Brighter headlights

Discussion in 'SN95 V6 Mustang Tech' started by Jessidog, Nov 28, 2010.

  1. My daughter has a 2003 V6 5-speed Mustang and this is my first post on this forum. She would like brighter headlights, which seems to be a common issue. I have read several articles on use of relays and heavier wiring to reduce voltage drop to the headlights with resultant brighter lights. This makes sense if the power goes through the headlight switch and low/high beam switch. It looks like the 2003 does use relays for the headlight circuits.

    Do these models still have voltage drop to the headlights? Would rewiring with heavy gauge wire (10-12g) and new relays (30-40A) make a significant improvement? If rewired to carry heavier current, can higher wattage halogn bulbs be used or will they be too hot for the headlight lens?

  2. IMO, 96-04 Mustangs do not have problems with exessive voltage drop to the headlights. I have serious doubts that installing heavier gauge wire will make any noticeable improvement with stock headlights.

    The 96-04 Mustangs do have issues with burning up headlight switches if too large of aftermarket headlights are installed. In fact, it is fairly common over time for stock headlights to overheat the headlight switch.

    There is a circuit breaking inside the headlight switch that will trip if too large of an aftermarket headlight is installed. This does put an upper limit of 11 amps per headlight (22 amps total).

    Will she be happy with "brighter" headlights or does she want "stupid" bright? If brighter is enough, cleaning the lens and getting a set of brighter than stock lights may do the trick. Esp if both are done at the same time.
  3. Thank you for your comments. The stock headlights are becoming noticeably cloudy, which seems to be mainly on the inside. Can the stock headlights be disassembled to clean and polish the lens on the inside? Are there brighter bulbs that can be safely installed in the stock headlights using the stock wiring? If so, which ones? Or did you mean that the headlight assemblies need to replaced? I think my daughter would just like a somewhat brighter light, not crazy bright.

  4. Once the clearcoat is toast, for me, the entire headlight is toast. Now you'll see some people who have been able to cleanup their headlights, but I think it's a temporary fix.
    Drop in some SilverStar bulbs (that's all I ever ran before going to HIDs) - available at most auto parts stores.
  5. I have Silverstar bulbs in the headlights now (stock wattage). One light is noticeably brighter than the other. My daughter's friends say that it almost looks like the car is winking. Could this have anything to do with headlight alignment? Where can you get headlights aligned?

    I remember measuring the voltage at each bulb about a year ago. The voltage for each light was nearly the same with less than 0.1V difference. However, I remember it was "12. something" and I do not remember if I had the engine running. Shouldn't the voltage be close to 14.5V with the engine running? The next time I have access to the car, I should be able to run a temporary wire from the battery to the headlight and see if there is a noticeable increase in brightness. If so, then modifying the wiring with heavier gauge wires and relays might be helpful. If there is no difference, then rewiring would not provide any benefit. Is my thinking correct?

  6. Silverstars and Clear Cobra Headlight housings should make it bright enough. You can always also add fog/driving lights too.
  7. The headlight restoration kits improve clarity but then the headlights are just never the same. A new set will cost you $100-$200. An on-line purchase will be your very best bet. American Muscle or any other will have a variety to choose from.
    Better quality lamps will be the safest(literally) bet. Ozram "Night Breaker" & Philips "X-treme" will be the very best and brightest you can buy without an increase in amperage. Lamp life longevity is sacrificed though. Never had one burn out pre-maturely on me before. These lamps most likely purchased on-line. Ozram or Sylvania Silver Star Ultra's can be purchased at any parts store.
    Hope that adds to info needed. Good luck and have fun! But watch out because this is the exact same first mod I needed and then it turned into something out of control like mine did!! Ha!!!:lol:
  8. Do NOT get Silverstars or any other tinted or coated bulb. Stay with clear bulbs. The light output from the Silverstar only appears whiter, its not brighter than the clear GE Nighthawk and Sylvania Xtravision bulbs. They are about the best bulbs you can find. They are also not over wattage. I would also use some type of relay setup and clean the lights. This stuff called Crystal View works well for restoring headlights.

    Headlight Restoration | Headlight Cleaner
  9. This man is correct! Except about the stay away part. I loved those Night Breakers. Probably would of liked the two you mentioned also. They are all good, trust me.:shrug:
  10. The difference in brightness is a prime symptom of lower voltage. IMO, this is saying there is a dirty electrical connection to the dim headlight. It is either in the bulb socket or in the ground.

    Clean the sockets with electrical contact cleaner. Use silcone di-electric grease (same kind as used on spark plugs) to re-grease the connectors.

    If no improvement, check the grounds.
  11. I've never seen those headlight cleaning kits bring the lens back to new. The best thing to do is buy new headlights. You can find some good deals on EBay- just make sure they are DOT listed if they are aftermarket lights.

    +1 on avoiding blue-tinted bulbs. The eye is less sensitive to blue light, so even if you up the wattage you still won't see as far. IMHO the best solution for good visibility is true HID bulbs (ones with a ballast- not blue bulbs advertised as 'HID-type').
  12. The problem with HID is that the retrofit kits are illegal and for good reason. The optics of the halogen lamps is designed for halogen bulbs. The HID bulbs in a halogen lamp will produce excessive glare to oncoming drivers.
  13. What stay away part?

    I have heard good things about the Night Breaker, Phillps Vision Plus, Phillips Xtreme Power as well. Wagner Brite Lites are decent also.
  14. My daughter is home for the holidays so I have access to her car. With the engine at idle, the voltage from the B terminal on the alternator to the neg terminal of the battery and the voltage across the battery terminals was 14.25 volts. With the headlights disconnected, the voltage between the hot terminal for the low beam and the negative terminal of the battery was 14.23 volts. The voltage across the hot terminal and ground for the headlight was also nearly the same. So I did not think that voltage drop was the problem.

    I reinstalled the headlights and then turned them on with the engine idling for about ten minutes. When I measured the voltage across the two terminals with the headlights on, the voltage was 12.9 volts. So under load, there is about 1.3 volts drop. The drop might increase with longer driving time and more heat build-up. How much of an effect would this have on light output? I have read that the drop in light output can be significant with even small voltage drops.

    If I rewired the lights with heavier gauge wire and relays, could I safely use higher wattage bulbs? Or, would the bulbs generate too much heat and damage the headlight housings?

    Thanks for the help.

  15. Jessidog; Did you CLEAN the connectors with electrical contact cleaner and re-grease with silcone di-electric grease?

    Your reply does not mention if there is still a noticable difference in brightness between the headlights. Nor does it mention if the brightness of the headlights is still a problem (in other words, did cleaning and re-greasing the head light terminals have any effect?).

    Your reply does not mention the condition of the head light lenses. Are they cloudy or yellow?

    The voltage across the headlight terminals seems reasonable to me. FWIIW, because of the current draw, it will never read full alternator voltage.

    Since you have asked for advice, I give you some of mine. I would want my Daughter to be driving a reliable as possible car. For the most part, anytime the car is re-worked away from Ford stock, this decreases the reliability/serviceabilty of the car. For that reason, I would not re-wire the head lights.

    I WOULD repair everything to Ford Stock.

    If the head light assemblies are cloudy, I would be more inclined to spend the $$ on new plastic head light assemblies. The results will look better and the fix will be much easier for you to do.

    With regards to how much the stock system can support. Remember the 22 amp circuit breaker? Per Ohm's law, 22 amps will support 264 Watts (12 * 22 = 264). That 132 Watts per head light. Check the wattage of the possible replacement. If the wattage is less than 132 Watts, it should work fine in the stock Mustang assuming everything is in good repair.
  16. Yes, I cleaned the electrical contacts for the headlights and used a little dielectric grease on the contacts. I also checked the grounds. After everything was reconnected, there was no noticeable difference. The headlight housings are in good shape and do not have the yellow discoloration commonly found on plastic headlight housings.

    The rewiring would involve heavier gauge wires (probably 12 g) from the battery directly to the headlights. The stock wire would be used to trigger a relay. There would be an in-line fuse in the wire powering the headlights so the high current flow to the headlights would not go through the stock wiring and fuse. Only then would I consider a higher wattage bulb. I would not install higher wattage bulbs using the stock wiring. I'm just not sure if the plastic headlight housings would be damaged due to higher heat generation from the higher wattage bulbs.

    The Mustang uses a 9007 bulb that has both the high and low beam in a single bulb. My Miata uses a 9006 bulb for the low beam, which is rated for 1000 lumens. There is another bulb (9012) that is also 55 watts, but is rated for 1870 lumens. It sounds like the 9012 is a more efficient bulb that generates more light with the same amount of energy. I have looked, but have not found a similar bulb to replace the 9007.

    I won't be able to work on the car again until early March, so I have time to do more reading.

    Thanks for the help.

  17. As follow-up:

    I connected a jumper wire from the positive battery terminal to the hot terminal on the headlight. The voltage, with the engine running, increased from 12.9V to 13.9V and there was a noticeable increase in brightness. I would estimate about 10%. I could see a difference as I connected and disconnected the jumper wire, but I doubt if my daughter would have noticed any improvement while driving. I assume this is the most I could gain with rewiring and relays. When I connected the jumper from the negative terminal of the battery and the ground terminal on the headlight, there was no change. From that, I would conclude that the ground connections are fine.

    On the Miata forum, I found out about an upgraded bulb - Philips 9007XP Xenon +80. It is a 65/55W bulb (same wattage as stock) with an 80% higher lumen output rating. I think I will give those a try.

  18. I've been thinking about giving them a try on our 97. If you do, please share your thoughts.