Headlight problem, anyone good at reading the electrical schematic?

[Martin#30]

Morning all,

After a little over 3 years, and 49,000 miles, my beloved bike has left me stranded for the first time.

Both headlights (and both low and high beam) have all suddenly failed. RAC man came to my rescue, and managed to sort a heath robinson fix by connecting the battery +ve straight to one of the left hand headlight pins via an inline fuse. When this wire is connected, both low beams work but not the high beams. Lights of course now stay on permanently, so I remove the fuse to turn them off.

All the fuses are fine, as are both low and high beam relays (they click when applying 12V to the coil pins, and the switched pins show zero ohms across them when the coil pins have 12V).

Normally, I would suspect an un-loader relay has failed, the part that disables the headlights when we press the starter. However, looking at the wiring diagram, there is no such un-loader relay and it seems to be the main ECU that controls this.

I guess the link between the ECU and the low-beam relay has failed, but the wiring diag is very confusing to my simple mind.

Anyone got any thoughts? Can anyone read the electrical schematic and suggest which wire colours/pins to test between the ECU and the relay?

Thanks,

Martin.

[viper]

ive got no idea, if the bike was mine i would work it through trial and error and testing everything with a meter starting at the bulbs and working backwards  through the switch gear , relays and supply.
i wouldnt even attempt to start testing ecu through fear of damaging it.
An un-loader?  never heard of that, I thought the main lights only came on after the engine was started which suggests a relay fired by the altenator circuit?

[stig414]

The headlight relays (2 of) are fed from another relay in the relay box, which is in turn fed from another one. Have you lost any other circuits that are normally only working whilst the engine is running?
Daz

[Debs]

I had similar happen to me last year while in Austria.. The same 'fix it' was done so I could carry on..
Back at Bournemouth Kawasaki they found the problem to be the earth block connections which is located somewhere near the indicator relays to the left of the tank. It is a connection block and one of the connections needed cleaning up..

[Lonewolf]

Martin, hopefully it will be a relatively simple fix as Deb's has mentioned. My guess is Asif will be able to identify the faulty component from the electrical schematic , he's good at all that stuff.

Good luck with it.

[Richard]

Hi

No diagram to hand at the mo, but from memory the lights are fed from the 30A fuse that is hiding next to the battery.
If you take the battery out, to the left there is a red connector, press the lock clip in and pull it off, the fuse is hiding underneath, and there is a spare fuse on the side of the housing.

Richard

Having found the diagram I am wrong, lights don't go through the fuse by the battery.
Both fed from fuse box 1, fuse 5 and 6, and the realy control cct fed from same box fuse 2.

[Debs]

Hi

No diagram to hand at the mo, but from memory the lights are fed from the 30A fuse that is hiding next to the battery.
If you take the battery out, to the left there is a red connector, press the lock clip in and pull it off, the fuse is hiding underneath, and there is a spare fuse on the side of the housing.

That fuse you are talking about Richard is the fuse for the Solenoid. I know because it blew when I was fitting my new wiring loom.. Had to call Kawasaki because the bike was dead. It was that fuse that had blown.

[Martin#30]

Thanks all for the pointers.

From the limited testing I have managed to do so far, it looks like I am not getting a good +ve to the Red/Yellow wire feeding the pin that energises the relay coil. I am getting 0.4V instead of the 14-ish I would expect when the bike is running.

So, I assume that the low beam headlight relay is never energising, and thus the lights do not turn on.

Now I need to try and understand where that Red/Yellow wire/pin is supposed to be fed from. Trying to trace it back on the wiring diagram is giving me a headache 

Martin.

[Andy]

Thanks all for the pointers.

From the limited testing I have managed to do so far, it looks like I am not getting a good +ve to the Red/Yellow wire feeding the pin that energises the relay coil. I am getting 0.4V instead of the 14-ish I would expect when the bike is running.

So, I assume that the low beam headlight relay is never energising, and thus the lights do not turn on.

Now I need to try and understand where that Red/Yellow wire/pin is supposed to be fed from. Trying to trace it back on the wiring diagram is giving me a headache 

Martin.

Are you using headlight / tail light diagram? R / Y on low beam relay comes from dimmer switch. BK / Y earths could be a common :-) issue. Moving parts i.e. switches and relays are most unreliable items :-(

[Rusty]

+1 Andy. 

[Martin#30]

Are you using headlight / tail light diagram? R / Y on low beam relay comes from dimmer switch. BK / Y earths could be a common :-) issue. Moving parts i.e. switches and relays are most unreliable items :-(

Thanks Andy. I must admit that I initially thought I had the same issue that Debs mentioned above, and was thinking there was an earth problem. However, I can see a very low resistance (<0.01 ohms) between the GND pins feeding the relay and the frame.

I think my next step is as you say above, what the electrical schematic calls the 'Dimmer Switch'. I imagine this is the high/low beam switch. I shall see if I can dismantle and clean.

Martin.

[Lonewolf]

+1 Andy. 

  Nigel, be honest, you haven't got a clue what Andy was referring to have you?


Martin, would it be easier and less frustrating to just get an auto electrician at a Kwak dealer to sort it out for you, they may well have experienced this problem in the past and be able to put their finger on it immediately, maybe an hours labour?

[Debs]

Martin, would it be easier and less frustrating to just get an auto electrician at a Kwak dealer to sort it out for you, they may well have experienced this problem in the past and be able to put their finger on it immediately, maybe an hours labour?

[Andy]

  Nigel, be honest, you haven't got a clue what Andy was referring to have you?


Martin, would it be easier and less frustrating to just get an auto electrician at a Kwak dealer to sort it out for you, they may well have experienced this problem in the past and be able to put their finger on it immediately, maybe an hours labour?

Typical Yorkshireman generous with other peoples money :-) I confuse myself sometimes :-) a relay doesn't draw much current but lamps themselves do and would highlight a poor earth. Crock clipping on another earth to lights (don't earth +ve connection....) would be another test. I'd bet five pounds of Wolf's money on dip switch as they spend 90% of the time stuck in same position:-)

[Martin#30]

Martin, would it be easier and less frustrating to just get an auto electrician at a Kwak dealer to sort it out for you, they may well have experienced this problem in the past and be able to put their finger on it immediately, maybe an hours labour?

For sure, but I quite like learning about these sort of things - plus I get a fair bit of satisfaction from solving these sort of things myself.

My job does not involve creating things, so I think my inner caveman needs to actually build/fix stuff. At least I think that is why I am currently turbocharging my MX5 on a cold, and wet wintry driveway 

If I have not fixed it by the time it goes in for it's 48k service (a couple of weeks), then I will add it to the list. This may prove to be the world's most costly GTR service at this rate - the big 24k valve service, plus it needs front brakes and tyres, and a potentially tricky to diagnose electrical fault. Sorry kids, no new shoes for a year 

Martin.