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SKL1
Putting in the 100W hi beam H4's and need the wiring diagram to install the relay(s) so the 40 year old wiring system can handle it.
Can't find it anywhere and search wasn't helpful...

TIA.
VaccaRabite
Get relays from FLAPS and the diagram is on the box. Makes it really easy.
If you are running big lights like that I'd make the power run all the way back to the battery (remember to keep it fused).
Mike Bellis
Read this...

Click to view attachment
SirAndy
QUOTE(Vacca Rabite @ May 12 2013, 06:32 PM) *
If you are running big lights like that I'd make the power run all the way back to the battery (remember to keep it fused).

agree.gif

I'm not sure the stock wires can handle the 100W in the long run.
idea.gif
Cap'n Krusty
QUOTE(SirAndy @ May 12 2013, 08:41 PM) *

QUOTE(Vacca Rabite @ May 12 2013, 06:32 PM) *
If you are running big lights like that I'd make the power run all the way back to the battery (remember to keep it fused).

agree.gif

I'm not sure the stock wires can handle the 100W in the long run.
idea.gif


That's why you run relays. Big wires from the battery to the relays, big wire from the relays to the bulbs, big ground wires. The stock wiring is used to activate the relays. We do this all the time in Audis in order to save the combi switches, even with stock bulbs.

The Cap'n
SirAndy
QUOTE(Cap'n Krusty @ May 12 2013, 09:33 PM) *
QUOTE(SirAndy @ May 12 2013, 08:41 PM) *
QUOTE(Vacca Rabite @ May 12 2013, 06:32 PM) *
If you are running big lights like that I'd make the power run all the way back to the battery (remember to keep it fused).

agree.gif

I'm not sure the stock wires can handle the 100W in the long run.
idea.gif


That's why you run relays. Big wires from the battery to the relays, big wire from the relays to the bulbs, big ground wires. The stock wiring is used to activate the relays. We do this all the time in Audis in order to save the combi switches, even with stock bulbs.

The Cap'n

I know. That's why i agreed with Zach's post who basically said the same thing ...
biggrin.gif
SKL1
I may be an idiot, but what is FLAPS?? I see it all the time and don't know what it stands for...
Rleog
QUOTE(SKL1 @ May 13 2013, 07:47 AM) *

I may be an idiot, but what is FLAPS?? I see it all the time and don't know what it stands for...



Friendly Local Auto Parts Store, or, many other more creative versions.
jim_hoyland
What size wires should be used:

Battery to relay
Relay to light(s)
Min Amperage of relay
0396
QUOTE(kg6dxn @ May 12 2013, 08:32 PM) *




thank you piratenanner.gif
orthobiz
I don't see wire gauge size in the "Relay Book" linked in one of the responses.

Paul
r_towle
Volts * Amps = Watts
12 V * ?Amps = 100 Watts
OR
? Amps =100W/12V
OR
8.33 Amps = 100W/12V
Use a 10Amp fuse inline and you can get by with 16Ga wire.

Read the AMP draw on the device you will be using.
It will be on the package somewhere.

rich
r_towle
Oh,

Only use the stock wiring for the trigger on the relay.
The stock light switch is already over stressed, it will melt, and they are NLA anywhere.

ITs a pain, but run new wires up through the tunnel, into the interior, up over the steering column (zipties) and through the main grommet into the front trunk to power those lights.

Rich
orthobiz
Thanks.

Paul
jim_hoyland
Will one relay power low beams and high beams ? Or, are two relays needed ?
Mike Bellis
QUOTE(jim_hoyland @ Sep 3 2013, 06:01 PM) *

Will one relay power low beams and high beams ? Or, are two relays needed ?

2 relays required
r_towle
It's two different circuits, so two relays are required.

One larger wire for dedicated power to a common jumpered pole to supply power for both is ok, you don't use both circuits at the same time.

Rich
JeffBowlsby
Here is the wiring diagram for the high/low beams + ground headlight circuits.

As a place to start for design purposes, consider the factory main power wire off the headlight switch to the fuses as 14 AWG, from the fuses to each headlight and ground wires are 16 AWG. As I recall the wiring is not as much of an issue as the ehadlight switch in terms of ampacity. Hopefully someone will figure out the new circuitry configuration and relay configuration, wire gages required for specific lamp sizes, and post it.

The headlights are L1/L2.
jim_hoyland
See: http://www.rowand.net/Shop/Tech/WiringHeadlightRelays.htm

Most of your questions are answered plus there is a neat wiring diagram. smile.gif
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