Headlight problems, help please?!

[hamzamian]

Hi,

The headlights on my wife's MX-5 seem to be behaving more than a little erratically...

About a week ago I noticed that the passenger side headlight wasn't working, no problem I thought; just change the bulb... but the next day it started working again of its own accord. So last weekend I thought I'd take the bulb out and take a look and change it just in case anyway... but it seemed completely fine so I left it in.

Yesterday, went to pick up my wife from the station in the MX5 and I noticed that now the driver's side headlight isn't working (but the passenger side IS working). Odd. So while waiting for her to turn up at the station I got a torch out and pulled out the driver's side bulb... and it looks completely fine too. Odd.

So I checked the fuses and both LH and RH fuses in the fusebox in the car were intact. Odd. Wife turned up so I started the car again... and now both headlights have stopped working!

Great.

So any ideas or any obvious faults to look for before I pull out the multimeter and start trying to chase down some dodgy wiring or relays?

Thanks!

[MrV]

Try checking the earth,I seem to have a faulty one at the moment that is proving hard to track down but it is the root of my light problem.

[Joem]

Does the blue full bean light on the dash partially light up when the lights are on? I had fun and games with intermittant lights for ages. turns out that the spade terminals which attach to the bulb were corroded and were trying to light both filaments at once. this lead to shortings like yours.

[hamzamian]

Joem said:

Does the blue full bean light on the dash partially light up when the lights are on? I had fun and games with intermittant lights for ages. turns out that the spade terminals which attach to the bulb were corroded and were trying to light both filaments at once. this lead to shortings like yours.

Was exactly this and one of the bulbs had actually failed now. Decided to take a look over lunch and it was some corroded/melted terminals on the H4 bulb connector on the passenger side.

Cut off the old connector, put on a new one and two new bulbs and its all working exactly as it should now.

[trace1967]

Hi, I had a headlightproblem, the drivers side bulb was yellow and the other white. Checked bulb was ok. checked the plug and the terminals melted My earth was re-scraped and now the problem has gone but had to get a new terminal from autolink.

Hope this helps