WJBertrand

This question is for Mustangs having the factory HIDs fitted only. Please don't answer if you have non-HID halogen headlights or aftermarket HIDs:


What do your HIDs do when you pull the multifunction lever rearward, toward the steering wheel when the headlights are off?


On my car the HIDs flash for a split second but do not stay on, even if I am holding the lever. Shouldn't they stay on until I release the lever?

If the head lights are already on, pulling the multifunction lever rearward turns on the high beams and they stay on until I release the lever as expected, and the way they work in every other car I've owned.

What does yours do?

jz78817

2012,factory HIDs. Pull the lever back, the low-beam shutters drop and the headlamps flash briefly.

because the HID arc is already struck. a common misconception is that high-beams are brighter than low-beams (people used to call hi-beams the "brights.") they aren't, they're just aimed higher. Halogens do this by having the hi-beam filament right in the focal point of the reflector, and the low-beam filament offset a bit upward (to project light downward a bit.)

with HIDs, the electrodes erode every time you strike an arc and sustain it. So when you "flash to pass" with the headlamps off, all you want is a brief flash. Your headlamps are working as designed.

Cruzinaround

^^^^what he says....They "flash" on briefly then they're off. Just checked mine.

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WJBertrand

Thanks guys. To jz, yeah, I am aware that the same arc is used for both high and low beams in the Mustang's design, with a movable reflector / shutter to redirect the beam. I have a set of aftermarket HIDs on my motorcycle that work similarly. The last car I had (Lexus IS300) actually used the HIDs only for the low beams with the high's remaining as halogens.

BTW, with respect to halogen bulb design most H/L bulbs (e.g. H4) are 55w low/60w high so the "brights" are in fact slightly brighter as well as being aimed higher. If you look closely at a halogen bulb, you'll see there's a shield under the low beam filament. This directs the light toward the upper part of the reflector, which then reflects it more downward. The high beam filament is unshielded so uses both the upper and lower parts of the reflector.

This the first car I've owned with factory HIDs using the same lamp for both low and high beams. I wonder of other cars that use the same HIDs for both beams behave similarly?

Your responses confirm that this is normal behavior, but the flash is so brief as to be practically useless IMNSHO. You would miss it if you blink!

Cruzinaround

I usually flick a series of three to four times when signalling drivers coming the other way that a deer is ahead or a cop... I don't recall ever having flicked the brights just once????

I just kinda do it automatically. But it would be kinda nice if Ford implemented some kind of capacitor that would discharge a sequence of three or four flashes off the HID's.

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jz78817

Ford vehicles are the only ones I've encountered which have you pull the stalk one way for flash-to-pass and push it the other way for hi beams. in all other brands I've driven, you pull the stalk partway to flash (and release it,) and for hi beams you pull all the way back past a detent where they stay on.

WJBertrand

Toyota and Lexus vehicles (which is mostly what we've owned) work this way, back and hold for flash-to-pass (headlights already on or not) and click the stalk forward to keep the high beams on (if the headlights are already on). So the Mustang's system works the same as Toyota/Lexus/Scion except that the flash-to-pass beams do not stay on when holding the lever back when the headlights are off.

Cruzinaround

Unless things have changed in the later models...it is the same on my 2000 Durango and my 2004 SRT4. The Beemer is the same also ...I'll confirm with the wife...

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jz78817

nope, I had an SRT-4 and it was like most other Chryslers. Pull back on the stalk slightly and release to flash, pull back fully to turn on the hi-beams.

Cruzinaround

Now I'm not sure.... I'll have to go in the shed tonight and check... But, I remember pull back to flash. Push forward to stay on.

Maybe I've been in the Ford too long?

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