No headlights

[swbarnett]

Got home today to find both of my headlights were out. Both high and low beam. All other electrical gizmos on the bike work just fine.

Fuses are fine (tried the spare and one of them in another hole). Bulbs are fine. I managed to get life into the lights by running a cable from the + side of the battery to light side fuse terminal. Obviously the problem is somewhere between the battery and the fuse box. I don't think I'm not getting any power to the light switch (although the indicators still work).

Could there be a problem with the ignition barrel? Is there anything else in there that could be at fault?

[caspernz]

Switch block is where I'd look next, at least by description of fault and diagnosis so far.

[mossy1200]

Lube any cables lately. I filled a switch block up once with aerosol cable lube and cable clamp tool by doing it at carb end.

[swbarnett]

Lube any cables lately. I filled a switch block up once with aerosol cable lube and cable clamp tool by doing it at carb end.
Haven't touched the cables for a while.

[oldiebutagoody]

Suzuki gsx600/750f fuse boxes are prone to failing. Some solutions I have read about are a complete replacement of the entire fuse box, or alternately continuing on with your wire from the positive terminal and doing a whole bypass, and install seperate headlight relays for high and low beam only using the light switch to operate the relays.

The above was/is a quite common fix for lighting issues on earlier GT/GS Suzukis. Bonus is you get REALLY good lighting to see by at night. I been meaning to do it myself on my own 600f. Ive only done the coil relay/rewire so far.

Another thing to check would be the headlight connector plug itself. Can go hard, crack and short out due to the heat caused by the inadequate gauge wiring used and current draw. Over the whole Suzuki loom, there can be as much as a 2 volt drop, meaning amperage has to increase to produce same wattage at the bulb, and we know increased Amperage (current) creates heat in thin gauge wiring or old hardened plugs/connectors..

Good luck, I have a PDF of what needs doing if you want it.

[swbarnett]

Suzuki gsx600/750f fuse boxes are prone to failing. Some solutions I have read about are a complete replacement of the entire fuse box, or alternately continuing on with your wire from the positive terminal and doing a whole bypass, and install seperate headlight relays for high and low beam only using the light switch to operate the relays.

The above was/is a quite common fix for lighting issues on earlier GT/GS Suzukis. Bonus is you get REALLY good lighting to see by at night. I been meaning to do it myself on my own 600f. Ive only done the coil relay/rewire so far.

Another thing to check would be the headlight connector plug itself. Can go hard, crack and short out due to the heat caused by the inadequate gauge wiring used and current draw. Over the whole Suzuki loom, there can be as much as a 2 volt drop, meaning amperage has to increase to produce same wattage at the bulb, and we know increased Amperage (current) creates heat in thin gauge wiring or old hardened plugs/connectors..

Good luck, I have a PDF of what needs doing if you want it.
Sounds like a very real possibility. I was looking at the wiring diagram and can't see how it could be the ignition switch as the same wire powers other lights that still work.

That PDF would be much appreciated. PM sent.

[oldiebutagoody]

sent.

it only covers rewiring lights away from the fuse box though. Basically wiring up a new sub loom with relay and own fuse.

cheers.

[Akzle]

git cher ass a multimieter and some learn.

[jellywrestler]

install seperate headlight relays for high and low beam only using the light switch to operate the relays.


is it a lights on all the time model, whether it is or not you could install one double pole relay with the feed to it, a signal from the light switch to the common, either high or low to operate the relay, not both and use the two poles to go to high and low, half the cost half the hassle

[swbarnett]

sent.

it only covers rewiring lights away from the fuse box though. Basically wiring up a new sub loom with relay and own fuse.

cheers.
Thanks.

Had a quick read this morning. Looks pretty much like what I've already done for my horn and USB charger.

The one thing that has me a little perplexed is that I don't seem to be getting power to the 'bar switch. If I'm not getting power to the headlight switch I won't be able to use it to control any relays.

The same switch block runs the indicators and they're working so there's obviously some power getting there. I may need to do some more rigorous testing tonight. I'll pull the switch out of the switch block so I can be sure of getting good contact.

[swbarnett]

git cher ass a multimieter and some learn.
Have the meter. Have a little bit of "learn", getting more slowly (wiring diagrams are confusing).

[swbarnett]

One more question - is the fuse box between the + of the battery and the 'bar switch? As I said - the wiring diagram is confusing.

[jellywrestler]

[QUOTE=swbarnett;1131006497


The same switch block runs the indicators and they're working so there's obviously some power getting there. [/QUOTE]

you can't live without your headlights at times so they're usually on a fused circuit on their own so when a sil;ly little indicator or horn fails it doesn't take the lights out, you need a wiring diagram and someone who can read it.

[swbarnett]

you can't live without your headlights at times so they're usually on a fused circuit on their own so when a sil;ly little indicator or horn fails it doesn't take the lights out,
That makes sense.


you need a wiring diagram and someone who can read it.
Indeed. I have the wiring diagram and as long as my eyes can follow the lines it makes some sense. I'll have a closer look at it tonight when I pull the switch block apart again.

[neels]

It is probably a different power feed for the indicators than for the headlights, as the indicator flasher unit is normally between the power supply and the handlebar switch.

I'd be starting with finding the connector for the switch block and check for fried contacts, if not that would have to resort to following the volts from one end to the other to see where they stop, a test lamp will give more definite results than a multimeter if there is a dodgy connection somewhere.

[Hugo Nougo]

I had a similar problem on a honda blackbird, after much head scratching it turned out to be the start button sticking on as the start system disconnects power to headlights while depressed, I had the fairings off and everything when i accidentally knocked the switch and lights came on, hope this helps, good luck.

[swbarnett]

It is probably a different power feed for the indicators than for the headlights, as the indicator flasher unit is normally between the power supply and the handlebar switch.

I'd be starting with finding the connector for the switch block and check for fried contacts, if not that would have to resort to following the volts from one end to the other to see where they stop, a test lamp will give more definite results than a multimeter if there is a dodgy connection somewhere.
I've done some testing with a mutlimeter. I don't get any volatge at the light plug. I'll check the 'bar switch more thoroughly tonight.

[swbarnett]

I had a similar problem on a honda blackbird, after much head scratching it turned out to be the start button sticking on as the start system disconnects power to headlights while depressed, I had the fairings off and everything when i accidentally knocked the switch and lights came on, hope this helps, good luck.
Interesting thought. Another thing to ckeck tonight.

[swbarnett]

Just pulled the light switch block apart. As soon as I pulled the switch out of the block the lights started working. Not sure what yet but something in there is flaky. Probably contact I'm thinking. I'll have a good look at the wire attachment points - might me a loose wire.

[nzspokes]

they were dim on Sunday.

[swbarnett]

Pulled the switch apart. The contacts were very dirty and one side was badly corroded. Managed to clean it all up with a bit of 0000 steel wool I had lying around.

[swbarnett]

they were dim on Sunday.
Doesn't surprise me. Haven't been out after dark for a few weeks. Only noticed it this time because I was late home from work.

They werer fine last week when I did my weekly check. Must've been right on the cusp.

[oldiebutagoody]

:woohoo:


10 characters

[swbarnett]

Went out on Thursday night. The headlights were fine. Went to start the bike on Friday morning and nothing.

Split the switch open again last night and found no current getting to it. Did some continuity testing and found both high and low beam fine from switch to fuse. Also, Harness plug to switch was fine. Obviously something loose or broken in the harness past the plug.

Had a think and decided to put a relay in to supply power to the switch. Then it dawned on me that I already have a relay in for a USB charger under the seat. This morning I ran a new wire from there to the switch power line and voila, I now have lights again. Don't know exactly were the break is. It'd be a nightmare to find and the relay works so I'm happy.

PS: Timing worked out brilliantly. Bike's due for a minor service next weekend so, while I have everything off (fairing, tank etc.) I did it today. Now I have labout weekend completely free with a bike that works.

[oldiebutagoody]

Thanks for relaying that update to us. :cool:

[swbarnett]

Thanks for relaying that update to us. :cool:
No worries. Least I can do for the help I've had. If nothing else it got me thinking along the right lines.

More than 24 hours now and they're still working...

[oldiebutagoody]

I'd still check the overall voltage drop at the light bulb connector plug. If its a couple volts lower than 12v it will be drawing higher Amperage/current through the handlebar switch, which will accelerate deterioration in those contacts. If the voltage drop is not attended to, the problem will return at some point.

Re-routing higher voltage to the switch, and then subsequently on to the bulb will provide the higher voltage and lower current supply required to operate as it did when new. It is however still the switch contacts routing all the current draw to the bulb that is the design problem on what is now a 10 year old bike. This is obviously working well for you, and may continue for a long time, but it sounds like the switch contacts are already a bit dicey.

Re-routing the main current draw via a relay to the bulb, and just activating the relay via the handlebar switch contacts is the final fix.

Mr Suzuki made a good cheap model in the GSX/F range. It is what it is though, and prone to ageing. Mine (600f) is 1992 and still going strong with thoughtful maintenance being required a bit more frequently now.

I recently bought a 1996 Bandit that seems it has never had maintenance done. Still a great bike for what it is. Working my way through that now.

[oldiebutagoody]

is it a lights on all the time model, whether it is or not you could install one double pole relay with the feed to it, a signal from the light switch to the common, either high or low to operate the relay, not both and use the two poles to go to high and low, half the cost half the hassle

Yeah Nah the PDF I sent him covered that, and various other scenarios, and the relay types required/pin config required.

IIRC none of the GSX/F models in NZ new were lights on all the time. The PDF covers setting up for lights on full time.

If Ducati have been turning motorcyclists into mechanics since year dot, Mr Suzuki has been turning us into electricians......

[swbarnett]

I'd still check the overall voltage drop at the light bulb connector plug. If its a couple volts lower than 12v it will be drawing higher Amperage/current through the handlebar switch, which will accelerate deterioration in those contacts. If the voltage drop is not attended to, the problem will return at some point.
In the short time it was working after cleaning the switch the voltage was 12.something.

[oldiebutagoody]

In the short time it was working after cleaning the switch the voltage was 12.something.

You should be all good then. Bit of di-electric grease might be helpful on the switch contacts too.

Glad you are sorted.