Blue LED Switch Replacement (Anytime Backup Camera)

I was hesitant to purchase the Anytime Backup Camera (ABC) because the color blue on the switch does not match the Toyota blue color on the OEM switches. The ABC switch LED is too bright and too blue. To my knowledge, Air on Board (AOB) is the only switch provider that matches the Toyota OEM blue. Unfortunately AOB does not offer a Toyota blue single pole, dual-throw switch.

Ultimately I purchased the Anytime Backup Camera and decided to alter the switch to more closely match the OEM blue.

Here's what I did:
I happened to have an Air On Board (AOB) switch with the OEM blue color on hand that I didn't need anymore so I disassembled both the ABC and the AOB switch. If you don't have a spare AOB switch laying around, you can still improve the ABC switch with just a resistor add/change. Keep reading.

The ABC switch. I labeled the direction of the switch plate so when I reassembled I'd have the front and rear camera labeled correctly:






The current limiting resistor for the illumination LED is the center resistor in the triplet. The circuit for the ABC illumination LED is very simple as shown below,


The resistor sets the current in the LED which translates to how bright the LED shines. With your dash illumination turned to its brightest setting, the illumination voltage is 12V. Most LEDs have a voltage drop of ~0.7V so the ABC circuit has a current of (12V-0.7V) / 4700 = 2.4mA.

The AOB switch. Again start by disassembling and mapping the circuit.


The circuit for the AOB illumination LED is also very simple as shown below,

By the same circuit analysis as the ABC circuit, the current through the AOB LED is (12V - 0.7V) / 15,000 = 0.75mA. This is about 3x LESS than the ABC circuit.

Using a multimeter, I checked the resistance of both the ABC and the AOB resistors and they agreed with the resistor codes.

You can see the difference in brightness in this image:


The ultimate fix will depend on your experience with soldering and electronics.

How To "Fix" the ABC Switch
The solution to make the ABC switch look more like the Toyota OEM switch is to reduce the current in the LED and for extra credit, swap out the LED. I think just the change in resistor value (without swapping the LED) gets you most of the way there.

Easy: The total resistance in the ABC circuit needs to be 15kohms. Since there is already 4.7kohms on the circuit board, you can wire an external 10kohm resistor inline in the blue wire. Note that any resistor with power rating > 0.1W will be fine here.




Medium: A slightly more professional approach is to desolder the chip resistor that is on the ABC circuit board and replace with a 15kohm, > 0.1W resistor. I believe the resistor footprint is 0805. I had some 15kohm, 0.1W, footprint 0603 resistors in stock. I was able to use those.




Here's the new resistor soldered in place.


Here's the resulting light output.




This is already a nice improvement.

Since different LEDs have different light output vs. current and may have slightly different coloring, I chose to also swap out the LED. This leads to the more advanced solution below.


Advanced:
This solution does the resistor swap of the medium solution and also swaps out the ABC LED with the diode from the AOB switch.

Step 0 - Perform the resistor swap specified above in the "medium" section.

Step 1-2 - Desolder the AOB LED and bend the leads under the device. I chose to remove the switch-active LED. That way if I wanted to use the AOB switch for something else, it would still illuminate.



Step 3 - Attach the AOB LED to ABC circuit. I had to do this twice. The position of the LED is important. If the LED is too close to the resistors, it interferes with the mechanical operation of the switch. Try to place the LED as far forward as possible.



And the results look like this




The switch still works,


And finally here it is in the vehicle with the OEM switches,



Conclusion
I am satisfied with the results. Not the easiest hack out there, but it is not too bad either. This is a very niche application, but I hope this writeup helps someone else down the road. This probably also works with other switches that come from other suppliers, too.

 

Added to the weekend project list!

 

Great write up. I’m learning a little at a time about LED’s and resistors. Working on a project to dim my new Meso lights. I’ll be doing this mod tomorrow!

 

Glad you guys are going to try it. Let me know how it goes.

 

does anyone know what LEDs to get for other switches? Trying this project out on some light bar switches but the LED is just way too blue, even when going up to a 75k resistor!

 

Put a small peice of window tint on the led lol

 

I agree that even after the change, the switch is still a little too blue. I'm not sure if that is because of different plastic type or plastic thickness in the see-thru part of the switch. I've been searching tonight and some call the color "ice blue" or "sky blue", but I can't find any discrete components in that color. The closest might be "cyan" LEDs. I see both digikey and mouser sell cyan LEDs.

 

It’s been my experience with the AOB switches that they also are a bit on the cyan side compared to my factory switches. Much closer than the ABC Camera and CH4x4 blue, but still not an exact match.
That said, it looks like I’ll be cutting a resistor inline. Not skilled enough to tackle desoldering PCBs at this point…

 

I'm not sure if I agree with the Cyan, but would love to see results. I've just tried a 5mm "UV" led (a little too big so had to push it back a little) with a 9k resistor, and it looks pretty close at least in photos. It's still a slightly different shade in real life, but it seems way better than blue. I just ordered some "uv" 3mm LEDs, so will try that next and then play around again with the resistors.

And because this post would be worthless without pictures... "LED Light Bar" is the one with the 5mm, traction switch is the control

 

Doesn't help that it is damn near impossible to actually photograph these lights and capture how they look to our eyes. I tried that when I was originally talking with ABC about the light in their switch being off and too bright, but couldn't get anything to photo that would show how I was seeing it with my eyes.

 

Is there any reason it has to be a 10kohm resistor? I tried a 10kohm and it still seemed pretty blue, so I kept trying different resistors, and ended up putting in (I believe) a 47kohm resistor. I felt like it dimmed the LED closer to match the other switches. I've been running it this way for several weeks with no issues. I'll try to get a photo later tonight.

 

No reason it has to be 10k. If 47k matches a better match for the color, that's great.

 

These diagrams were very helpful. I found some ice blue LED's on

Treedix 750pcs 3mm LED Light Emitting Diode 15 Colors x 50Pcs LED Lamp Assortment Set Kit White/Warm White/Cold White/Red/Green/Blue/Ice Blue/Yellow/Pink/Purple/Multi Color Fast Flashing

amazon that matched closely and ended up using those + a 100k resistor (pictures don't give it justice, it's very close in person). Another annoyance I found was when the FRONT is toggled both LED's illuminate I fixed this by soldering in diode and cutting one of the traces.


https://timee1994.weebly.com/anytime-camera-switch.html

 

A lot of LEDs here too. Found these rebuilding GM clusters https://www.lc-led.com/
Read a good bit of info on them before purchasing

 

StayTunedOut did you find a matching color from that website? if so could you post the part please