Electrical help from the Guru's

I just finished up the relay upgrade on the car and cant beleive how well I can actually see at night but I need some help on my driving lights now. What I would like to have is them also on a relay coming on when I flip their toggle switch but also anytime I have the headlights on low or high...I dont understand electrical flow and would think that they being powered would keep all 3 relays on at all times and I would have no high and low beams....I'm sure theres an electrical "widget" that would allow this to happen....Right?
 
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Here is a simple drawing of how to connect the relay for the DRIVING lights.

Come off the key for power to the under dash switch so that the lights will turn off with the key and not drain your battery if left on by accident.
BE SURE TO PUT A FUSE ON THE POWER TO THE RELAY FROM THE BATTERY!!!
The terminal numbers are on the bottom of the relay.
The relays can be bought at radioshack or online.

We order the relays and sockets from:
Audio and Video, Computer Parts, Batteries, Cable and Wiring at MCM Electronics

40A Automotive 12V Relay | Multicomp | CMA31-DC12V-A
40A Automotive 12V Relay
cost $1.04 each

RELAY SOCKET 5-PIN FOR BOSCH TYPE AUTO RELAY | MCM Audio Select | 26-1942
RELAY SOCKET 5-PIN FOR BOSCH TYPE AUTO RELAY
cost $1.29 each
 

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Shakin66
Electrical help from the Guru's

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I just finished up the relay upgrade on the car and cant beleive how well I can actually see at night but I need some help on my driving lights now. What I would like to have is them also on a relay coming on when I flip their toggle switch but also anytime I have the headlights on low or high...I dont understand electrical flow and would think that they being powered would keep all 3 relays on at all times and I would have no high and low beams....I'm sure theres an electrical "widget" that would allow this to happen....Right?

The "widget" you need is a diode. Actually two. It acts as an electrical check valve only allowing current to flow one way. Here's a schematic diagram to help you wire them up:

HeadlampRelays.jpg


edit: You could get away with just one diode, but you would have to run another wire from the dimmer switch. This allows you to wire up the driving light relay close to the other headlamp relays.

Make sure you hook them up correctly. The Cathode is the line side of the diode and the Anode is the triangle side. There will be a line on the diode indicating the cathode end.
 

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I should probably mention that some places have laws that require Fog Lamps to turn off with the high beams and Driving lights turn off with the low beams. So if you live in an area where the local law enforcement are not friendly, this wiring method doesn't give you the option to turn them off with the lights on.

As long as the aux lights are aimed right (not too high) it shouldn't attract attention.
 
I should probably mention that some places have laws that require Fog Lamps to turn off with the high beams and Driving lights turn off with the low beams. So if you live in an area where the local law enforcement are not friendly, this wiring method doesn't give you the option to turn them off with the lights on.

As long as the aux lights are aimed right (not too high) it shouldn't attract attention.

I missed the part where Shakin66 wanted the fog lights to come on with the headlights at all times. Good job