No brake lights and on the road. KrZy8

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dcarver

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Hey guys looking for little help. I'm on the last day of a road trip and noticed that my cruise control was not kicking off when applying front or rear brake.

I have no brake lights Using either the front or rear brake. I don't know where the fuse is. Additionally I'm getting a very faint ABS blinking light on the instrument cluster.

Gen 2.

Fortunately I'll be taking back roads all the way back home so there will be a lot more Goa than whoa.

If you happen to know where the fuse is please post up. Or if you're aware that it might be a particular connector that would cause a Faint ABS light and no rear brake light.

Thanks in advance- Don

 
Do your horns work? Does the glove box open? If no to both questions you do have a blown Signaling System Fuse (15A), in the fuse box by the battery Neg terminal. If either of those work your problem is not a fuse. If there were an open in the brake light circuit the brake light would be on 100% of the time. If the brake lights are blown they wouldn't turn on
wink.png
But, they can turn on and nobody would know if the lights hadn't been locked in the sockets and they rattled out....

Coupler 17, two rows, long narrow connector (not square), 8 wires. The Green/Yellow wire that goes from the front brake lever through coupler 17 also goes to the ABS ECU. The G/Y wire should be +12 volts until the front brake switch opens as the lever is pulled in.

So, if it's the fuse, ya gotta ask yourself, why would a fuse spontaneously blow?

Does this have anything to do with passing through Sheephole Valley?

 
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Glove box and horn works. I did not know that open would cause the brake lights to stay on thank you for that. It's hard to tell in the daylight if the brake lights are on or not.

The first time I checked this morning I step on the rubric and they cannot flickered a little bit so I think I have an open somewhere.

I'm just going to head to the barn.

Thank you everyone

 
Sounds like a ground fault. I had a friend who' s Gold Wing trike had a problem with all the lights in the rear of the bike going out when either of the brakes were applied.

Turn out to be a problem at one of the connectors. Check everything from negative battery connection back.

Hope this helps.

 
Oh, and by the way the brake is not sticking👍

What I don't understand is how if a circuit opens the light would go on 100% of the time? I mean, I know better than to not believe in the professor at least it's giving me something to think about. 😜

 
Oh, and by the way the brake is not sticking
What I don't understand is how if a circuit opens the light would go on 100% of the time? I mean, I know better than to not believe in the professor at least it's giving me something to think about.
Relay's switched side have a normally open and a normally closed contacts. With no power the 'switch' part of the relay rests on the normally closed contact, which on the FJR's relay switch is connected to 12 volts and powers the brake light. Power is always supplied to the coil of the relay through the normally closed switch on the handlebar brake lever. Ground is always applied to the coil of the relay through the normally closed brake pedal switch. This keeps the coil of the relay always energized until the front brake lever opens power to the relay coil or the brake pedal opens the ground to the relay. When the relay is energized the switch part of the relay connects to the normally open contact which is an open pin on the FJR relay, so no power is sent to the brake lights. When either brake is activated it turns off the relay coil causing the switch part of the relay to connect with the normally closed pin which is connected to +12 volts, sending power to the brake lights. (At least that's the way the schematic is drawn.) Clear?
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Basically, the brake lights don't have to be turned on when the brakes are applied, they have to be turned off when the brakes are not applied.

There's a brown wire at the brake light relay. make sure there is 12 volts on that wire when the key is on.

Also at the relay, the Green/Yellow wire should be 12 volts with key on and front brake lever not pulled. Brown/Black wire should be ground with rear brake not pressed.

Relay should click and Yellow/Green wire go to 12 volts with key on and either brake being operated. If that doesn't happen but everything else is right, then it looks like it's the relay.

Thing is, any of these failures should leave the brake lights ON, not render them non-functional. So..... are the bulbs good? If you've been riding around with constant brake lights, maybe the brake filament is blown in both bulbs by now.

(BTW, difference between Green/Yellow and Yellow/Green if it's not apparent: Green/Yellow is green with yellow stripe, Yellow/Green is yellow with green stripe. Just in case that was fuzzy.)

 
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There's relay right beside the ABS controller block (you'll need to remove the RHS side panel to access it), you could check that this relay is working correctly, i.e. not stuck due to contact burn.

 
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A diagram might help. For non-YCC_S the diode and tap off to the YCC-S stuff isn't there.

In the "relaxed" state, both front and rear brake switches are made, the relay is energised, the brake lights held off. Either brake lever applied opens its switch, de-energises the relay coil, so the relay relaxes and makes the contact to power the brake lights.

All the contacts in the diagram below are shown with the ignition off and the brakes not applied.

1_brake.jpg


 
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Do your rear sidelights & rear indicators work?

There is a single ground from the Taillight assembly to the S1 spider (located near the air filter on the left hand side).

 
Ahh, the old relay in the circuit trick. I had actually (mostly) thought it through by the time I hit the Temblor mountain range. Ionbeams words and MCA's pix are wonderful - Thank You to all.

When the red light on the dash came on, my first thought was engine oil level warning. I had picked up a tank of not-so-good gas from a UnoCal station and was dealing with a rough engine so my little oh-shit sensors were on red alert. The oil checked fine, and once I diluted the 'bad' gas with 4 gallons of 'good' gas from he aux tank the miss went away.

Back to the lights-

When I depress the rear brake pedal I can hear a relay click in the right front cowling. When pulling the front brake lever, all I hear is the mechanical click of the switch. My hearing isn't all the great - I can't tell if the mechanical click is covering the relay click.

Over the years I've had several, possibly even 4, yamaha relays simply fail. Fans, headlights, are two that come immediately to mind. The fan relay quit just several weeks ago. Perhaps I'm reaching MTBF?

My plan is to ohm out the front brake switch. If operational, pull the right cowling and replace the relay.

All this still hasn't addressed the intermittent ABS light. It came on and off by itself twice over the 400 miles yesterday. Tested the ABS in the dirt and it's still functional.

 
In an earlier post, someone had mentioned that the brake signal also goes to the ABS ECU. You may want to sort out the brake lights first and see if the ABS light gets fixed at the same time.

So, are there no brake lights or are they on all the time? Since it appears the fuse is good if there were any other failures in the brake switching circuit the brake lights should be on all the time. If the relay failed, the wire between the relay and the tail lights (coupler 17 that the wire passes through) is open or the tail lights are burned out you won't have tail lights. Is it possible one tail light had been out and the other just quit? Um, are you missing both the tail lights AND the brake lights? Mebby I missed that someplace.

 
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Hi,
Maybe I have two investigation way !
First, in France YAMAHA MOTOR FRANCE (YMC) suggest a cleaning/greasing (and I suppose it's the same for all FJR) of the the axis of the brake pedal every 20000 km or 2 years, but this operation is never done, so the brake pedal never go back to the good position, and with the time, they are two many dust around the captor, and even if the rear brake is working, and abs too (only hydraulic action) the ECU and ABS ECU doesn't have the information.
To avoid this probleme, a simple cleaning of the rear brake captor, behind the brake pedal, and a greasing of the axis.
The second investigation way is directly on the ABS ECU., if you have the ECU ABS tester (ref : 90890-03149) you can display all errors stored in ECU.
Note : to avoid definitely the first issue, on my FJR, I have had a greaser ball (I'm not sur of the traduction) so know, I juste take one minutes to lubricate this axis. And it's never dry!

20150913.jpg


 
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In an earlier post, someone had mentioned that the brake signal also goes to the ABS ECU. You may want to sort out the brake lights first and see if the ABS light gets fixed at the same time.
So, are there no brake lights or are they on all the time? Since it appears the fuse is good if there were any other failures in the brake switching circuit the brake lights should be on all the time. If the relay failed, the wire between the relay and the tail lights (coupler 17 that the wire passes through) is open or the tail lights are burned out you won't have tail lights. Is it possible one tail light had been out and the other just quit? Um, are you missing both the tail lights AND the brake lights? Mebby I missed that someplace.
I'm about to go outside and put her on the lift.. The tail lights are on, turn signal lights work. Hard to tell if the brake filament is on or not. Hard to compare when in a single state mode. Looking at dusk last night, they don't appear to be on. And it's a pain in the are to pull the bulb since I had a CarverStiffieJob done to the subframe. I'll pull the manual and see where coupler 17 is. Is it on the front brake switch?

Hi,Maybe I have two investigation way !

First, in France YAMAHA MOTOR FRANCE (YMC) suggest a cleaning/greasing (and I suppose it's the same for all FJR) of the the axis of the brake pedal every 20000 km or 2 years, but this operation is never done, so the brake pedal never go back to the good position, and with the time, they are two many dust around the captor, and even if the rear brake is working, and abs too (only hydraulic action) the ECU and ABS ECU doesn't have the information.

To avoid this probleme, a simple cleaning of the rear brake captor, behind the brake pedal, and a greasing of the axis.

The second investigation way is directly on the ABS ECU., if you have the ECU ABS tester (ref : 90890-03149) you can display all errors stored in ECU.

Note : to avoid definitely the first issue, on my FJR, I have had a greaser ball (I'm not sur of the traduction) so know, I juste take one minutes to lubricate this axis. And it's never dry!

20150913.jpg
That's a great idea, and YES, I have one too! The rear brake lever has nice, even, free movement. Pretty sure that's not it.

 
.........., I have had a greaser ball (I'm not sur of the traduction) so know, I juste take one minutes to lubricate this axis. And it's never dry!
20150913.jpg
Greaser Ball is very descriptive, better than zerk... which would be your translation.

I'm stealing this idea too, can't say how many times I've taken that thing apart to clean/lube but the next time shall be the last.

 
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