Adding Relays

[Voeltagear]

Hey everyone, I'm getting the pen and paper out to draw up a new charging and accessory wiring diagram. I have a 6 circuit fuse and relay box, plenty of 14ga and 12ga wire as well as some 8ga. I need some 4ga for the alternator to the circuit breaker. I'm planning to use relays for the voltage regulator, ignition system, headlights, 2 speed electric cooling fan, and an auxiliary 12v outlet. Do you have any other suggestions? Pictures of your component mounting, wiring? All feedback is welcome! Thank you in advance.

 

[Lightning II]

You can probably drop that relay for the ignition off of your list.

 

[Duke5A]

Electric fan is the only thing that needs relays and the headlights could benefit from them. It's a common trick that circumvents the voltage loss of having to draw the current through the headlight switch - they'll brighten up a bit. As for everything else I'm scratching scratching my head, why? Don't mess with the voltage regulator and ignition. Those circuits are fine as is. Your aux 12v outlet only needs a suitable fuse for the max draw of the outlet. Don't go relay crazy.

 

[Voeltagear]

Come to think of it, there is a relay already for the voltage regulator. The field and load relay.

 

[Mikes5thAve]

I thought it was just whatever is associated with alternator and voltage regulator. In any case I'd follow what's stock for that and not re invent anything.

 

[Aspen500]

Headlight relays work great. You can eliminate voltage drop through the dash switch and dimmer switch. Plus it takes the amp load off them also.

I went from (engine running) 11.4 volts low beam and 11.0 high beam to 12.8v at idle, hi and low beam after adding a pair of relays. At night the difference in light output is like, well, night and day. That's with Hella H4 (?) conversion headlights.
Relays in a modified Audi TT battery fuse panel. Upper right corner in the photo.

 

[Voeltagear]

Headlight relays work great. You can eliminate voltage drop through the dash switch and dimmer switch. Plus it takes the amp load off them also.

I went from (engine running) 11.4 volts low beam and 11.0 high beam to 12.8v at idle, hi and low beam after adding a pair of relays. At night the difference in light output is like, well, night and day. That's with Hella H4 (?) conversion headlights.
Relays in a modified Audi TT battery fuse panel. Upper right corner in the photo.

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That looks awesome! Also, that's the exact problem I'm trying to remedy. I'm dropping into the 11v range with headlights on.

 

[Aspen500]

It's also nice having brighter headlights because the older you get, the more light you need to see. Trust me

 

[Lightning II]

Headlight relays work great. You can eliminate voltage drop through the dash switch and dimmer switch. Plus it takes the amp load off them also.

I went from (engine running) 11.4 volts low beam and 11.0 high beam to 12.8v at idle, hi and low beam after adding a pair of relays. At night the difference in light output is like, well, night and day. That's with Hella H4 (?) conversion headlights.
Relays in a modified Audi TT battery fuse panel. Upper right corner in the photo.

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View attachment 50339

I just now recognized the that fuse & relay panel. VAG used them on the Golfs and Beetles too.