Headlamp bulb replacement - H4
Thread Starter
Racer
Joined: Jul 2004
Posts: 274
Likes: 0
From: Bergerac Dordogne
Headlamp bulb replacement - H4
Don't know if anyone can help with this. I'm trying to upgrade my H4 bulbs to 90/100s (for off road use only, of course).
The GM shop manual says open the headlight doors and reach into the space behind the headlight. As my hands are actually slightly larger than a Barbie doll's I can't get in there.
I am reaching the conclusion that the only way to change the bulb is to remove the headlight assembly to gain access.
Has anyone out there had experience of changing H4 bulbs in an export headlight, and if so, HOW DID YOU DO IT?
Thanks in advance.
The GM shop manual says open the headlight doors and reach into the space behind the headlight. As my hands are actually slightly larger than a Barbie doll's I can't get in there.
I am reaching the conclusion that the only way to change the bulb is to remove the headlight assembly to gain access.
Has anyone out there had experience of changing H4 bulbs in an export headlight, and if so, HOW DID YOU DO IT?
Thanks in advance.
Thread Starter
Racer
Joined: Jul 2004
Posts: 274
Likes: 0
From: Bergerac Dordogne
Coming in from the hood side and underneath the housing with the cowl removed meant I could reach the connectors.
That was the end of the good news, the connectors wouldn't budge so I ended up removing the headlights and having to prise the connectors off with a screwdriver - the H4 connectors are just a friction fit.
This was a mixed blessing as the rh light hood needed adjusting anyway.
Then there are the two bits of bad news at the end. The lh vertical adjuster has seized, and despite liberal dosings of plus gas and easing oil to the worm drive the torx head on the adjuster arm stripped.
Oh and there is no main beam on the lh side either.
The good news is that the dip beam is really good.
So tomorrow it's out with the pliers and the multimeter to find out what's gone wrong now . . .
Thanks for the tips guys.
H4? Just means Halogen type 4 bulb, it's the EU standard twin filament main and dip beam in one unit.
That was the end of the good news, the connectors wouldn't budge so I ended up removing the headlights and having to prise the connectors off with a screwdriver - the H4 connectors are just a friction fit.
This was a mixed blessing as the rh light hood needed adjusting anyway.
Then there are the two bits of bad news at the end. The lh vertical adjuster has seized, and despite liberal dosings of plus gas and easing oil to the worm drive the torx head on the adjuster arm stripped.
Oh and there is no main beam on the lh side either.
The good news is that the dip beam is really good.
So tomorrow it's out with the pliers and the multimeter to find out what's gone wrong now . . .
Thanks for the tips guys.
H4? Just means Halogen type 4 bulb, it's the EU standard twin filament main and dip beam in one unit.
Instructor
Joined: Feb 2000
Posts: 176
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From: Villa Ridge, Missouri
Originally Posted by Oldvetter
Don't only european headlights use H4 bulbs ?
And looking at Cochemarman's profile, he is in Europe..
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Originally Posted by Cochemarman
Don't know if anyone can help with this. I'm trying to upgrade my H4 bulbs to 90/100s (for off road use only, of course).
The GM shop manual says open the headlight doors and reach into the space behind the headlight. As my hands are actually slightly larger than a Barbie doll's I can't get in there.
I am reaching the conclusion that the only way to change the bulb is to remove the headlight assembly to gain access.
Has anyone out there had experience of changing H4 bulbs in an export headlight, and if so, HOW DID YOU DO IT?
Thanks in advance.
The GM shop manual says open the headlight doors and reach into the space behind the headlight. As my hands are actually slightly larger than a Barbie doll's I can't get in there.
I am reaching the conclusion that the only way to change the bulb is to remove the headlight assembly to gain access.
Has anyone out there had experience of changing H4 bulbs in an export headlight, and if so, HOW DID YOU DO IT?
Thanks in advance.
Pull the plug, remove the rubber boot.
The H4 has a metal clip that needs to be squeezed together and "popped" off. It's on a hinge on one side. Even when you know how it works, it still hurts your hand.
The the bulb comes out relatively easily.
Reverse the procedure to get it back in.
Here's a website that has photos of the process:
http://gstwin.com/replace_bulbs.htm
Oh, with the stock wiring, you may want to stick with 80w/80w H4s. Just a thought.
Hope this helps.
Thread Starter
Racer
Joined: Jul 2004
Posts: 274
Likes: 0
From: Bergerac Dordogne
Well, finally got the b*ggers into the car.
Still can't free the left hand vertical adjuster. The worm drive moves around about a quarter of a turn in each direction, but no more. Ah well.
"Oh, with the stock wiring, you may want to stick with 80w/80w H4s. Just a thought."
The circuits for each beam are individually fused at 10amps, giving about a 20% margin on the 100w mains and a tad more on the dips.
I've always used these bulbs with standard wiring in the past with absolutely no problems. But I'll still keep my fingers crossed!
Still can't free the left hand vertical adjuster. The worm drive moves around about a quarter of a turn in each direction, but no more. Ah well.
"Oh, with the stock wiring, you may want to stick with 80w/80w H4s. Just a thought."
The circuits for each beam are individually fused at 10amps, giving about a 20% margin on the 100w mains and a tad more on the dips.
I've always used these bulbs with standard wiring in the past with absolutely no problems. But I'll still keep my fingers crossed!
