puzzled headlights on car ?

[John Hardy]

hi
on my normal headlight there is 13v of power soon as i connect the wire to the bulb power drops to 0 ?

 

[DPG]

On the off-chance that this isn't a wind-up: Is this while it is in the car, or are you testing the lamp on it's own? Daz

 

[John Hardy]

3 wires to bulb still in car ,earth wire ok , 13v on high beam wire ok and works when connected to bulb , but ? 13v on main headlight wire but if i touch the right connection on bulb it drops to 0v lamp if fine if i just put 2 wires straight to battery , just wondering why my live headlight wire drops to 0v when i attach it to my light but the battery live is fine

 

[DPG]

Do same test using headlight bulb from other side of car. Eliminate/home in on the problem. Do a resistance test on the bulb and compare to the other bulb. Let us know what you find and we'll go from there. Daz

 

[John Hardy]

both sides do it only way to make headlights work for now is to run a live to battery and a new switch inside and it works fine

 

[John Hardy]

just wondering while im testing it and headlight switch is on the wire shows 13v but soon as i touch the right terminal on back of bulb it drops to 0v i know its not the earth as my high beam works perfect

 

[telectrix]

sounds like a poor connection 13V with no load, but as soon as you put a load on it, it drops to 0V.

 

[DPG]

Agree with Tel on this one, poor connection somewhere. Could be switch itself of course. Can you get any switch cleaner/WD40/etc. inside the switch? Daz

 

[telectrix]

ARRRRGH... the dreaded fix all bugger it up spray.

 

[DPG]

Nowt wrong with the old WD ! Daz

 

[John Hardy]

i got another light switch stalk and still the same and replaced relays ? and fuses

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if this helps it a mk4 escort loads of ppl with same prob but no answers

 

[telectrix]

geordie spark is close to you. he's good with cars. he's got 3 that won't work. :speechless:

 

[John Hardy]

sounds just the right lad lol does he want 4

 

[John Hardy]

i dont understand electrics just basic . just wonder y it would say 13v but soon as i attach it to bulb nowt ?

 

[John Hardy]

i just dont understand why it reads 13v then soon as i put it on bulb 0v

 

[Brendan976]

You probably have a loose/corroded earth and it is only showing up when you put a load on the circuit, bolt on a new earth cable to the battery and connect the other end onto the outer metal work of the lamp holder if this works you will need to identify the earthing points on the car clean them up. Now try again,but this time remove your temp cable, if this works jobs a good un if not get a copy of wiring diagram you will need to trace them out for continuity, disconnect battery but make sure you have your radio code first
Hth
Ben

 

[telectrix]

i just dont understand why it reads 13v then soon as i put it on bulb 0v

the feed may be coming through a bad connection. with no load and therefore no current flow this may show 13V on your meter. as soon as you apply as load, current will not flow through the poor connection due to high resistance and so the load end of the supply will read 0V as it's tied to 0V through the lamp.

 

[ruston]

The Escorts were notorious for the leads rotting off the fuse boxes, in fact the wiring was poor at best. If it doesn't work it has to be bad connections , the stalk wasn't the best on them either , so fuse box ,stalk , and as said earth may be a good starting point.

 

[tazz]

Loads of problems with fords around 2004, all faults with headlights have been down to cable and multiplug behind the fuse board melting, bypass multiplug on mine with 1mm autocable all fine now. Was grateful to Mondeo forum for the info

 

[telectrix]

thing is, with cars/vans, during the late 80's manufacturers had to bow to pressure to stop them deliberately making cars that rotted away in 5 years or less. then they had to come up with a means of making motorists scrap their cars as uneconomical to repair. enter crappy cam belts and engine management systems. guaranteed to break within 3 years and a monthor 30,001 miles