hey whats up guys i was wondering if anyone can help me? my HID headlights keep going on and off while the car is on. One will go off then i can turn the lights off and on again and the lights will pop back on SOMETIMES? i measured it with meter when i bought the new battery, it fluctuates between 13.4 and 13.7. Im wondering if it is my alternator going out or what. im about to pull the alternator out and have it tested, its the only thing i can think of that would make this happen the HID lights are new, but im no mechanic,ha! If anyone can give me an opinion that would be greatly apreciated, THANKS!
No, your alternator is perfectly fine. FSM states the alternator needs to put out 13.2-14.8vdc, and fluctuating between 13.4 and 13.7 is good. If anything, your battery may be aittle low on a charge(should be 12.6vdc or more after the car has been off over 8 hours). It may also be alittle low from sitting on the shelf. I just put a brand new 800CA Optima battery in my car which reads 13.0 volts car off, but when my car is running and there is a decent load on the car(headlights, fogs, a/c blower), my voltage is 14.2 volts when the engine is cold, but then drops to 13.5 when the car reaches operating temperature. I think your headlight issue is irrelavent to the headlights going on/off. It sounds like the bulbs are at the end of their lifespan. that's what usually happens, they turn off and may turn back on when the power is cycled. In most cases, a badballast will never even ignite the bulb. I would try swapping the bulbs with each other to see how they react, but it really does sound like they are ontheir way out. for future reference, here's a DIY for the charging system i made awhile ago which may help you because there are a few tests you can do before having it bench tested. BTW, i would stick to a good bulb replacement brand like sylvania, philips, ospram, etc.
hey thanks alot jason so i should try new lamps huh? i hope that is the case i thought once lamps go out they go out i didnt know they slowly go out like that, well thats alot better than dropping the alternator. ill try this any links to lights that are good?
Yea, when they start to go bad sometimes they turn a bit purple when trying to ignite and then they go off and power needs cycled. You can get em off eBay, just make sure its a reputable seller. My buddy's gotten bulbs from autoillumination.com and xenonsupply.com with good results. I would highly doubt both of your ballasts are going bad. Those OEM Denso ballasts are the best IMO. You may also want to check our vendors section for good pricing. Remember not to touch the new bulbs with your bare hands, the oils on your skin can reduce their lifespan. Good luck.
if it didnt do it before changing the battery I would start there make sure all the connections are solid.. and then from there you might want to make sure the relay is good. other wise like said before could be your lights. what year is your car and have you changed out the lights before?
FUDGE! put in new hid h7 lamps and they are still going out? Do you think its a relay or what? i bought new battery new lamps and they still go out either one at any given time. all the wires are new and great shape. could it be the ballasts one of these dudes at the shop tried to sell me on some ballasts but im just not sure if there bad? what to do ANY HELP WOULD RULE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Did you ever try swapping the bulbs with each other and they still would shut off? The only other thing it can be is a lack of power to the ballasts or the ballasts themselves. I would get a voltmeter and verify you are getting full battery/alternator voltage to the headlights when the car is running. If you read alittle low then you may have a faulty headlamp relay. If the battery voltage is good and there is still issues, then its the ballasts or connections to them/bulb.
the battery is brand new and so are the lamps i put in yesterday. the relay looks fine, but i dont know what it would look like if it was broke? it does click pretty loud when i turn on the lights though? so ballasts or relay huh? my alternator is good im sure
The clicking of the relay means the coil is good but the contacts need to be tested with a meter for it to definitely be good. I would verify the connections as well.
Well yea, the way to test them is with a voltmeter , energize it, and check for continuity. Or swap it out. I've stuck a needle in the socket to check for voltage before. Obviously if they go out you want to check for voltage feed to make sure.
Throwing parts at it is not good approach especially when the OEM Denso ballasts are probably good. Sounds like a voltage, connection, bulb problem IMO.
im gonna buy a new relay, cuz i already installed new battery and new lamps, everything is solid the after market headlights are like 6 months old, the wiring seems perfect, im hoping its the relay
Last edited by djrighthooks; 08-08-2011 at 10:47 PM.
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