2012 Fog relay

[CTScott]

Originally Posted by Absolutely Red 12

No DRLs.

Also now using a PIAA switch, as the cheap Chinese Toyota looking switch would not allow the fogs to turn off.

New switch is a 3 wire, internal lighting, when on. It also allows the dash icon to turn on!!

You should use a four, not three wire switch. The illumination should be isolated from the switching.

I just noticed that for both the DRL and non-DRL Yaris the fog relay coil is tied directly to the body ECU internally in such a way that it prevents the fogs from turning on except when it decides it is OK to. You would have to either do some surgery on the body ECU or use an external relay and rewire the fogs to it to override that behavior.