Hi all! I recently bought an 88 Bonneville SSE from a buddy (Black ext/grey int) and i have a few questions about it.
I did find alot of what i was looking for by searching, but from what i could see pretty much nothing is the same between years and models (LE, SE, SSE) and info on the 88 SSE in specific wasn't the easiest to find.

Stereo. I replaced the headunit with a normal ISO unit and changed the 6x9 3-way rear speakers, the 5 1/4 2 way fronts and kept the stock tweeters in the dashboard.
According to what i've read here the dash shouldn't have any speakers/tweeters at all there, only the speaker grilles, with the Performance Sound System. Aftermarket?
I managed to find the color codes for the stock wires here and rebuilt the stock wiring to match ISO standard for easier replacement later, but i seem to be having some sound issues though.

I read that the rear speakers should have an amp somewhere. Where is it and how powerful is it? The should be a button/switch to turn it on as well, but i can't find any switches that makes the sound better or different in any way.
Was this only with the BOSE system and not with PSS?
Regarding the sound issue: With all speakers playing at once, the sound is horrible. No bass and choppy mid and high range. If i fade it to the rear and one side (One speaker playing) it sounds good though. Is this the stock amp just sucking at running my speakers? I haven't replaced or run any new wires, all wiring from headunit to speakers is stock.
I'm assuming this has something to do with weak amps for the speakers, but i've run similar setups directly from a CD-player before without any issues like this at all so i suspect the factory amp, if there is one, is too weak for the job, or just gets the wrong kind of signals from the headunit. Suggestions?
Are the antenna plugs different between the different years/PSS/BOSE/Models or can i use any convertion plug. With four weeks delievery time i don't really feel like ordering the wrong one. Not even once.

There is also a wide range of warning lights on while i drive. Well, atleast the Brake and ABS light is. The Brake light is because of the parking brake switch. I can deal with it being lit as long as i know why tbh. ABS concerns me a bit though since these cars seem to lack and ordinary master cylinder and booster. If the ABS pump goes, so does my brakes?
During the winter i've noticed that the ABS works, at times, dispite this light. A couple of times the pedal has been rock hard as well, but that has been after heavy acceleration (No vacuum) like an ordinary brake system would without vacuum to the booster.
Is the master pump gone/going or is it just another case of "Learn to live with it"?
I might also add that classic cars is my passion and way of life, ABS is not really vital. I've never had a car with it before and i'm not that desperate to get it now.

Removing the bulb for that light sprung to mind, but if it'* something serious i might as well keep it there and actually fix the problem and not remove the reminder.

I also have a water leak from the sunroof. It looks like the entire mechanism on the passenger side is rusted to pieces. Common problem? Any hotfixes that look more decent than black duct tape and doesn't cost a fortune/take "for ever" to do? It doesn't have to work, the A/C works, but i would like it to stop leaking water, the winters here are pretty rainy...

How are the transmissions in these cars? The previous owner replaced it at 180K miles, now going on 290K-ish miles. First gear can be rough, but it doesn't slip more than what seems normal and acceleration is good.

The power lock servos actually work, but the locks seem to be too hard for them to push up and down (All of them). Will a quick lube of visible joints inside the door be enaugh to fix that or is everything closed up and have to be replaced?

Other than that the car seems to think it'* too cold here in Norway, the compass points south. Always. But watching a working compass on Norwegian roads would only make you dizzy anyway, so that'* ok. And the Driver Information screen is dark most of the times, but sometimes it lights up, does a few checks and concludes that nothing works, everything needs a service and all doors are open. So every time i start the car and that thing is dark, i'm happy.

Did the face-lift interior come in 89 and the exterior in 90? I've noticed some considerable differences in interior design and i was wondering if i HAVE to get a car of the exact same year and model if i want interior parts. Getting an LE or SE for interior parts seems like a waste of time since they aren't even remotely close to looking the same inside.

That'* all i can think of for now. I'll try to take some pics after i've cleaned it. Just finished a 40 mile journey on wet, salted roads. It'* more white/grey than black atm.

First off, welcome to the club!

Radio
Bose was not a option until 97 in bonneville. You have Performance sound with the GAIN amp. the amp is located under the passenger seat in the floor under the carpet. its in a black plastic box with slates cut in it. The AMP only powers the rear speakers but is on a seperate circuit so when you have it off the rear speakers are still working without it. you should have a ON/OFF switch with a small slider next to it on the console infront of the shifter. at your mileage im sure the switch doesnt stay engaged anymore so you may have to wedge something on the side of the switch to make it stay down. the button should have a picture of a music note on it.

Compass
if you want to recalibrate your compass you have to hold the mode button until CALIBRATE starts flashing on the screen when it does you drive at ~5 in a tight circle in a parking lot without alot of power lines over the top. when calibrate stops flashing you can stop the vehicle and the compass will be calibrated.

Locks
you may need a bumper kit for them. i have this problem on two of my doors. you have to hit the button several times for them to move, if they do at all.

Brakes
Someone else will speak up on the ABS system. but i can say if the pump fails you will lose ALL brakes and it was a comon problem noted at our Highway/traffic safety division here in the states.this braking system was only used 88-90. i do know generally if you are getting a hard pedal you need to replaced the accumulator (the black round ball on the top of the master cylinder) the easiest way to know if it needs replaced is if you hear the pump kick on everytime you hit the brakes, even in park.

Parts interchangibility
The interior facelift came in 89, so parts for you model will be 1988 SSE models only. 89-91 recieved all the seat switchs onto the center console. a new center console, and new steering wheel. alot of interior and exterior parts are SSE specific, so when looking for things try to make sure they are from a SSE.

Thanks for the welcome and reply!

All i have in front of my shifter is a small storage compartment, but i haven't really looked that hard yet. I'll take another round through the inside looking for buttons and unwanted little boxes that ruin my sound. If the amp is under the pass. seat i can pretty much guarantee it doesn't work since that seat has taken the worst of the sunroof leaks.

Does the compass stop moving (Stuck at south in my case) if the calibration is bad? I got a huge parking lot right outside, so calibrating will be a peace of cake.

We seem to have the same problem with the locks, but usually i drive alone (Global warming ftw!) so i only need the driver door to open, the rest i can open manually inside if needed.

If the pump kicks in while stationary, in park, the accumulator is broken, right? Does it work like some kind of brake booster? Or has a similar effect on the brakes? If it does, i don't have a problem.
I expect my brakes to go hard when i have full throttle, but i wasn't expecting a brake system with electricly servo assisted brakes to do the same thing.
No matter what i don't like that it'* noted as a common problem by the US Highway/Traffic safety division. That is bad. Very bad. I'd feel more comfortable driving a car i knew could burst up in flames at any time. Atleast i can stop.

Other than that the brakes seem to be pretty weak for a car with slightly sporting ambitions. Then again i'm used to Volvo brakes (200-700 series) and they just fing stop!

The parts thing kinda sucks. This is, afaik, one of two 88 Bonneville SSE'* sold new here (They cost more than a top-spec Merc *-class back then), and finding a parts car in the same color and year here is... Impossible.
As far as i know they had certain interior/exterior color combos, and black/grey is one of them. I know with the later model trucks (They actually sell over here) the dark exterior colors only came with light interior colors. With black ext, the only int color is grey.

I think most of my research is done, time to start tinkering.

the pump should kick on when u start the car, but it shoudlnt kick on everytime you hit your brakes. the accumulator hold pressure in it to give brake assist when u hit the brakes, basically so the pump doesnt have to pump everytime the brakes are hit. the accumulator can have 2000psi in it at any given moment. as the accumlators age, they dont hold enough pressure in them, causing the pump to have to run constantly. when the pump runs alot, it gets hot and can burn out. if the pump burns out, you lose ALL brakes. the accumulator runs around 200 bucks brand new through GM. i recently replaced mine for a piece of mind.

We've seen several SSE'* from Norway in the past, we'd love to see some pictures as euro-spec bonnevilles were a bit different than our North American spec cars.

devon

My bad on the GAIN switch, i forgot the switch and adjuster were part of the 89 changes. yours is just on all the time

Knowing how the accumulator works, i can pretty much guaratee it'* broken. The brakes are fine as long as i don't brake hard/fast.

As far as i've seen from pictures mine isn't different except painted front corner turn signals and aftermarket (quite ugly) turn signals on the front fenders.
The stock lights aren't marked with "E", only "DOT", so they were just painted and replaced with some that are. The lawes have changed now though, so any equipment marked "DOT" is now equal to "E" so i can put the stock ones back in use.
Not sure if it'* stock or not but my rear turn signals are orange as well. Not sure how they are over there, but all red taillights seems to have been the trend up until recently.

I understand that the taillights are made up of three pieces and the middle one has the coloring. So if i remove that part and tint (Spray or film) the clear part (Inner?) then put the the two remaining back together, my Bonnie'* tail is all red.
I plan on making the entire rear panel glow red as driving lights, so i'll need to get a dual socket thing for the tails and probably just learn to live without backup lights. These cars are pretty unusual here so i think i can get away with having red turn signals if i say it'* stock. Chances are they've never seen one like it anyway.

I'll get some pictures up during the weekend.