High beam - low beam

[AtlantaRick]

2005 Ambassador 36PRT. When I turn on the high beam headlights the low beams go off. Is that normal? Shouldn't all 4 bulbs come on when the high beams are on?

[DtBt]

Most work as you have observed using typically 9006 low beam bulbs and 9005 for high beam. Some Sigs and perhaps others use 9003/HB4 low beam bulbs that have two elements, one for low beam and one for high beam.

[wa8yxm]

There are several systems, 2 lamp systems the high beams and low beams are the same lamps.. Different elements only one is on at a time

4: Lamp systems sometimes the outside lamps work just like the 2 lamp, Sometimes they are.. usually HIGH beams only

And the inside pair is LOW beam only

In all cases the LOW beams are shut off when the high beams are on

Electricaly the beam switch is SPDT (Single pole double throw) it feeds one or the other but not both.

[AtlantaRick]

Thanks. I have the 4 bulb version so I guess mine is working as designed since the low beams turn off when the high beams are on. Thanks again

[mel s]

Originally Posted by AtlantaRick

2005 Ambassador 36PRT. When I turn on the high beam headlights the low beams go off. Is that normal? Shouldn't all 4 bulbs come on when the high beams are on?

AtlantaRick
I believe that's normal.....it is on my coach, (and has been on every other vehical I've owned).

BTW, on my '07 Saturn ION toad if the driving lights in the grill are ON while the low beams are ON, if/when the headlights are switched from "low" to "high"... not only the low beams go off.... (the driving lights also "go OFF").

Mel
'96 Safari Sahara

[TonyMac]

Well, if you don't like it, change it. JCWhitney offers a relay that keeps all four headlights on when you go to High beam, and it does make a difference. Low beams are low and flat, high beams are straighter and narrower. I like having both when I can use the high beams. Power for the lows comes thru the new relay when the highs are on, so it won't overload your vehicle's headlight relay. Very simple installation, less than a six pack. Got it on two of my vehicles that have four lamp systems.