Ownership Verified: My 98 Buick Park Avenue Ultra

As a DIY you could open the unit, remove any dust and dirt, and hose the volume pot with contact cleaner. These things normally don't die in an instant, but gradually.

That being said, $150 for removing and soldering in the part does not sound too outrageous.
No, he said it would be $150 to fix/replace the optical encoder, not replace the pot. He didn't look at my stereo or listen to what was happening, he just said it was the optical encoder. I don't believe that, I have enough experience with this stuff from doing the electronics in my bass' to know a bad pot when I hear one.
Especially if you do your own bass maintenance, fixing the stereo should be a fun weekend project.
Can you spot what's different between these two stereos?


One has a CD player, the other does not, it's a very subtle difference, especially while looking at small pictures on your phone. So subtle even I didn't notice it at first despite looking at one of these things every day for over 15 years. And I'm REALLY glad I did because I had several possible donors lined up that all lacked the CD player. Eventually I found one from a wrecked 2000 Park Avenue (non Ultra) that looks to be in good shape and was for a bit less than many others I saw listed. It should be getting here next week and hopefully that will be the end of my sound issues.

My only two concerns fixing my original unit is going to be finding a replacement pot and figuring out how to remove the faceplate.

Also had to take the car to a local tire/service shop. My rear passenger tire developed "a hole", not a nail or screw but just "a hole". I last filled them up sometime in Feb, had the low pressure sensor go off, and they were all still at 40 while that tire was down to 25. Filled it up and checked it the next day and it was already down 2-3psi. As an aside, I don't know why that sensor doesn't go off until a tire is at almost half of what it should be, it seems silly to wait till you're close to the danger zone.
As an aside, I don't know why that sensor doesn't go off until a tire is at almost half of what it should be, it seems silly to wait till you're close to the danger zone.
Could simply be to account for pressure changes because of temperature and not annoy you with constant warnings. Does your car come with in-wheel sensors or does it automagically detect this through the ABS sensors or something? The latter might just not be accurate enough - I know my dads old car that used this system would only send a warning when you could actually see the tire being noticeable lower pressure than the others.

Since my car displays the readings from the (in-wheel) sensors, I can actually watch the pressure fluctuate up and down by quite a bit depending on whether it's cold or whether the car has sat or been driven in the sun for extended periods. It's definitely more than I would've expected... and definitely enough for an "early alarm" to trigger despite all being well. I actually did have my low pressure alarm trigger on cold winter days when changing to the winter wheels on a particularly warm/mild day...

edit: half pressure seems a tad excessive to account for temperature, I will admit. but my dads old car would also easily go that far before triggering an alarm.
I honestly have no idea how my car goes about it, but considering the age I'm sure it's the most primitive system compared to how it's done today. It doesn't tell me which tire is low or by how much, it just gives a blanket "check your tires, something is out of whack" message.
To my surprise the stereo arrived today and it looks to be in good shape other than being a bit dirty. I'll clean it up and put it in sometime this weekend. As an aside, for some reason almost no one bothers to just unplug these things when get removed, almost all of them have the wiring harness and antenna simply cut off, this salvage unit included.

Can't remember if I mentioned it or not but I also recently bought my very first dashcam, which I still need to setup. It's nothing super fancy so there's no wifi or GPS built in but it does have dual cameras so I can cover my own ass. I genuinely hope that I never have to say the phrase "I've got it on dashcam!" and the only thing it ever captures is me singing along to Bob Seger.
Ok well this sucks ass.

I put the new unit in today and my problems are even worse than before and I've no idea what the cause is. It will power on but the volume is really low and turning the volume knob doesn't affect it all. Using the steering wheel controls does work but only for a second, soon as I take my finger off the volume goes right back to where it started.

I don't know if I've done something wrong or there's another issue I don't know about or if this unit was junk before I got my hands on it. This was meant to be easy and it's quickly becoming a nightmare.
Does the PAU have an external amp? It was all the rage for high-trim cars in the 90's...
I don't know, there might be. There's a 10 or 12 disc cd changer in the trunk (that I haven't used in over a decade) and there might be an amp somewhere back there. I'll take a look tomorrow.

I texted an uncle of mine who used to do this kind of thing for a living, he's of the mind that this stereo was fucked before I ever got my hands on it. One thing of note is that this unit had what looked like either an extension or adapter on it that had several splices in it along with some cut wires. I don't know if was from getting hacked out by the salvage yard or if it had always been like that but it's clear someone had been in there before.


According to a DIY car stereo forum, GM had these basically locked to your VIN and only a dealer could recode it. I don't know if that's true because I imagine the damn thing wouldn't work at all if that was the case.

Anyway, my uncle has a lot of gear laying around and he's going to see if he has anything that I can use. But if that falls through I'm also researching aftermarket units as well, it's just hard to justify spending that kind of money on something like this and the idea of having to make a custom wiring harness is already giving me night terrors. I do NOT do wiring like this, it just drives me insane, I've thrown out entire working strands of xmas lights because they were too badly tangled, and this would be on a whole new level.
Looks like an amp to me.


I've seen it before but it's so far below my normal line of sight I had forgotten all about it.

I've looked into this radio being locked to the original cars VIN and it seems it's from what they called Theftlock. If you look just above the AM/FM button you'll see the logo and a single LED. The idea is if power gets cut, even from just the battery going dead, these things supposed to become totally useless. Sometimes you can fix it yourself and sometimes you have to take it to a dealer to get it fixed, there seem to be conflicting information.

dterek 3.png

But I still don't think that's my issue because the salvage stereo does work, but only partly. That little LED didn't lock up and there was nothing on the display about it, apparently it's supposed to show LOC when it's happened.

I've already put my original stereo back in just so I have something that kinda works, but I'm not eager to tear into my dash yet again to reinstall the salvage unit and try to unlock if it (if that is my problem) when I'm not even sure it's just not plain old fucked.

So aggravating.
Yeah. TBH, I'd just hit Crutchfield. One stop shop for everything you need, and paint-by-numbers instructions for making the wiring harness go.

This all assumes your actual problem isn't the amp cutting in and out.
I don't believe it's he amp, I'm reasonably sure of that. Because I can literally grab the knob and get it to either go to max vol or behave depending on how I wiggle/turn it. It's very temperamental, it will work fine on my way to one place but when I get back in the car it's decided to throw a hissy fit.

I have been looking at Crutchfield, it looks I have two options, either $90 or $150 for an all in one kit. Plus another $60 if I want to retain my steering wheel controls. Apparently they will wire up an adapter cable for you so it will be just plug and play, but I don't know if they'll just do that automatically or if they charge extra, I didn't see an option for it in the shopping cart.

If I can get it apart without damaging it, I plan to take the face plate off the salvage unit to see if there's a part number on the volume pot. Maybe I can find a replacement and slap it into my original unit.

Basically my options right now are

1. Just deal with having a bitchy radio.
2. Hope my uncle has something on hand and can help me out.
3. Repair my stock radio.
4. Bite the bullet and get an all in one kit from Crutchfield.
5. Say fuck it and just use a blutooth speaker.
Installing a third party headunit in there still not in the cards?
Installing a third party headunit in there still not in the cards?

Looking at crutchfield for the Mexican Wart, and I'm not finding many if any stereos in stock at the moment.


less than $100 ones apparently are out of stock.
You may have to look at the used market to find something in that price range that will be good. @Punisher Bass will surely notice an underperforming stereo relatively quickly (and be annoyed by it just as fast).

On the other hand, it may be worth it to spend more on a quality headunit now. Especially if he plans to keep the car a while (as he does) and he may benefit from features not available on the stock stereo, like Bluetooth, integration such as CarPlay or Android Auto on higher-end devices, and hands-free connectivity. It is, of course, very easy to spend someone else's money, but that's kinda how I see it if he could afford it.
It's looking more likely I'll have to install an aftermarket stereo, but I'm not throwing in the towel just yet.

I had a peek inside the salvage unit yesterday and, ugh. It seems there's about 800 different nuts and torq bits holding this thing together and it's structured like an onion. You peel off one layer only to find you need to take something else off because the heads are accessed from a different side. Without feeling like I was trying to disarm the bomb before it went off, I got a look at the pot and found almost nothing useful. All I saw were the words "ALPS" and "JAPAN", no serial or part number.



I fear digging much deeper into it not just because of the complexity but because I'm probably going to have to return this thing and I don't want to risk breaking something, assuming it wasn't fucked already.
I heard back from my uncle today, he has an old Pioneer DEH-2300 laying around, he's going to have his guys at Best Buy make an adapter harness, antenna adapter, mounting kit and so on. All great in theory and I'm grateful, but I don't know if it's going to work. According to the Crutchfield website it's too deep to fit at 6.6 inches while my car has a max of only 5.7 inches. I'm supposed to see him on Saturday and he'll give me the stuff then, hopefully it all works out flawlessly.
I honestly have no idea how my car goes about it, but considering the age I'm sure it's the most primitive system compared to how it's done today. It doesn't tell me which tire is low or by how much, it just gives a blanket "check your tires, something is out of whack" message.
If the system has been working without maintenance since 1998, I’m sure it’s measuring tire circumference via the ABS system.

“Proper” tire pressure sensors aka wireless battery powered thingamajigs inside the tire are never this trouble free.
Oooookay, update time!

The salvage yard stereo was sent back from where it came and got my hands on the Pioneer unit from my uncle this past weekend. As promised it came pretty much ready to go with all the mounting hardware and custom wiring harness adapter.



It wasn't 100% plug and play though, after doing a fair bit of fighting trying to put the dash bezel back in place I realized there were two small plastic tabs on the new mount that were getting in the way. So I just pried the little fuckers off with a screwdriver, gave things a few good thumps and everything went into place. The other very small issue is the bezel for the stereo itself, there's no way in hell it's going to fit as is. So I can either start whittling away at my dash bezel (not happening) or the stereo bezel, and that's what I'm going to do. I've been using my dremel on it slowly and it's a little better but I think it's just going to be too damn big to fit. Not a big deal at all.



I asked my uncle what I owed him for all this and he refused to take any money, so I can't really bitch about something that was free.

Listen to it for yourselves. Note that with the exception of the stereo itself, the rest of the audio system in my car is 100% 20+ year old OEM spec and I haven't messed with any EQ settings, it's just as it came out of the box. I think it sounds pretty damn good.