Can a OEM 80 Series Rear Window Defroster Switch, be used to for AUX lights???????? (3 Viewers)

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I'm surprised the switch isn't just a momentary contact switch. I didn't drive my truck to work so I can't look at it. If it is auto off, it seems like it would be momentary contact because all it does is send a pulse to a timer relay that then keeps the defrost on for a pre-programmed amount of time. I don't know though because U can't look at it right now. Better look and make sure the switch pushes in and stays in or you lights will just flash once when you press the button or stay on when you hold it down.
 
The defrost switch is a regular on/off switch (no momentary action). It's another little thing I wonder about why Toyota did it this way...
 
As for the auxiliary fan, I have no idea. I read the thread a while ago and thought it was pretty neat that it could be wired up to the pressure switch, but I didn't pay much attention to the wiring. My fan clutch does a great job of keeping things cool :meh:

Maybe someone who has added the fan could chime in?
 
I was thinking of using the defrost switch for my negative trigger aux fan switch too.



I used the defrost switch to trigger my aux fan, but got a positive trigger from the defrost relay in the kick panel and just used that to control the fan relay under the hood :)

My defroster hasn't worked very well since I added limo tint years ago, so it was of no loss to me :meh:


Besides, I have cameras all around and can drive by monitor if needed ;)
 
Can someone help a wiring newbie/tard wire a pair of fogs with the 5-pin OEM rear de-frost switch? So far i was trying to figure out how to wire a relay so i found a SPST that will work and now i complicated it even more wanting to use the oem switch. What can i say? My wants are greater than my knowledge :)

So will this work:
batt--> fuse --> 30 post
light --> light --> 87 post
white/blk (off defroster) --> body gnd
yellow --> 85
jumper 30---85
fuse

Edit: not done thinking about it, will be done soon then please check..haha
 
Here you go. I gathered this from some posts and from 96r50. I wired up my fog and aux lights with the defrost switch using the following info.

Switch Wiring
Rear Defrost Switch
Slot 1, Green (12v +, for rheostat)
Slot 2, Yellow or black w/orange stripe = illumination (power)
slot 3, White w/ black stripe or blue w/ white stripe (Ground)
Slot 4, white w/ green stripe, (12v –, for rheostat)
Slot 5, not used
Slot 6, Blue w/orange or black w/ yellow stripe = Relay (power)


Dont forget about using a relay, you dont want the switch handling direct fused power without a relay.

The green with white stripe (G-W) and solid green (G) wires are for the backlighting that comes on with your taillights. They aren't shown in the diagram above. If you attach them to the same colour wires of another switch in the truck the backlighting will work properly.


The three wires (slot2,3 &6) are for the defrost circuit. The way Toyota has it set up is that the relay and the "ON" bulb both have their own power supply, and closing the switch supplies ground to both (why they did it this way I'm not sure).
If you are using the switch to control a relay you could run it the same way Toyota does,
or
you could run power in through the yellow wire (Slot 2) and attach the white with black stripe wire (Slot 3) to one of the coil pins on your relay as a positive trigger (ground the other coil pin). It depends how your lights are set up.
 
Here's a fancy picture to go along with S.CarolinaFZJ80's description.
defrost.webp
 
Let me try this:

Switch:
pin 1 + 4: splice into another pigtail with same colors
pin 2: which GND?
pin 3: which 12v+ ?
pin 6: relay 86

Relay:
30 : fuse > batt (10ga wiring)
87 : lights > light (10ga wiring and lights gnd at bumper)
85 : body gnd
86 : pin 6 on switch

Does that check out, i definitely need more electrical training :bang:
 
Keep in mind, that all you need is a 12v differential across pins 85 and 86 on the relay to connect pins 87 and 30.

So try this,

Switch
---------
pins 1,4 - splice these with the same color wires from an existing switch or dimmer switch
pin 2 - connect to vehicle ground (chassis, battery)
pin 3 - connect to +12v (battery)
pin 6 - connect to pin 85 on relay.

Relay
---------
pin 85 - connect to pin 6 on the switch
pin 86 - connect to vehicle ground (chassis, battery)
pin 87 - connect to +12v (fusing this lead wouldn't be a bad idea)
pin 30 - connect to your accessory

Thats how I have mine wired up on my breadboard at home. Seems to work for my tests.
 
This info is awsome. Any diagrams of wiring a hazard switch for lights?
 
this is great!

anyone have the patience to talk me through one of these. I am looking to use this and a rear heater switch (3 position off - low -high) to replace some non OEM switches.

using the above diagram in post #27 I want to use a lighted defroster switch to replace a contura rocker that actuated a dual battery that is normally isolated from the system. There are only two wires at present. red and orange.

using post #5 I want to use a rear heater switch to power a reverse light that can be switched off completely, made to go on with the reverse lights, or on completely. It is already wired this way with a three way contura switch and has one red lead, one black lead, and three orange leads.

I have a volt meter and will take the time to figure it out if I knew how to exactly - I appreciate your help in advance.
 
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Thanks. That sorts out what wire goes where for my fog lights & OBA switch.

I was thinking of using the defrost switch for my negative trigger aux fan switch too.

I guess I'd just have to wire the neg AC pressure switch to the defrost switch and then to the relay, in series. That way, if I leave the switch in the ON position and when ever the Auto on feature (per Sumotoy's write up)occurs, it will ground the switch and the light will come on. If I need the fan OFF,for water crossings, etc... I can just press the switch to the OFF position.

Or I could just piggy back it to the ground terminal leading to the relay and I'd be able to turn the fan ON/OFF at will but the switch light will not illuminate in the Auto on mode. Only when I select the switch ON.

Correct?

Is there any way to re-wire the defrost switch to have both?


Use a rear heater switch with a relay for aux fan

Low heat - Auto mode via AC pressure switch
High heat - Always On mode
Center - Fan Off

I use the rear defrost switch for switching just disassemble and relabel with reverse negative symbol
 
Relay

what does everyone use for relays?
 
Keep in mind, that all you need is a 12v differential across pins 85 and 86 on the relay to connect pins 87 and 30.

So try this,

Switch
---------
pins 1,4 - splice these with the same color wires from an existing switch or dimmer switch
pin 2 - connect to vehicle ground (chassis, battery)
pin 3 - connect to +12v (battery)
pin 6 - connect to pin 85 on relay.

Relay
---------
pin 85 - connect to pin 6 on the switch
pin 86 - connect to vehicle ground (chassis, battery)
pin 87 - connect to +12v (fusing this lead wouldn't be a bad idea)
pin 30 - connect to your accessory

Thats how I have mine wired up on my breadboard at home. Seems to work for my tests.

Thread revival time. Just installed this and am stuck on the part about pin 1 and 4. Are these the pins that light up the led on the switch? If so, where can I pull power for this? My switch is located next to the locker dial.
 
Thread revival time. Just installed this and am stuck on the part about pin 1 and 4. Are these the pins that light up the led on the switch? If so, where can I pull power for this? My switch is located next to the locker dial.


pin 1 is the positive feed for the switches back light - power should come from dash lights so the new switch will dim with the others pin 4 is common ground.

See post #27 for a drawing
 
So 4 and 2 can go together since the are ground?

Looking at wiring diagram I want to try and pull the power directly from the rheostat. The wiring diagram shows a solid green wire, a green and white wire, and a black and white or blue and white. According to a post in here the solid green is the 12v positive. Can anyone confirm this?
 
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Just pull the pos and neg for the back light dim from the dimmer for pin 1 & 4. This way the backlight comes on and dims the way all the other switches do.
I don't recall all the wire colors but then again they may be different depending on what vehicle the switch you are using came out of. Don't get hung up on wire colors, just use the multi meter to verify what the wires are.

Pin 3 to a solid, non-variable, ground
Pin 2 to 12v+ (I choose ACC or IGN as I didn't want the bulb to be powered if I left the switch on with the vehicle off I.e. I used the same type of power that I connected to the relay pin 87)
Pin 6 - run this to pin 85 on the relay (this completes the circuit from your switch when it's depressed and triggers the relay to allow 12v+ to go to whatever it is that you are powering).

I wired my fog lights, aux lights and rear fog this way and it works great.

Good luck

Edited- I swapped pin 2 and 3 as my memory was foggy but I looked back at the EWD pic previously in thread and refreshed my memory
 
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So 4 and 2 can go together since the are ground?

Looking at wiring diagram I want to try and pull the power directly from the rheostat. The wiring diagram shows a solid green wire, a green and white wire, and a black and white or blue and white. According to a post in here the solid green is the 12v positive. Can anyone confirm this?

Do not rely on colors, test everything
 
So there are two green wires. A solid green, and a green and white. I metered both and they both have 13 volts. I have attached a picture of the wiring for rheostat.

Also, is the black white wire the ground for the rheostat?
Rehstat.webp
Rehstat.webp
 

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