Technical Question . Light on a 1100 GS

[Geno]

We had our MOT today , so was getting headlight set up , was told it was dim , so changed bulb and took her to test . Tester also commented on it been very dim , my question is what has happened to the light ?? What can I check or replace ,? Any relays or switches I can check .? Thanks in advance . Geno

 

[Fanum]

Check the earth connection....
Remove bulb from socket, and if you can take the assembly apart, rub a bit of fine sandpaper across the part of the holder that makes contact with the earth connection. (or you may be able to poke the thin end of an emery board in there)

Also check that the spade connectors to the bulb holder (especially the earth) are in good condition (not crudded up with green gunk) and then replace the bulb and see if it's brighter.

It is possible that it's elsewhere in the circuit, but it's nearly always just a bad earth contact in the bulb holder

 

[Bubb]

I think poor earth too.....

a small amount of corrosion is normal in anything used in the UK.... and electrickery makes it worse , and will drop the power available to emit light.

Think you will manage to fix it easily with Fanums instructions

 

[Geno]

I tried cleaning the holders but no change in light . Anything else I can try ?? Can I fit a brighter bulb ??

 

[Delboy777]

I tried cleaning the holders but no change in light . Anything else I can try ?? Can I fit a brighter bulb ??

I wouldnt think so. If there is a problem it will need to be fixed otherwise it will only get worse.

 

[MikeO]

Put your meter across the bulb socket - what voltage is the bulb getting?

 

[Geno]

Will do that next . Won't be till I get time to put front wheel back on ,it's get new tyre . I will drop you a line . Thanks for help

 

[Geno]

I have tried all connections, cleaned all I can , headlight still very poor , main beam is working 100% . What else can I check ? Fitted a fuse box for the extras ,light , GPS , Auto Com . Any more ideas . Thank you all .

 

[DrFarkoff]

Sorry to ask but are you sure you have the Connector on properly as in 3 prongs lined up I have seen this happen when someone fitted the plug 90 degrees out of kilter and only two circuits of three were being used

Bulb should be a "472" 12 volt 50/65W in case some one has given you a 24volt version

If all is good there Drop the handlebar switches off and ACF50 the back of them

Don;t dismantle the switches just remove the from the bar and spray ACF into the back of them and operate them a few times to allow the ACF to soak in

 

[Geno]

The bulb I have taken out , 60 / 55 , 12 volt . Can't make out anything else . Thank you for help . Next time we meet I will be getting you drunk ,I owe you .

 

[Fanum]

Try connecting the bulb DIRECTLY to the battery, just to see if it lights up properly.

If it does (almost certain) then you have a problem with the circuit not passing enough current......that could be in the connections, in the switch, the wiring or the earth point.

If you have a DMM, you can test the circuit by looking at the resistance at various places, starting from the battery then working to the switch, then to the back of the bulb etc, until you find a place where there is high resistance. (which could be a rusty wire inside its sheathing, a poorly crimped connection, a wire where some or most of the twisted strands have become broken etc.)

If you're not confident with a DMM, you can try using a fresh length of wire and effectively by-passing the parts of the circuit.....EG go from battery live to the back of the bulb IN SITUE.......that bypasses the switch and everything inbetween the battery and the bulb.....if it's STILL dim, it means the crap bit of the circuit is beyond the bulb and probably at the earth point.....to confirm that for sure, you then put the fresh wire from the bulb earth terminal to the battery earth pole.......then the bulb should be bright.

Approach it logically and step by step and you should be able to track down the problem

 

[DrFarkoff]

What about this bit are you sure you have the 3 bulb prongs entering correctly into the 3 spades??

An Experiment for you Carefully clean back a spare bit of wire and push it into the hole with the brown wire on the headlamp socket

Turn on the light and ground the other end of the wire to for example the exhaust

Does the light get brighter?

Sorry to ask but are you sure you have the Connector on properly as in 3 prongs lined up I have seen this happen when someone fitted the plug 90 degrees out of kilter and only two circuits of three were being used

EDIT I Suggest a 5 amp (10 amp maximum!) fuse fitted inline of your grounding wire just to be safe