kevinbo03
Rollin' OEM style
This is a guide to the inner workings of the OEM Foglight switch.
This may be useful if you are having trouble making a Civic foglight kit work with your OEM switch, or if you wish to use the switch for another purpose and want to know how to connect your devices without wasting time troubleshooting and blowing out bulbs. This guide also has information on the two bulbs in the OEM foglight switch.
This is a picture showing the purpose of the pins on the back of the switch. As I have attempted to convey by drawing the lower "step" on the switch, this drawing show the switch sitting upright with the on/off indication light sitting at the TOP:
Backup link
Switch's electrical diagram:
Backup link
Details:
Purpose:
Switch is designed to toggle on/off a 12v signal. 12v signal can be
used to toggle a relay, or power a LOW amperage device (NOT foglights. USE A
RELAY)
Pin descriptions:
(Listed from top to bottom based of perspective in picture above)
-Pin 1: Ground #1. This is the ground for the on/off indication light
(the green light that turns on when the switch is depressed to the ON
position). It is acceptable for this pin to share a source with pin #5.
-Pin 2: This is the 12v signal wire intended to connect to the fog
light system's relay. This is what the switch toggles on and off. When live,
this pin also provides power to the on/off indication light.
-Pin 3: 12v power input #1. This is the source of power for the on/off
indication light, and the 12v output that is activated when the switch is
depressed to the ON position. Power may be obtained from any source, or the
same source as pin #4 for simplicity
-Pin 4: 12v power input #2. This is the source of power for the backlit
illumination of the foglight symbol. This 12v should be sourced from a 12v
power source that is only activated when the car's lights are NOT in the off
position. Examples include the moonroof or cruise control switch. Use a
multimeter to source a 12 wire from either of these switched that is ONLY live
when the lights are turned on. You *can* use any source if you wish, but the
foglight symbol will then always remain backlit, even with the lights off.
Acceptable for some, unacceptable for OCD folks such as myself. Just do it
right!
-Pin 5: Ground #2. This is the ground for the backlight. It is
acceptable for this pin to share a source with pin #1.
Bulbs:
The two bulbs in the foglight switch are the same size and type used in the digital clock. Pic:
Both bulbs in the foglight switch are T3 Neo Wedge bulbs (8mm). The on/off indication bulb has a blue rubber shielding, the backlight bulb does not. OEM replacements are available from your local dealership and online for $2-$5 EACH. If anyone knows the part numbers please share, I know similar bulbs are found in the heater panel and the digital clock.
LED replacements are available in different colors at many places, here is one source:
http://autolumination.com/74.htm
Scroll down or press Ctrl+F to find product titled:
"Japanese OEM Neo - Wedge LED Instrument Panel Bulbs Type A, B & C"
The 3 products after the first Neo-Wedge bulb are all compatible as long as you order T3 size (Type A).
Recommendations:
-Source your 12v from the moonroof or foglight switch. This way, the switch will only allow foglights to turn on if the headlight switch is NOT in the "off" postion. Also, it will make the foglight switch illuminate only when other interior lights are illuminated.
-Using this information, the foglight switch may be used to toggle any relay for any purpose. Examples may include an air compressor, air horns, interior footwell lighting, etc.
-Use this guide if you eBay Civic Foglight kit does not have the same color coding as described in Russianred's guide. Only one wire must pass through the firewall, that is the 12v signal wire connected to the kit's relay. All other pins can be sourced within a few feet of the switch.
-You may find it easier to solder the connections to your switch. I used female D-sub connector pins as recommended by Russianred in his guide, but decided to solder these pins on to prevent them from coming loose. Adding extra slack on all 5 wires and putting a quick-disconnect between them allows the switch to still be easy to remove, but prevent loose connections.
My Experience:
I had installed an 01-03 Civic foglight kit, and used the included switch for awhile. I eventually bought an OEM switch, but the colors and quantities of wires on my foglight switch harness didn't match up to anyone else's. All I needed was a detailed pinout of what each pin on the switch does, so I could make it work. I could not find one, so I spent a few hours taking it apart and working out the best solution. The switch is hard to disassemble without breaking, and I decided it would be nice of me to share my experience with others who may find them self in a similar predicament.
I hope you found this information useful, please post if you have any comments or suggestions that others may find helpful, or that you found helpful in your own installations.
Cheers,
-Kevin B
This may be useful if you are having trouble making a Civic foglight kit work with your OEM switch, or if you wish to use the switch for another purpose and want to know how to connect your devices without wasting time troubleshooting and blowing out bulbs. This guide also has information on the two bulbs in the OEM foglight switch.
This is a picture showing the purpose of the pins on the back of the switch. As I have attempted to convey by drawing the lower "step" on the switch, this drawing show the switch sitting upright with the on/off indication light sitting at the TOP:
Backup link
Switch's electrical diagram:
Backup link
Details:
Purpose:
Switch is designed to toggle on/off a 12v signal. 12v signal can be
used to toggle a relay, or power a LOW amperage device (NOT foglights. USE A
RELAY)
Pin descriptions:
(Listed from top to bottom based of perspective in picture above)
-Pin 1: Ground #1. This is the ground for the on/off indication light
(the green light that turns on when the switch is depressed to the ON
position). It is acceptable for this pin to share a source with pin #5.
-Pin 2: This is the 12v signal wire intended to connect to the fog
light system's relay. This is what the switch toggles on and off. When live,
this pin also provides power to the on/off indication light.
-Pin 3: 12v power input #1. This is the source of power for the on/off
indication light, and the 12v output that is activated when the switch is
depressed to the ON position. Power may be obtained from any source, or the
same source as pin #4 for simplicity
-Pin 4: 12v power input #2. This is the source of power for the backlit
illumination of the foglight symbol. This 12v should be sourced from a 12v
power source that is only activated when the car's lights are NOT in the off
position. Examples include the moonroof or cruise control switch. Use a
multimeter to source a 12 wire from either of these switched that is ONLY live
when the lights are turned on. You *can* use any source if you wish, but the
foglight symbol will then always remain backlit, even with the lights off.
Acceptable for some, unacceptable for OCD folks such as myself. Just do it
right!
-Pin 5: Ground #2. This is the ground for the backlight. It is
acceptable for this pin to share a source with pin #1.
Bulbs:
The two bulbs in the foglight switch are the same size and type used in the digital clock. Pic:
Both bulbs in the foglight switch are T3 Neo Wedge bulbs (8mm). The on/off indication bulb has a blue rubber shielding, the backlight bulb does not. OEM replacements are available from your local dealership and online for $2-$5 EACH. If anyone knows the part numbers please share, I know similar bulbs are found in the heater panel and the digital clock.
LED replacements are available in different colors at many places, here is one source:
http://autolumination.com/74.htm
Scroll down or press Ctrl+F to find product titled:
"Japanese OEM Neo - Wedge LED Instrument Panel Bulbs Type A, B & C"
The 3 products after the first Neo-Wedge bulb are all compatible as long as you order T3 size (Type A).
Recommendations:
-Source your 12v from the moonroof or foglight switch. This way, the switch will only allow foglights to turn on if the headlight switch is NOT in the "off" postion. Also, it will make the foglight switch illuminate only when other interior lights are illuminated.
-Using this information, the foglight switch may be used to toggle any relay for any purpose. Examples may include an air compressor, air horns, interior footwell lighting, etc.
-Use this guide if you eBay Civic Foglight kit does not have the same color coding as described in Russianred's guide. Only one wire must pass through the firewall, that is the 12v signal wire connected to the kit's relay. All other pins can be sourced within a few feet of the switch.
-You may find it easier to solder the connections to your switch. I used female D-sub connector pins as recommended by Russianred in his guide, but decided to solder these pins on to prevent them from coming loose. Adding extra slack on all 5 wires and putting a quick-disconnect between them allows the switch to still be easy to remove, but prevent loose connections.
My Experience:
I had installed an 01-03 Civic foglight kit, and used the included switch for awhile. I eventually bought an OEM switch, but the colors and quantities of wires on my foglight switch harness didn't match up to anyone else's. All I needed was a detailed pinout of what each pin on the switch does, so I could make it work. I could not find one, so I spent a few hours taking it apart and working out the best solution. The switch is hard to disassemble without breaking, and I decided it would be nice of me to share my experience with others who may find them self in a similar predicament.
I hope you found this information useful, please post if you have any comments or suggestions that others may find helpful, or that you found helpful in your own installations.
Cheers,
-Kevin B
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