Dr. Bob's Stereo Install - '94 premium audio -> Nav/Carplay/backup cam

Ah fair enough. I just got some components for the doors actually, basically the 6.5" version of what I put in the sub boxes.



Wont be fitting them just yet, will need to get some mounting rings made up for them. But a good excuse to sound deaden the doors while I'm at it also.

Just as an aside, it looks like the Polk MW5530 would have been a drop in replacement (and only $45 for the pair!). Mavin.com says it goes down to 45 Hz, so, the performance numbers are similar to the Tangs. The Tang magnets are clearly larger though, so, hopefully that makes a difference. Sort of wish I had seen this earlier - looks like a much easier solution. Anyway, next step is finishing up the firewall - I have the carpet back in place, just need to put all the panels back in.

Put the firewall back together. Not much to say or show here. Try to remember the assembly order.
Put the carpet back hand hold in place. Then put the top trim piece in place - be you do, check that all the trim clips are on the piece and no broken trim clips still in the car. You will be using a lot of new trim clips - the originals are 30 years old and brittle.

I put a second layer of sound insulation on the fire wall and partly mounted so it would overlap the harness without sticking. Then, I removed about half the jute sound insulation.



Because of this. . . you will need a lot of these:


Here is the top trim piece. Note the blue trim clips are new ones. A lot of them broke (as above) and had to be pried out of the car. Check to make sure you got the old ones out or you will be trying put a new one in an occupied location and break it.



Some of the trim clips look like this, where the 'peg' part slots into the typical trim clip spot and then you have an insert in the car to receive it (whitish circle). I think these were originally to make disassembly easier at these locations. I found two on each side panel. These are the same clips that I have holding the interior door pull cup. It is hard to find replacements but I found some at toyotapartsdeal the part number is
Part No.: 67771-33030
RETAINER, DOOR TRIM



Everything back in place. Looks okay, just need to vacuum and put the center console back.

Next up: Wire in the head unit!

I used the Metra harness, part number 70-8112. That is for the 92-95 cars with premium sound. there is a different one for the 91 cars and for the non- premium sound. The major difference for premium is that the premium cars have remote aplifiers and subwoofers (91 cars only have one sub). As I understand it, there is one main amplifier that feeds all the regular speakers and it also feeds signals to the sub amplifiers. There is one amp for each sub (so, 2 in my car). This is all just nice information that I found, I don't need it because I am keeping the stock configuration and using the metra harness.

Before soldering any wires, twist the wires together and put electric tape on the joints to keep them from shorting. THEN TEST IT IN THE CAR to be sure you have the right wires connected to the harness in the right places.



The Metra harness has line level RCA inputs to feed the amplifiers - you don't want to send too much power to the amps. So I needed to convert the regular signal from the Atoto P6 head unit to provide RCA connectors. Fortunately, it came with converters. So here I am soldering the line level outputs to the radio output harness.

Step one, put your parts down and warm up the soldering iron. Step 2, put the shrink wrap sleeve on one side of the wire.



Step 3, connect the two wires together. There are lots of methods here, this one is very good for most applications. Each wire wraps around the other wire. Learned this working for NASA Step 4, solder the connection. Use time and heat here. The idea is to take long enough at a high enough temperature that the molten solder wicks into the wire joint - it soaks it like when you touch a paper towel to some water.


After it cools, move the shrink wrap tubing over the joint and heat it up. The proper way is with a heat gun, but I used matches, which is why you see soot on the red sleeve. Look closely at this image and you see goo coming from the end - this is a sort of glue/sealant to keep the joint protected from moisture.



The Atoto radio has lots of harnesses, so, I bundled them into logical groups and wrapped with electric tape to keep the mess down some.



I stuffed the steering wheel receiver and the GPS antenna in a hole behind the emergency flasher button here:


Then I transferred the mounting hardware from the old radio to the new one. pics are of the new one without factory mounting hardware and of the old radio with the hardware.

And we're done . . . mostly. I think I have to take the facia off again to realign the vents. And, I have a set of Clarion speakers for the doors.

Overall, it sounds good. When I fiddle with the equalizer, the base is deep and loud (I don't know the propper audiophile terminology, sorry) it thumps plenty, a lot more than expected for 5.25" subs. Driving around, I can totally hear my audio books clearly. The radio is supposed to be wireless car play, but, I haven't gotten that working yet. It is running as an android radio. It streams bluetooth fine. I have tried to connect to wifi on my phone so I could update maps and such - that part seems pretty iffy.

Also driving around, it seems like the engine noise is louder - do I need to add some jute back?