86 VFR - tail lights, but no brake lights

Hi guys,

I have an '86 VFR that suddenly the brake lights are no longer illuminating, neither from front or rear pedal.

I have confirmed that both filaments in both bulbs are capable of illuminating. Also all fuses are good. Wondering if there are common areas to look at, or if I need to figure out which wire energizes the brake filament and keep tracing it back.

 

Hi and Welcome to the MadHouse

When you get time please swing by the "introductions" part of the forum to say hi to the rest of the folks on here, and tell us a bit about your VFR and your riding history. The folks on here really like photos so feel free to include a photo of your VFR750. Its easy just click the "upload a file" link and follow the prompt to select and upload an image from your computer. You may also want to update your forum profile to include an approximate location that way if you really need help with a problem you may find someone living nearby may be willing to swing by and offer advice or pick up a spanner especially if you have a well stocked beer fridge.

As for the brake lights not illuminating I wonder if you have removed the seat recently?

As you say that the bulbs are OK but applying hand/foot brake levers does not result in the brake light illuminating I suspect we are looking at a common mode failure location. In essence somewhere where the same circuit is shared by the hand brake and foot brake. The most obvious candidate is the joint in the feed to the brake light cabling located under the seat. If corrosion has built up on that joint then the brake light won't illuminate - likewise if the joint is loose or completely detached.

It should be easy to locate and probably sensible to disconnect both terminals and then clean and secure the connectors. Hopefully that will sort the problem out.

Otherwise head for section 20-9 to 20-11 of the 750 manual and follow the fault finding advice. If you need a copy of the PDF manual send me a PM on the forum.

Good luck - Let us now how you get on.



SkiMad

 

Thanks for the warm welcome! Unfortunatley I don't have any good pics of the bike at the moment. I've had it about 2 years - I bought it off a guy who was going to part it out because it was running on 3 cylinders. I got it cheap from him and was able to revive it with new plugs and a good carb cleaning. It has 100,000kms on it, and pretty much looks like it has Looks 'good from far, but far from good'. It does have a nice stainless steel brake lines. I went through and rebuilt the master cylinders, clutch system, put new tires on it and have been happily riding around during the 6 months of decent weather we get here in Ottawa.

I have the seat off now to try troubleshooting this issue - however it had not been off in a while before that. Today I removed the pigtail with the bulbs in the tail - so I had access to the connector that feeds them. I put a multimeter on the wires and found the tail light wire (constant 12v with ignition on) and found the brake wire (green with yellow stripe I believe). When I have the multimeter on that wire and pull the brake lever, my reading goes from 0v to 0.4v. I'm not electrical genius but I think I have a frayed wire that is mostly shorting to ground, or a wire that is mostly broken. What do you think?

 

Best thing to do is to bridge the front brake light switch and do same with rear at its plug but not at the same time.

Whilst your there check for power in.

Black or brown will usually be the live feed and green/yellow or green/white feed to the light from the switch.

 

Thanks guys. Turned out to be an easy fix, the contacts on the front brake switch were just really dirty and no longer making a connection. I removed the switch, sanded the terminals and treated it to some contact cleaner. Rear brake also needed a bit of adjustment to engage sooner. So got all that done tonight and should be ready to roll around as soon as it warms up!!

 

Thanks for finding the time to provide an update on how this was resolved Chadz.

Remembering to provide follow up is so important to making this forum a valuable reference source.

Sadly too often people fail to post follow up on threads where they have asked for advice on a problem so it is never clear what advice was helpful and how the problem was resolved.

PS - Don't forget to visit the Introductions section and post up a photo or two of your VFR especially now you have the brakes working OK.

Take Care and have fun.




SkiMad

 

Once contacts are sanded, be ready to clean them in a while. Best to replace them.