So, I decided to add an LED to my GTI to tell me when the mirror defroster is turned on.
Mirror defroster off:
Mirror defroster on:
How-To:
Remove the door trim. There are other how-tos on here for that, so I'll skip over that. Here's the back of the interior door trim. Unclip the window and mirror controls by disengaging the 4 clips holding it in place. You'll need a screw driver to get to the bottom clip. Push the control module toward the front side of the door trim.
Here it is, freed from the door trim.
Remove the mirror control section. There are three clips. Gently pry them loose. Next, drill a hole for your LED. I chose a 3mm LED, which fits nicely in the corner indicated below. A 1/8" bit works well. Drill from the backside of the control module.
Here's the hole from the front.
Okay, let's shift gears. We need a 3mm LED and a resistor. I used a yellow LED and a 560 Ohm resistor. The LED is pretty bright, so I might swap out the resistor for a larger value to dim it down a bit. Sanding the surface of the LED might take a little of the brightness out of it, too.
Update: A resistor value around 10kOhm is about right for a more pleasant brightness.
Here's the setup.
Use some heat shrink to tidy things up.
Let's figure out how to mount this now. I drilled two additional holes for a zip tie.
Make sure to orient your zip tie so that the mirror control will fit back into place.
I ended up using some wiring harness tape to make a decent looking harness.
Now, we'll wire this up to the mirror defrost circuit. The wires are in the harness here.
Expose the individual wires. Be careful not to cut the wires. Isolate the red/black and blue/black wires. These power the the driver's side mirror defroster.
Snap the window and mirror controls back into the door trim before proceeding, or you'll be sad.
Grab a pair of wire taps like these.
Make the connections:
LED positive to Red/Black.
LED negative to Blue/Black.
Tape up the wires and put the door back together.
And we're done!
Mirror defroster off:
Mirror defroster on:
How-To:
Remove the door trim. There are other how-tos on here for that, so I'll skip over that. Here's the back of the interior door trim. Unclip the window and mirror controls by disengaging the 4 clips holding it in place. You'll need a screw driver to get to the bottom clip. Push the control module toward the front side of the door trim.
Here it is, freed from the door trim.
Remove the mirror control section. There are three clips. Gently pry them loose. Next, drill a hole for your LED. I chose a 3mm LED, which fits nicely in the corner indicated below. A 1/8" bit works well. Drill from the backside of the control module.
Here's the hole from the front.
Okay, let's shift gears. We need a 3mm LED and a resistor. I used a yellow LED and a 560 Ohm resistor. The LED is pretty bright, so I might swap out the resistor for a larger value to dim it down a bit. Sanding the surface of the LED might take a little of the brightness out of it, too.
Update: A resistor value around 10kOhm is about right for a more pleasant brightness.
Here's the setup.
Use some heat shrink to tidy things up.
Let's figure out how to mount this now. I drilled two additional holes for a zip tie.
Make sure to orient your zip tie so that the mirror control will fit back into place.
I ended up using some wiring harness tape to make a decent looking harness.
Now, we'll wire this up to the mirror defrost circuit. The wires are in the harness here.
Expose the individual wires. Be careful not to cut the wires. Isolate the red/black and blue/black wires. These power the the driver's side mirror defroster.
Snap the window and mirror controls back into the door trim before proceeding, or you'll be sad.
Grab a pair of wire taps like these.
Make the connections:
LED positive to Red/Black.
LED negative to Blue/Black.
Tape up the wires and put the door back together.
And we're done!
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