New bulbs but lights still dim
03-05-2012, 01:47 AM
#1
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New bulbs but lights still dim
Hi All,
New member, but have previously browsed and found wghat I needed!
I noticed recently that my headlights were dangerously dim (dipped beam especially) so I bought some new bulbs (extra bright but not illegal) on changing the bulbs, the light does appear brigher, but still gets 'drowned out' by cars coming the opther way!
I did wonder whether the battery might be to blame, so I connected the battery from our other car to mine (as if jump starting) which had no effect.
The dipped bulbs are behind a focusing lens, which still seems fairly clear so I doubt that this is the problem...
Does anyone have any advice what I should try next?
Thanks!
New member, but have previously browsed and found wghat I needed!
I noticed recently that my headlights were dangerously dim (dipped beam especially) so I bought some new bulbs (extra bright but not illegal) on changing the bulbs, the light does appear brigher, but still gets 'drowned out' by cars coming the opther way!
I did wonder whether the battery might be to blame, so I connected the battery from our other car to mine (as if jump starting) which had no effect.
The dipped bulbs are behind a focusing lens, which still seems fairly clear so I doubt that this is the problem...
Does anyone have any advice what I should try next?
Thanks!
03-05-2012, 04:35 AM
#2
AudiWorld Super User
halogen or HID?
Have you had your eyes checked for cataracts? (Not being facetious....it happens...)
Have you had your eyes checked for cataracts? (Not being facetious....it happens...)
03-05-2012, 06:53 AM
#4
AudiWorld Super User
Old reflectors...sometimes the shiny isn't.
The other problem isn't necessarily your battery....hooking up another battery in parallel to yours isn't going to affect the voltage/current delivered to your bulbs.
Historically, the wiring to OEM halogen bulbs is barely adequate to deliver full voltage at operating current draw to those bulbs. The current has to go from the battery through the headlight switch (and all the wiring between) and then to the headlights...there may be a relay or two between but the wiring from the battery to the relay and the relay to the light is often too small. V=IR, or what happens is the resistance in the wire times the current draw generates a voltage drop across the wire, thereby limiting the voltage delivered to the bulb.
Further, the lowered voltage causes the bulb to draw MORE current (the bulb is rated at 55 watts, lower voltage means more current for the most part, other factors will come into play but I digress) which means more voltage drop in the line. Bulb brightness/output is related to voltage.
Sooo, you might look at (1) the reflectors...are they dull, dirty, etc. Often the reflectors can't be polished without removing the micron-thin coating, they don't use metal anymore, it's a vapor deposit on plastic, and
(2) Check the voltage to the bulb AT the bulb with the bulb lit. If it's lower than 13.8v or more than .3-.4v less than battery voltage, you need to wire in relays and heavier wire.
The other problem isn't necessarily your battery....hooking up another battery in parallel to yours isn't going to affect the voltage/current delivered to your bulbs.
Historically, the wiring to OEM halogen bulbs is barely adequate to deliver full voltage at operating current draw to those bulbs. The current has to go from the battery through the headlight switch (and all the wiring between) and then to the headlights...there may be a relay or two between but the wiring from the battery to the relay and the relay to the light is often too small. V=IR, or what happens is the resistance in the wire times the current draw generates a voltage drop across the wire, thereby limiting the voltage delivered to the bulb.
Further, the lowered voltage causes the bulb to draw MORE current (the bulb is rated at 55 watts, lower voltage means more current for the most part, other factors will come into play but I digress) which means more voltage drop in the line. Bulb brightness/output is related to voltage.
Sooo, you might look at (1) the reflectors...are they dull, dirty, etc. Often the reflectors can't be polished without removing the micron-thin coating, they don't use metal anymore, it's a vapor deposit on plastic, and
(2) Check the voltage to the bulb AT the bulb with the bulb lit. If it's lower than 13.8v or more than .3-.4v less than battery voltage, you need to wire in relays and heavier wire.
03-05-2012, 10:58 PM
#7
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Thanks! Gives me somewhere to start!
Old reflectors...sometimes the shiny isn't.
The other problem isn't necessarily your battery....hooking up another battery in parallel to yours isn't going to affect the voltage/current delivered to your bulbs.
Historically, the wiring to OEM halogen bulbs is barely adequate to deliver full voltage at operating current draw to those bulbs. The current has to go from the battery through the headlight switch (and all the wiring between) and then to the headlights...there may be a relay or two between but the wiring from the battery to the relay and the relay to the light is often too small. V=IR, or what happens is the resistance in the wire times the current draw generates a voltage drop across the wire, thereby limiting the voltage delivered to the bulb.
Further, the lowered voltage causes the bulb to draw MORE current (the bulb is rated at 55 watts, lower voltage means more current for the most part, other factors will come into play but I digress) which means more voltage drop in the line. Bulb brightness/output is related to voltage.
Sooo, you might look at (1) the reflectors...are they dull, dirty, etc. Often the reflectors can't be polished without removing the micron-thin coating, they don't use metal anymore, it's a vapor deposit on plastic, and
(2) Check the voltage to the bulb AT the bulb with the bulb lit. If it's lower than 13.8v or more than .3-.4v less than battery voltage, you need to wire in relays and heavier wire.
The other problem isn't necessarily your battery....hooking up another battery in parallel to yours isn't going to affect the voltage/current delivered to your bulbs.
Historically, the wiring to OEM halogen bulbs is barely adequate to deliver full voltage at operating current draw to those bulbs. The current has to go from the battery through the headlight switch (and all the wiring between) and then to the headlights...there may be a relay or two between but the wiring from the battery to the relay and the relay to the light is often too small. V=IR, or what happens is the resistance in the wire times the current draw generates a voltage drop across the wire, thereby limiting the voltage delivered to the bulb.
Further, the lowered voltage causes the bulb to draw MORE current (the bulb is rated at 55 watts, lower voltage means more current for the most part, other factors will come into play but I digress) which means more voltage drop in the line. Bulb brightness/output is related to voltage.
Sooo, you might look at (1) the reflectors...are they dull, dirty, etc. Often the reflectors can't be polished without removing the micron-thin coating, they don't use metal anymore, it's a vapor deposit on plastic, and
(2) Check the voltage to the bulb AT the bulb with the bulb lit. If it's lower than 13.8v or more than .3-.4v less than battery voltage, you need to wire in relays and heavier wire.
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