Need help Choosing a relay
Thread Starter
Melting Slicks
Joined: Dec 2006
Posts: 2,367
Likes: 0
From: East Oakland CA
Need help Choosing a relay
i need help choosing the correct relay to keep my Fog lights on when i flash my high beams. i could just order a harness from radio flyer but i like building my own things when i can.
main problem is I've seen 2 designs. one has 4 wires and the other has 5? the only thing they have in common are the numbers 30,85,86,87 and 87a(for the 5th wire?) which mean nothing to me lol was hoping somebody could help me out
TIA
BTW i have ACA lights so I'm already able to keep both my high and low beams on
main problem is I've seen 2 designs. one has 4 wires and the other has 5? the only thing they have in common are the numbers 30,85,86,87 and 87a(for the 5th wire?) which mean nothing to me lol was hoping somebody could help me out
TIA
BTW i have ACA lights so I'm already able to keep both my high and low beams on
Last edited by mickey_7106; Dec 2, 2013 at 05:18 PM.
Melting Slicks
Joined: Sep 2011
Posts: 2,258
Likes: 543
From: Appleton WI
FYI - Most states only allow 4 white lights to be on at the same time. If you drive with your lows, highs, and fogs on, you could get a ticket. I know your intention is for flash to pass but don't know how much high beam driving you do.
What is the reason for keeping the fogs on when you flash? Are they HID and need time to fire up again?
What is the reason for keeping the fogs on when you flash? Are they HID and need time to fire up again?
Burning Brakes
Joined: Oct 2013
Posts: 859
Likes: 1
Non corvette-related, but when I wired off road lights on my truck, I only used a 4 prong relay. Here is the schematic for the relay that I used when wiring my lights:
87 is to lights (accessory)
30 is to battery or power source
86 is to switch
85 is to ground
Furthermore, to find the correct amperage of the relay you will need, you take the wattage of the lights and divide by 12 volts. so, if the lights were say 55 watts each, it would be 110/12= 9.16 amp relay (10 amp relay). Hope this makes sense!!
This is the site I used with the same info that I have explained to you: http://www.therangerstation.com/tech...ry/relays.html
87 is to lights (accessory)
30 is to battery or power source
86 is to switch
85 is to ground
Furthermore, to find the correct amperage of the relay you will need, you take the wattage of the lights and divide by 12 volts. so, if the lights were say 55 watts each, it would be 110/12= 9.16 amp relay (10 amp relay). Hope this makes sense!!
This is the site I used with the same info that I have explained to you: http://www.therangerstation.com/tech...ry/relays.html
Drifting
Joined: Oct 2011
Posts: 1,872
Likes: 333
From: Olmsted Falls Ohio
St. Jude Donor '12 thru '24
What you are working with in the picture is the Bosch automotive relay. Take a look at the following for the basics and scroll down to where they talk about the Bosch unit.
http://www.bcae1.com/relays.htm
http://www.bcae1.com/relays.htm
Thread Starter
Melting Slicks
Joined: Dec 2006
Posts: 2,367
Likes: 0
From: East Oakland CA
FYI - Most states only allow 4 white lights to be on at the same time. If you drive with your lows, highs, and fogs on, you could get a ticket. I know your intention is for flash to pass but don't know how much high beam driving you do.
What is the reason for keeping the fogs on when you flash? Are they HID and need time to fire up again?
What is the reason for keeping the fogs on when you flash? Are they HID and need time to fire up again?
Non corvette-related, but when I wired off road lights on my truck, I only used a 4 prong relay. Here is the schematic for the relay that I used when wiring my lights:
Attachment 47750415
87 is to lights (accessory)
30 is to battery or power source
86 is to switch
85 is to ground
Furthermore, to find the correct amperage of the relay you will need, you take the wattage of the lights and divide by 12 volts. so, if the lights were say 55 watts each, it would be 110/12= 9.16 amp relay (10 amp relay). Hope this makes sense!!
This is the site I used with the same info that I have explained to you: http://www.therangerstation.com/tech...ry/relays.html
Attachment 47750415
87 is to lights (accessory)
30 is to battery or power source
86 is to switch
85 is to ground
Furthermore, to find the correct amperage of the relay you will need, you take the wattage of the lights and divide by 12 volts. so, if the lights were say 55 watts each, it would be 110/12= 9.16 amp relay (10 amp relay). Hope this makes sense!!
This is the site I used with the same info that I have explained to you: http://www.therangerstation.com/tech...ry/relays.html
What you are working with in the picture is the Bosch automotive relay. Take a look at the following for the basics and scroll down to where they talk about the Bosch unit.
http://www.bcae1.com/relays.htm
http://www.bcae1.com/relays.htm
http://www.frys.com/product/4191633?...H:MAIN_RSLT_PG
Drifting
Joined: Mar 2011
Posts: 1,412
Likes: 15
From: Richardson TX
Either relay will work.
The 5 pin relays are DOUBLE THROW relays.
the 5th pin is the "normally closed" pin.
As you can see in the diagrams, the extra pin on the 5 pin relay is connected to the common pin when the coil is not energized.
You don't need the 5th pin for your purpose, but it doesn't hurt to have it, it will function in the same exact way as the 4 pin relay. Most standard relays you buy for automotive purposes have the 5th pin, usually labeled 87a.
tl;dr it will work
The 5 pin relays are DOUBLE THROW relays.
the 5th pin is the "normally closed" pin.
As you can see in the diagrams, the extra pin on the 5 pin relay is connected to the common pin when the coil is not energized.
You don't need the 5th pin for your purpose, but it doesn't hurt to have it, it will function in the same exact way as the 4 pin relay. Most standard relays you buy for automotive purposes have the 5th pin, usually labeled 87a.
tl;dr it will work
Thread Starter
Melting Slicks
Joined: Dec 2006
Posts: 2,367
Likes: 0
From: East Oakland CA
awesome. if i get the 5 pin relay 87a won't have to connected to anything since its spring loaded right?
Either relay will work.
The 5 pin relays are DOUBLE THROW relays.
the 5th pin is the "normally closed" pin.
As you can see in the diagrams, the extra pin on the 5 pin relay is connected to the common pin when the coil is not energized.
You don't need the 5th pin for your purpose, but it doesn't hurt to have it, it will function in the same exact way as the 4 pin relay. Most standard relays you buy for automotive purposes have the 5th pin, usually labeled 87a.
tl;dr it will work
The 5 pin relays are DOUBLE THROW relays.
the 5th pin is the "normally closed" pin.
As you can see in the diagrams, the extra pin on the 5 pin relay is connected to the common pin when the coil is not energized.
You don't need the 5th pin for your purpose, but it doesn't hurt to have it, it will function in the same exact way as the 4 pin relay. Most standard relays you buy for automotive purposes have the 5th pin, usually labeled 87a.
tl;dr it will work
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Drifting
Joined: Mar 2011
Posts: 1,412
Likes: 15
From: Richardson TX
Thread Starter
Melting Slicks
Joined: Dec 2006
Posts: 2,367
Likes: 0
From: East Oakland CA
update.
I'm almost done with this but have one quick question. after a quick search i noticed that a few people used a 12 gauge power line. i used 18 gauge for all 4 wires. will the 18 gauge hurt "performance", that or melt the wire??
I'm almost done with this but have one quick question. after a quick search i noticed that a few people used a 12 gauge power line. i used 18 gauge for all 4 wires. will the 18 gauge hurt "performance", that or melt the wire??
Le Mans Master
Joined: Mar 2011
Posts: 6,835
Likes: 302
From: Columbia SC
Thread Starter
Melting Slicks
Joined: Dec 2006
Posts: 2,367
Likes: 0
From: East Oakland CA
i got it all hooked up but its not working like i want it too. Fog lights flicker when the high beams go off. any ideas?
i had pin
30 to power
85 to ground behind battery
86 to F12
87 to F6
BTW don't mind the ****** looking paint or plate lol
thanks
i had pin
30 to power
85 to ground behind battery
86 to F12
87 to F6
BTW don't mind the ****** looking paint or plate lol