Main Beam not working one side

[Bluebottle]

Just replacing my nearside driving lamp after a stone smashed it at the weekend and now it won't work.

Ok i'm a numpty when it comes to electrics, but having repaired the wiring (corroded connectors), I got a 12v reading on my digital gauge. But, as soon as i connect them to the bulb it drops to zero and bulb doesnt light up (bulb is good)?!

[Loubaruch]

Looks as though you have a high resistance somewhere in the circuit. If the lamp was working OK before it was smashed it must be something you have done after the event. Try cleaning the contacts again.

If this does not cure the fault:
Identify the earth lead and connect a wire direct from Battery +ve to the other side of the lamp If it now lights the +ve wiring is faulty. Make sure you identify the earth otherwise there could be a big bang! if you get it wrong.

If this does not work run a wire from a good earth or battery -Ve and connect to the earth side of the lamp If it now lights the earth wiring is faulty

Best of luck!

[Argent]

I would say that is a perfect opportunity to re-wire your lights with heavier gauge cable, I did it on my last Griff and it made quite a difference to the output.

A

[cavebloke]

Argent said:

I would say that is a perfect opportunity to re-wire your lights with heavier gauge cable, I did it on my last Griff and it made quite a difference to the output.

A

Is there a "How-To" guide for doing this anywhere to assist the electrically inept?

[ruaricoles]

Not long after I got my Griff I was doing some work at the front end and found the headlamp wiring was clearly getting too hot - signs of slight charring in the insulation - and the cables were clearly too small. If I remember right, I used the original power cables to switch relays, put the relays under the lamp pods and took power instead from the starter motor or some other handy point with a fuse and better cable. I also fitted better bulbs, and remember the revelation at actually being able to see (something!) in the dark. This might be an easier option than stripping out the original power cable and replacing it all with new.

I've now also got the 7" lamps (fitted for me by Sportmotive) which is another step again in the right direction.

Ruari

[Bluebottle]

the offside has now stopped working as well
Oh well, looks like I'm going to have to wrip out my crispy fried spaghetti and run new cables into the nose.
what would be suitably sized wire for the headlights, and would you wire it the same as before do as above?

[Hoover.]

had an issue like this a few years ago which required cables on the rear of the fuse board replacing

[Argent]

I don't remember what gauge cable I used but this link might be useful. The cable mod with the high output bulbs is a great upgrade if you don't want to go all the way of putting in the larger headlight pods or HID.

http://www.djbeer.hostingbt.com/id21.html


A.

[tivver500]

Don't be fooled by the physical size of vehicle wiring. Older type 1 sq mm wiring can now be replaced by 0.5sqmm thin wall insulated cable which is good for about 10amps. More than suitable for a 60watt headlamp bulb (5amps).
Wiring itself is rarely the cause of problems.
The main cause is the connections between the wires. Examine ALL of these, clean and lubricate and a lot of your (electrical) problems will go away.
Happy tivving.....

[BliarOut]

Just use the original wiring to fire a relay with it's own feed. Dead easy

[Bluebottle]

BliarOut said:

Just use the original wiring to fire a relay with it's own feed. Dead easy

thats the problem, it is carrying voltage, but not enough current, it cant even light a bulb, much less hold a relay open.
I had this problem a few years back an i know Dulford's re-wired some of the lighting circuit in the nose area due to the wire decaying internally. my fear is that the wiring has now degraded further up into the wing

[BliarOut]

Can't you wire a relay to feed the relay?

[Bluebottle]

the wiring for the main beam headlights has been in decay for several years and at some stage the garage has spliced new wiring to power the lights. the nearside has 3 wires in and one neg...but no power, the offside has a thin wire spliced in on the pos side and that is feeding it power.
So i have run a new fused live from the alternator to power both lights through a relay. Using the wires to the the offside to switch the relay.
how do i connect the existing wires to the relay such that they don't blow the fuse on the fuseboard when i switch main beam on? I am assuming it needs some sort of resistance or something but i bought a resistive relay or at least i thought i had ?!?

[LordGrover]

It'll probably be an upgrade on standard high-beam too. Win-win!

[Bluebottle]

LordGrover said:

It'll probably be an upgrade on standard high-beam too. Win-win!

lol, i just spent most of the day under the car wearing one of those trying to sort out the spaggetti...and you are right it lights up the back wall of my garage far better than this bloody bath tub does.

[BliarOut]

Just wire the lights in parallel from the relay. You can get dual pole relays designed for the job. It's dead easy to run extra wiring in under the nose on these old tubs

Fused wire from alternator goes to dual pole relay, old switching wire goes across the coil, each light gets a live and earth of its own.

[Bluebottle]

That's how I wired it up, but it blows the fuse as relay is making a short circuit when connected to pins 85 & 86 , so have I got the wrong sort of relay?

[BliarOut]

http://www.the12volt.com/relays/relays.asp

Fig 5

New fused feed goes on 30, 87 and 87 b go to each light, each light goes to earth.

Old switched feed goes to 85, 86 goes to earth. Can wire those two either way round tbh.

[Hoofa]

Hey up rob a dual trader

[BliarOut]

Good apprenticeship

When did you change your name, I had to do a double take there



If it pops when wired like that disconnect both 87's and check the relay latches (12v from either pin to earth).