HVAC assembly tear down.
I hate my life, but whatever.............
In my never ending quest to have what I want, I finally got some time to rip apart the HVAC assembly that I butchered years ago. I got a doner HVAC assembly about a year or so ago b/c I knew that by completely gutting the plastic base for the lighting (in order to accomodate the LED strips I put in), I would need an untouched one. WELL, I got one from an '03 hoping it would be identical, but it wasn't. Remember that in '05, Toyota installed "smart airbags" and so the circuitry of the passenger airbag light was slightly different and so was the circuit board on which it shares with the HVAC controls. Yay (stab me in the eye please)
I want to share this with anyone who wants to tear it apart like I did. IT'S NOT FOR THE FAINT OF HEART. Lots could (almost did) wrong.
Not going to go into how to take it the back side apart, it is self explanatory.
BUT, here is a great thread on how to do so (helped me):
How to take apart the 4th gen A/C controls
After taking the backside off, you need to take off 3 screws that secure the circuit board in place. Then look to the 3 ribbon cables that need to be detached from the board. Very easy, on the sides there are locks that need to be lifted, then carefully lift the ribbon cable itself. They are very ridged, but still be careful (break these and it's game over).
Another angle
There is a ribbon cable that runs down the toward the bottom of the assembly, there are 2-3 screws that secure it. Remove them (no pics).
You will then observe the pins that run to the display screen. Yep, those pins are secured by (surrounded) white plastic that need to be dremeled out. Again, be careful, BUT they are ridged as well (I hit them with my small attachment but nothing happened. If you don't have a steady hand, don't even try this).
After dremeling the plastic tabs out of the way (took me 5 minutes), you can carefully bend the pins so that the screen can be pushed slightly aside. While doing this, the buttons of the "mode/reset" will come apart AND you need to be careful of the LEDS that are in "ridges" (on the opposite side of the clock controls) in the assembly. If you are not careful, you will rip them off the board.
After/Before
AS you can see what I did, I gutted the back side of the assembly so I could lay down some LED strips. I glued a rectangular piece of plastic (I had a ruler that was the perfect size) that I used as a based for the strips. Doing this permanently altered the assembly so I couldn't bring it back to normal.
Back side: (observe they are nearly identical, but have slightly different back side toward the passenger airbag light, I had to shave off some plastic so the white plastic wouldn't hit a chip on the board when fully installed. Also, you loose a screw that secures it to the board, no biggie really)
A look at the difference between an 03 and 05 (note the left side of the board, it is different). Also note the top one (from my 4R, the display screen is darker due to the polarization film)
when the board is laid down and screen popped in. As I mentioned, you loose a mounting screw, but it IS secure.
After you screw and tighten everything up, proceed to install stock bulbs or 12V LED (me). I got these from [MENTION=210043]Johns06yota[/MENTION]. Practically plug n play, but do notice that the wired part of the base (LED) has a wire on it, this is the negative (99% sure). This part has to come into contact with the negative part patch of where the stock bulb goes or it won't turn on (LEDs are polar sensitive remember). I haven't reinstalled it yet, b/c my bases are covered in solder from the last time I had someone reled them. Very messy. Anyway here are some pics:
Positive/Negative:
This wire on the base is the negative:
Base polarity (this picture is before the assembly was reledded. Person who did this was very sloppy......urghhhhhh)
So to sum up, if you want to install LED strips in the back of the display, please don't. It will look like this (crap):
BARF
If you do the reverse polarization mod, be sure to get a 12V LED to light it up, b/c if not, the display will be barely noticeable during the day. I'll post pics when she is all installed and sorted out.
