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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: belfert on September 23, 2011, 07:49:50 AM

Title: Can anyone verify the wiring for an H4 headlight bulb? (See photo)
Post by: belfert on September 23, 2011, 07:49:50 AM

I am trying to verify that I have my H4 headlight bulbs properly wired.  Does the attached photo have the blades properly labeled?

I don't think I wired things right the first time and I want to verify before I fix things.

Title: Re: Can anyone verify the wiring for an H4 headlight bulb? (See photo)
Post by: Van on September 23, 2011, 08:09:43 AM

That looks correct Brian. GL

Title: Re: Can anyone verify the wiring for an H4 headlight bulb? (See photo)
Post by: belfert on September 23, 2011, 09:43:06 AM

Thanks for the verification!

It appears I reversed the high beam and ground which causes the low beams to be weak, but the high beams will work fine.  This is apparently a common issue when people plug H4 bulbs into a normal socket.  I put in new sockets so I must have misread a wiring diagram somewhere as I knew H4 is different.

Title: Re: Can anyone verify the wiring for an H4 headlight bulb? (See photo)
Post by: belfert on September 23, 2011, 06:39:29 PM

I spent close to three hours taking apart my headlight system this evening and verifying each of the wires.  I found that one of the low beams had the high beam and ground reversed.

The one low beam was only getting 13 volts instead of the proper 26 volts because of the wires being reversed.  The headlights should work better now after I get them aligned again on Monday.