the harness and nothing changed (I did keep it on high beam). There was no dashboard light, nor there was headlight reaction at all.

Please kindly let me know, where else should I look for problems on this...

Thank you so much for your help and I look forward to hearing back from you!

Kind regards,
Airborne

[steves]

So, to confirm you did check that the fuse is good, and there's no rubbing under the tank?

[Airborne]

Steve,

That is correct. Checking fuses was the first thing I did. Also, I am getting power reading on a voltmeter, from the plug, which would probably not work if the fuse was bad, I think.

The wire on a battery seems to be in a really good shape as well, so does the whole harness.

[steves]

And the socket itself that the bulb goes into is in good shape and not melted or anything?

[Airborne]

And the socket itself that the bulb goes into is in good shape and not melted or anything?

That's correct. Both are in perfect shape. I'll send some pictures as soon as I come back from business trip tomorrow. I don't know where to further look for problems or how to troubleshoot it anymore.

[ernie]

Opps

Ok, had a look at the wiring diagram. I know you checked your fuses first BUT from what I can read of the wiring diagram you have just blown them if you had power to the switch when you connected the switch to ground. The switch on a post should be HIGH, the ground is not switched.
So check your fuses again.

Next can you measure the resistance of the ground from the headlight bulb plug to the frame and let us know what resistance you get.

[Airborne]

Hello Ernie,

Thank you for joining the discussion on this and offering your assistance.

Per your advice, I have verified all fuses to be in working order (I have swapped the headlight with blinker and blinker works fine with every 15 fuse, while headlights don't).

For your and others interest, please find a picture of the bulb plugs, attached. They seem in a really good shape.

Finally, I did the resistance test per your instruction and both plugs have a similar reading (0.66). Please find a picture attached.

Thank you and I look forward to hearing back from you regarding further steps!

Kind regards,
Airborne

[ernie]

Ok, so grounds good and you have voltage so the only thing that might be stopping you is a loading issue.
Can you install 1 bulb into either of the plugs and then measure the voltage at the other.

The only other thing I can think to check is the resistance on the positive from the battery. You will need to disconnect the battery first though or that will screw with the DMM.

[Stinger02]

Are we sure the connector isn't the issue? On my kat, the lights would come on for about 10 minutes then go out. It was intermittent. I traced my problem back to the
Connector under the 3rd light and cut both ends of the wire and spliced them back together. Never had another problem. Maybe if your not willing to cut the wires, then try jumping the wire somehow

[ZukiFred]

Are we sure the connector isn't the issue? On my kat, the lights would come on for about 10 minutes then go out. It was intermittent. I traced my problem back to the
Connector under the 3rd light and cut both ends of the wire and spliced them back together. Never had another problem. Maybe if your not willing to cut the wires, then try jumping the wire somehow

I had an issue with the same connector on mine as well.
No headlights and no high beam indicator light.

[Airborne]

Curious case of a....connector resolved!

Hello Guys,

Thank you for all your advises and posts. I have now found the culprit and must admit that Stinger02 hit the nail on the head. It was the connector issues and unfortunately I found it by an accident, so none of my fancy troubleshooting worked, lol. Please find the picture attached.

I was working on a battery trying to create a bypass to narrow down the problem and see what the hell was going on there while suddenly everything just worked fine and I didn't know how. Nothing I did made a difference at that point so I just started going through the wires that I touched earlier that day and step by step I started moving things around and found a connector issue. As soon as I opened it I found oxidation, which was probably the issue. I cleaned it thoroughly and have no issues at all, even if I shake and tap the connector.

Your help was invaluable in narrowing it down, therefore thank you very much for helping on this. In case anyone has a similar problem, I would be happy to help with pictures or anything else, since I went through miles of wires to find that little bastard!

Kind regards,
Airborne