when i turn on headlights they are bright then when i turn hibeams on the battery gauge drops dramaticly and the hibeams are very dim. the fuses are fine i have replaced the switch and the grounds are all hooked up. im lost please help

 

test the battery it might be time for a new one advanced auto can test it for free along with the alternator. it could be that as well hope that helps and make sure its the correct battery for your truck. when i put my high beams and auxiliary lights my volt gauge drops down

 

my truck does the same thing i have to replace the altranator and possibly battery.

 

get them tested before droping that much cash most autozone and advanced auto will test them for free while there still in the truck

 

My Explorer did this and it was my Alternator.

 

Do you have the correct bulbs in it, 9007 I believe. The 9004 look the same and will fit int the housing and connect without any problems. The difference is where the ground in the light is, the low beam work right because the ground and low hot are backwards, the High beam is dim because it has to ground through the low beam circuit.

 

My voltage gauge moves with my blinkers... But I can jack up my system, amp/sub and all, throw on the highs, and watch it not move... Mine only moves on the blinkers and when I turn the vent fan on
9004 is the proper size in my 8th gen, I'd think it's the same for a 9th if he has that

 

you might have a bad bulb or wiring problem i bet the alternator can't keep up with the sound system and may be draining the battery and charging it alot more. have you gotten the battery alternator tested yet?

 

Sealed beam up till 86, 87-91- 9004, 92-04- 9007

 

the bat is being drained and the altranator is takin a ****. i changed the bulbs to the ultra what sylvina not sure of the num but it has a blue coating on the bulb