mlb585

I'm trying to find out which pins on the back of the fog light switch controls what. I don't have the stock harness so the specific wire color won't help. Does anyone know which pins are ground, power, signal, etc.? Any help on this would be greatly appreciated. Thanks

1fasttl

All you need is a test light to find out which one is power and there is another that has power all the time. Are you trying to do the mod on the fog's?

mlb585

I am just trying to retrofit this in my 2003 CLS. I just need to know which pins do what when wiring this up. Does anyone have a diagram of what pins go to which wires?

benzo555

OK I wired this up last year to fit to my PIAA kit. As you can see PIAA uses only 3 wires (right) and OEM switch (Left) I did not want to use the PIAA switch, so I wired up for the OEM switch.

OEM pins
Black/brown (-)ground
Red/silver (-) another ground ground from headlights I believe

Blue/Brown (+) +Signal for headlights I believe
Red/Black (+) +12V

Green Brown (+) Signal

PIAA pins
Red (+) 12V
Black (-) GRound
White(+) Signal

I hope this will give you an idea. btw this is an accord fog switch. Not sure if the pin color is the same as the TL or CL.

hzm82

Hey you're in Gainesville FL just like me!

If you hold the Fog light switch the correct way, the top should be where the green light is.


So going from the top most pin.

First pin is Ground side for indicator light (White wire/blue line wires on harness)

Second pin is to relay switch (Blue/Red)

Third pin is for power from the headlight source(White/Red)

4th pin is for power from tailight source (Red/Black) [This power up the background light for the switch, needs the 5th pin to be grounded to work]

5th is for connection to dash dimmer relay (Red) [Allows you to dim the switch light or you can just ground it so the background light on the switch works, however just grounding it will make the background light stay at max light output]


If you need help or want to hang out, give me an email at hzm82@yahoo.com