New Build Wiring Question - No lights at all !!!

[harps2]

Hi

Just finishing off rebuilding LI150 Special - converted to 12V Electronic Ignition (No Battery)

Checked spark and looks really healthy so hopefully that end of Electrics OK

Wired headlamp connector up and checked by using 12V charger joined to brown wire at regulator end of loom but no lights at all --- headlamp , tail, festoon, speedo all NG, and horn gives a blip (popp) when pressed so seems something fundamentally wrong here me thinks??? - followed stickys wiring diagram as good as possible and basically most wires are just colour matched up in headlamp connector - any suggestions please??

Thanks in advance

[hullygully]

if the horns blipping, check your earths, don't use st/steel bolts, remove paint where necessary

[dickie]

if the horns blipping, check your earths, don't use st/steel bolts, remove paint where necessary

Why not use stainless steel bolts?

[grandpa]

Hi Harps
If you have an AC horn it will not work well if harness is connected to a battery charger which is DC

Grandpa

[harps2]

So do you think it is earth problem that none of the lights are working Grandpa?

[Meds]

Did you connect in before or after the regulator?

[Tractorman]

Tracing wiring faults is about following the wires through so you have connected to the battery charger, silly question is the charger negative wire connected to clean point. If all is well is power getting to the other end of the brown wire? Then with the wire plug into the terminal block is there power at the other connections. This may seem a waste of time but years of tracing tractor electrical faults has taught me to be methodical.

[grandpa]

Hi Harps2
1 check battery charger will light up say a festoon bulb or headlamp bulb ,some chargers need a load to switch on
2.charger negative to frame earth
3.charger positive to harness after regulator as Meds suggests via a 5amp inline FUSE. if you don't have inline fuse use fuse wire and a terminal block(25 watt lamp uses just over 2 amp at 12volt)
4. check for 12volts at headset ,start with speedo bulb or festoon .Headset lamp holder must have an earth .A length of wire to hold against earth side of festoon and main frame may be useful.
5 remember if no brake pedal fitted brake light will stay on.
6 hope you have a multi meter analogue type are better for diags (with needle) set to 20volt dc if using charger needle should move just over half way) If you don't have meter try a 12volt bulb with two wires attached .(H4 car headlamp has three "prongs" where you can wind some wire on (pound shop)

Hope this is of some help ..off to France soon on hols don't know if there is WiFi..........Don't forget the fuse wire
Grandpa

[harps2]

Thanks to all for the advice to date (especially GRANDPA) - we are progressing so I now have all front lights working correctly, but still have some issue so here goes:-

Brake light works OK except when ign is in "lights on" position then no brake light!
Rear running light does not come on at all

so still some work to do ............... as ALWAYS any advice welcome as I imagine some of you experienced guys have had similar issue before!

[hullygully]

if the horns blipping, check your earths, don't use st/steel bolts, remove paint where necessary

Why not use stainless steel bolts?

I meant don't use st/steel bolts as your earthing point der

[Wack]

Firstly check the rear light unit has a good earth,I always use these after removing some paint https://www.ebay.co.uk/itm/BZP-EXTERNAL ... vz16W_KWpw The rear light gets it's power from the ignition switch black so check you have power coming from the switch wire and that the connector block has continuity thru it ,the speedo bulb should light up when earthed.The brake circuit is completely separate from the other wires in the loom,unless you have used the original loom and joined all the wires together so there is either a short or bad earth.

[grandpa]

Hi Harps2
Black wire feeds rear lamp ,if Speedo bulb works you could plug black wire into Speedo bulb position to check rear lamp.
If still running off charger remove headlamp bulb and see if festoon bulb still works when brake activated because charger may only be giving low amps ( brake light 21 watt plus headlamp 25 watt is 46 watt which is almost 4 amps)Bad earth's as others have said cause weird faults
Many Lambrettas will dim headlight when brake activated that's why Wassell mod with battery is so good

Good luck
Grandpa.

[harps2]

right well still having problems - very frustrating these blloody electrice!!!


All front lights working headlamp low/high, festoon and speedo - that's good except brake light works in all positions except last ign position which is lights on!
Rear running light not working at all, changed connector for rear light to speedo bulb position still no good , tried new wire from speedo bulb position to bulb holder - no good - going to fit serrated washer and improve earth - so close but so far !!!!

[harps2]

To all especially Grandpa and Wack - its sorted so thanks very much for your help m- much appreciated - serrated washer on back light earth sorted it so now its off for MOT - thanks again !!