Jake Posted October 29, 2004 Share Posted October 29, 2004 On the way to work this morning I noticed that I only had one headlight working. I meant to have a look at it later but I forgot. I've just been to go out, put the lights on and bugger me, the other one came on for like one second and then went out as well! I've checked the two 15 Amp fuses and they're both fine so I guess the bulbs have blown. What would cause that? They're quite new bulbs. Both were fitted about two or three months ago when I installed the UK headlights. I had a simiilar problem on a motorbike once and it turned out to be the silicon rectifier (iirc, does that sound right?) had blown. Is there something like that on our cars? Thanks Quote Link to comment Share on other sites More sharing options...
CJ Posted October 29, 2004 Share Posted October 29, 2004 Would water ingression do that? Quote Link to comment Share on other sites More sharing options...
Jake Posted October 29, 2004 Author Share Posted October 29, 2004 I don't know. Before this morning the car hadn't been used or even started for a week. Quote Link to comment Share on other sites More sharing options...
CJ Posted October 29, 2004 Share Posted October 29, 2004 I just wondered if the severe weather may have had an impact? Quote Link to comment Share on other sites More sharing options...
dangerous brain Posted October 29, 2004 Share Posted October 29, 2004 Unless the bulbs were particularly crap then you really couldn't expect them to pop their cork in a 2-3 month time frame. Quote Link to comment Share on other sites More sharing options...
Jake Posted October 29, 2004 Author Share Posted October 29, 2004 ...and even then, for them to both go on the same day is too much of a coincidence Quote Link to comment Share on other sites More sharing options...
dangerous brain Posted October 29, 2004 Share Posted October 29, 2004 Yeah very much so.. I would start looking for dodgy earths to start with as they seem to be the root of all electrical evils. After that you are kind of looking for other things that can cause power spikes in the lighting only circuit. Electrics why is it its not as simple as seeing a leaky substance? Quote Link to comment Share on other sites More sharing options...
Red Posted October 30, 2004 Share Posted October 30, 2004 Its a tricky one with them both going together. If they are protected by properly rated fuses then you'd think a power spike/surge would blow the fuses - as thats what they're for isn't it?? what is the ampage on your new bulbs?? maybe one of the bulbs was weak and blew - and the increased current going to the other one (I often see cars with one light out showing a brighter than 'normal' remaining headlight) sent the other one on its way??? Just a suggestion, hope you get to the bottom of it mate. Quote Link to comment Share on other sites More sharing options...
LeeT Posted October 30, 2004 Share Posted October 30, 2004 Originally posted by Red Its a tricky one with them both going together. If they are protected by properly rated fuses then you'd think a power spike/surge would blow the fuses - as thats what they're for isn't it?? what is the ampage on your new bulbs?? maybe one of the bulbs was weak and blew - and the increased current going to the other one (I often see cars with one light out showing a brighter than 'normal' remaining headlight) sent the other one on its way??? Just a suggestion, hope you get to the bottom of it mate. AMEN Quote Link to comment Share on other sites More sharing options...
Whitesupraboy2 Posted October 30, 2004 Share Posted October 30, 2004 either that, or basically what happened to my old escort!! the metal on the bulbs, built up a nice layer of condensation to the consitancy of water! then popped them when i turned them on. Coule easily be this or what Red said Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted October 30, 2004 Share Posted October 30, 2004 El Cheapo bulbs or the alternator regulator is up the creek. measure battery voltage on and just after start up, should not exceed about 13.8 volts. Cheap bulbs, or thsoe silly coloured / mega wattage ones can ciause issues, too. Quote Link to comment Share on other sites More sharing options...
Jake Posted October 30, 2004 Author Share Posted October 30, 2004 Thanks Chris. I'll check the battery voltage tomorrow. Is the alternator regulator something inside the alternator or something that can be replaced seperately? By the way, both bulbs had blown when I checked today. Quote Link to comment Share on other sites More sharing options...
dangerous brain Posted October 31, 2004 Share Posted October 31, 2004 Originally posted by Jake Thanks Chris. I'll check the battery voltage tomorrow. Is the alternator regulator something inside the alternator or something that can be replaced seperately? By the way, both bulbs had blown when I checked today. As in both blown again? Quote Link to comment Share on other sites More sharing options...
Jake Posted October 31, 2004 Author Share Posted October 31, 2004 Originally posted by dangerous brain As in both blown again? No. I meant the reason the lights weren't working was that the bulbs had blown. I hadn't actually had the bulbs out to check when I started this thread. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted October 31, 2004 Share Posted October 31, 2004 Originally posted by Jake Thanks Chris. I'll check the battery voltage tomorrow. Is the alternator regulator something inside the alternator or something that can be replaced seperately? By the way, both bulbs had blown when I checked today. Both regulator and rectifier are internal. Quote Link to comment Share on other sites More sharing options...
jagman Posted October 31, 2004 Share Posted October 31, 2004 Just for info fuses will take about 4 times their rating for a brief moment (dependent on the ambient temp) and the amount of extra current so your 15 amp fuses could pass 45 amps for a very short time -enough to take out your headlights as chris said , the voltage reg in the alternator could be playing up or the brushes in the alt sparking/worn out causing the volts reg to throw a wobblie,most alts have a surge diode in them to prevent more than 18 volts( I dont know if the supe has one) The thing is you may check the o/p volts and its fine,until it spikes again -yet another set of headlight bulbs if they are switched on whilst the volts spike( headlights are more susceptable to blowing cos they are one of the hottest and heaviest loads on the car)-- then again it could just be cheap bulbs -- I know a recon alt replacement may be a pain /expense , but so is new bulbs,and fried battery Quote Link to comment Share on other sites More sharing options...
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