wild foamy Posted November 23, 2008 Share Posted November 23, 2008 hi everyone. the Tail-lamp on my DT50 has stopped working, it will work as a brake light but with the headlights on it doesnt light up like it normally should. i've cleaned the connections and checked the bulb but everything seems fine, it had an MOT on Friday and my dad pointed it out on saturday... perhaps someone can shed some light on this problem? O.o - Steve Link to comment Share on other sites More sharing options...
JimR Posted November 23, 2008 Share Posted November 23, 2008 hi everyone. the Tail-lamp on my DT50 has stopped working, it will work as a brake light but with the headlights on it doesnt light up like it normally should. i've cleaned the connections and checked the bulb but everything seems fine, it had an MOT on Friday and my dad pointed it out on saturday... perhaps someone can shed some light on this problem? O.o - Steve Hi Steve, I guess the yellow wire is still connected to the rear light and also the head light works ? if they dont a yellow wire is suspect. you could check the earth to the rear light but as the brake light works I guess the earth is ok. you appeared to have checked every box unless you missed one !!! from your post it should work !!! i'll have to shed some light on your rear mudguard earths !!!! Regards Jim Link to comment Share on other sites More sharing options...
wild foamy Posted November 23, 2008 Author Share Posted November 23, 2008 the earth seems okay, no visible damage and i am getting voltage through both the blue and yellow wires. t'is confusing O.o Link to comment Share on other sites More sharing options...
Moderator Airhead Posted November 23, 2008 Moderator Share Posted November 23, 2008 You should have a spare bulb, so try that one. Link to comment Share on other sites More sharing options...
wild foamy Posted November 24, 2008 Author Share Posted November 24, 2008 Bulb is fine, and its the blue light which is the running light, the yellow wire is for the brakes and that works fine. with the headlight on it puts out about 0.3 volts, so obviously somewere in the loom there is either break or high resistance that is stopping the juice getting to the back light :S even on the plug straight out of the switchgear i am not getting anything above 0.3V volts, and the switchgear was brand new and working when i put it on there a week or so ago so its not that. any more ideas? this one has me stumped O.o, i havent changed any of the wiring so im not sure why it would suddenly not work. is there a regulator or something in the circuit that may be faulty? and whilst im here, anyone know where i can find a wiring diagram for the complete bike and/or brake lamp circuit Link to comment Share on other sites More sharing options...
JimR Posted November 24, 2008 Share Posted November 24, 2008 Bulb is fine, and its the blue light which is the running light, the yellow wire is for the brakes and that works fine. with the headlight on it puts out about 0.3 volts, so obviously somewere in the loom there is either break or high resistance that is stopping the juice getting to the back light :S even on the plug straight out of the switchgear i am not getting anything above 0.3V volts, and the switchgear was brand new and working when i put it on there a week or so ago so its not that. any more ideas? this one has me stumped O.o, i havent changed any of the wiring so im not sure why it would suddenly not work. is there a regulator or something in the circuit that may be faulty? and whilst im here, anyone know where i can find a wiring diagram for the complete bike and/or brake lamp circuit its a dry joint ! from memory there is a soldered joint very close to the ht coil (under the tank but u know that !) pre MX's had a resistor on a male/female connector living by the ht coil but again, from memory, the MX just had a soldered connection in the loom at about the same place ..... but try running a wire from the head light (which works) to the blue at the connector under the saddle if it works the problem does lie in the loom. Its odd tho I seem to remember the Yellow suppling 6vac from the mag and the main lights being supplied from there ... I'm off over the net to find a diagram let you know when I have a diagram and can advise you better ! Regards Jim Link to comment Share on other sites More sharing options...
wild foamy Posted November 24, 2008 Author Share Posted November 24, 2008 thanks mate, will pull the tank off tonight and have a look-see. the whole loom from the connection under the seat to the front is covered in insulation though, how will i know where the solder joint is? Link to comment Share on other sites More sharing options...
JimR Posted November 24, 2008 Share Posted November 24, 2008 thanks mate, will pull the tank off tonight and have a look-see. the whole loom from the connection under the seat to the front is covered in insulation though, how will i know where the solder joint is? not got a diagram yet but the soldered connection will be around the HT coil area of the loom .. where the plastic tube turns into tape !!! if the connection under the seat is 'taped' I'd check that out first .... Regards Jim Link to comment Share on other sites More sharing options...
Moderator Cynic Posted November 24, 2008 Moderator Share Posted November 24, 2008 The yellow from the main beam switch and the blue at the back of the bike are completely un connected, the headlight runs solely on ac if you run a jumper to the headlight you will be putting AC into the battery , use the battery and take a jumper from that to the blue tail light connection. If that is good get behind the headlight and do the same to the blue wire from the lighting switch. The line to the taillight comes straight from there, Link to comment Share on other sites More sharing options...
Moderator Airhead Posted November 24, 2008 Moderator Share Posted November 24, 2008 Steve, have you got a multi meter? Before you start stripping back the loom you should unplug your tail light connections and measure between the two filament connections and the black, i know you said it is a good bulb and it maybe so but the contact is spring loaded and can stick as mine has in the past, it makes sense to eliminate this back light as a potential problem If you havent got a meter you could do as Cynic said but leave the black connected and jumper battery+ to the filament bullet male connectors, be careful not to let jumper touch chassis anywhere or you could simply remove the bulb, give a good spray of WD40 in the socket and shove the contact up and down to ensure its free! Link to comment Share on other sites More sharing options...
wild foamy Posted November 24, 2008 Author Share Posted November 24, 2008 Yeh i have checked with a multimeter and im getting voltage thorugh the blue wire for my brake light but only about 0.3 for the running light the contact is fine, have checked that when removing/replacing the bulb its too late to fart about with looms now, when i get back from school tomorrow i may get round to it if i can be arsed Link to comment Share on other sites More sharing options...
wild foamy Posted November 25, 2008 Author Share Posted November 25, 2008 took the tank off and stripped back as much of the shitty electrical tape as i could, can't find any evidence of a solder joint, methink a previous owner has re-done the wiring as there is a bullet connecter on the yellow wire but other than that i got the yellow wire coming out of the bottom of the HT coil going to the brake light, and two black ones which then bundle into the rest of the loom... this bike is starting to piss me off ever so slightly... Link to comment Share on other sites More sharing options...
Moderator Cynic Posted November 25, 2008 Moderator Share Posted November 25, 2008 Why did you not check using the battery and some wire like i suggested instead of ripping into the loom? The yellow is powering the ig coil and the brake lights and we know all that works, the BLUE one is the one you want and that starts at the headlight, as in a connection behind it, and runs to the tail light do not pass go do not collect your 2oo quid. You can check the continuity as you can get at both ends to prove it, you have proved the tail light. If you find this to be ok we can move on. A dodgy taillight is nothing, when i was greenlaning my 175 regular i was going through em all the time, smashing them or filling them and the bike (and me i suppose)with sh1t. And i mean sh1t, cow and horse probably and nothing f'ks your bikes more delicate components quicker. Link to comment Share on other sites More sharing options...
Moderator Airhead Posted November 25, 2008 Moderator Share Posted November 25, 2008 I agree, loom problems should be properly diagnosed using the continuity test on a multi meter, If i had a light out, i would want the loom to be the last place the fault would be, therefore i would prove it before rushing in with a craft knife Do the continuity tests and jumper to the lights male bullets (leave the black in) as has been said Link to comment Share on other sites More sharing options...
wild foamy Posted November 25, 2008 Author Share Posted November 25, 2008 went to the shed and put a 12v 21/5w bulb in it and away it went... will go into town during the week and get a 6v bulb turns out the 5w filament was cream crackered on the original 6v 21/5w bulb despite the fact the filament looked alright i didnt like the look of the original electrical tape that was caked in crap so to be neat i stripped as much of it off as i could and replaced it with fresh tape, now looking a bit better problem solved P.S. i did a continuity test and wasnt getting a reading across the yellow wire that runs my running lights as when i unplugged it the brake light still worked, but when i unplugged the blue one nothing worked Link to comment Share on other sites More sharing options...
Moderator Airhead Posted November 25, 2008 Moderator Share Posted November 25, 2008 You should have a spare bulb, so try that one. went to the shed and put a 12v 21/5w bulb in it and away it went... will go into town during the week and get a 6v bulb turns out the 5w filament was cream crackered on the original 6v 21/5w bulb despite the fact the filament looked alright You would have saved a lot of time and trouble if you had done what i said with my first response, theres no way anyone can say for sure that a bulb is good just by looking at it!, You should carry a spare anyhow so youre not stuck when this happens. Link to comment Share on other sites More sharing options...
wild foamy Posted November 25, 2008 Author Share Posted November 25, 2008 lesson learned the hard way... also learned which is reserve on the fuel tap the hard way... pushing a motorbike 5 miles to the nearest petrol station in the pitch black on the back roads is a very scary thing Link to comment Share on other sites More sharing options...
Moderator Airhead Posted November 25, 2008 Moderator Share Posted November 25, 2008 lesson learned the hard way... also learned which is reserve on the fuel tap the hard way... pushing a motorbike 5 miles to the nearest petrol station in the pitch black on the back roads is a very scary thing i'm surprised at you there Steve, theres only 3 positions and if you ran out and still the other two didnt work its because you were on reserve in the first place Always remember to switch back to main when you fill up, lessons learned best are lessons learned hardest eh! Link to comment Share on other sites More sharing options...
wild foamy Posted November 25, 2008 Author Share Posted November 25, 2008 i thought i was on main ... was a very long walk, took me over two hours non stop Link to comment Share on other sites More sharing options...
wild foamy Posted November 25, 2008 Author Share Posted November 25, 2008 i thought i was on main ... was a very long walk, took me over two hours non stop Link to comment Share on other sites More sharing options...
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