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2010 Mercury Milan Hybrid, 1993 BMW 325i convertible
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Discussion Starter · #1 ·
I've got strangeness going on with my ACCII system.

The amplifier is working, the new servo is in place. The only pod that isn't working is the leg flap and I'm not ready to tear out the dash right now so I have that line plugged off. It worked beautifully until a couple of days ago, when I got new pods for the defroster vents and the one fresh air flap that's shot. I installed them, fired it up and - nothing. No fan, no heat, no cool air. It acts just like it did before I replaced the servo. Bad servo, right? Except I hit Defrost and get all kinds of heat out, no problem. I turn off Defrost and the servo switches and closes off the heater core. So I start playing with things and for some reason I decide to force the fresh air flap open by squeezing the largest vacuum pod on the passenger side. Boom, fan kicks in and I get cool air. I turn it to max heat and I get nice warm air. I turn it back to cool, and I get cool air. So I shut off the car and let it sit for a few minutes, then try it again. No fan, no heat, no cool air. Once again squeeze the largest of the passenger side pods to force the fresh air flap open and the fan kicks on again.

The last two days I've left the glove box out to experiment. When I start the car, it doesn't matter what temperature the ACC is set to, I've got nothing. As soon as I squeeze that fresh air pod everything works. The fan speed cycles up and down properly, the heat kicks on when it's supposed to, the fresh air flaps open when they're supposed to, the center flaps open and close when they're supposed to. I've checked the new pods and they're doing what they're supposed to. I can't find any vacuum leaks. The only thing that I can tell is happening when I first start up is a weird noise - like the fan is running at super slow speed - but it's coming from the vacuum relays behind the glove box. I squeeze the fresh air flap pod and everything works until I shut the car off the next time.

I've never read anything like this problem. I've thought that maybe one of the vacuum relays is going bad and it just needs the extra boost of vacuum that happens when I squeeze the fresh air pod, but I don't know if that's even possible. Does anyone have any ideas? I don't want to drive with the glove box out for the rest of my life.
 

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Scott, There's a gentleman by the name of George Murphy over on the MBCA board who knows this ACCII stuff inside out. You might throw a post up over there and see if he'll respond.
 

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Administratoris Emeritus
2024 SL770
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No heat except on Defrost is a classic symptom of a failed ACC amplifier.
 

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Since the fan doesn't blow until you squeeze the pod, I would tend to look toward electrical. In the manual (83.1-605), it shows several vacuum switches that are closed by a vacuum of 78.5 mbar. Could there be a small leak that happens when the engine is stopped, and the vacuum requirement to one of the switches is not met without some coaxing? I'm certainly no expert on this or any other vacuum system but it's a thought.
Good Luck.
 

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Premium Member
2010 Mercury Milan Hybrid, 1993 BMW 325i convertible
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Discussion Starter · #5 ·
isthisdave said:
There's a gentleman by the name of George Murphy over on the MBCA board who knows this ACCII stuff inside out.
I'll try over there - thanks!:D

GermanStar said:
No heat except on Defrost is a classic symptom of a failed ACC amplifier.


Except it works when I squeeze that vacuum pod, and I have an extra amplifier (I got it from you guys a few months ago) and that doesn't change anything. :confused:

BenzToy said:
In the manual (83.1-605), it shows several vacuum switches that are closed by a vacuum of 78.5 mbar.


I've been leaning toward that, but I'd like some independent corroboration before I start just throwing new parts at it. I've tried that before and it gets expensive. ;)

Thanks all!
 

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ScottinSoCal said:
I'd like some independent corroboration

Everybody chime in.




ScottinSoCal said:
before I start just throwing new parts at it. I've tried that before and it gets expensive. ;)

Don't we all know it.


:sawzall:

rule

:sawzall:
 

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Premium Member
2010 Mercury Milan Hybrid, 1993 BMW 325i convertible
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Discussion Starter · #7 ·
OK, well I think I found out what the problem is. Or at least, what a problem is. Apparently I got one of the less successful rebuilds on a servo. :(

This afternoon I ran an errand and it worked as expected. This evening I drove home and got no heat. Plenty of fan, once I squeezed the large pod, but no heat, not even in Defrost mode. I left the engine running once I got home and checked under the hood. The case of the servo is too hot to touch - much hotter than the hoses going in and out of it. I think it may have fried the new amplifer, too, because there's a burned electronics smell coming out of the glovebox opening.

The good news is, the servo is under warranty. The bad news is, I don't think the servo warranty covers the fried amp. Maybe it had a warranty, too? I bought it less than 6 months ago.
 

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Always Remembered RIP
1973 450 SLC AMG, 1995 Chevy Tahoe
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It's sound like mine it simple have a life of it's own. It's crazy. I mean what was the temp out side , the humi. is it day or night . A perfict sevo does what it want when it feels like!!!!!!!!!!!!!!!!!!! So I guess congratulation for a job perfictly done:thumbsup:It once came on and blew out my match. and went right off.
 

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Forum Administrator , RC Colas® & Moon Pies®
1981 380SL 151K: 2005 S500 116K
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Claude says he won't work on the Climate control if I install this system. I realize it's not original but the above comments make me wonder if I want to go forward with a new OEM servo or try something that may be better.

Digital AC Servo Upgrade Kit
 

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2010 Mercury Milan Hybrid, 1993 BMW 325i convertible
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Discussion Starter · #10 · (Edited)
Just a piece of trivia for anyone with the ACCII system:

The trip out here went almost flawlessly. Mechanically, the car ran great. But about half way through the trip the engine died and I was lucky enough to coast into the only service station in a nearly 80 mile stretch. First the tachometer stopped working, then the radio died. I hit a small uphill stretch and the car started to buck. I pulled off onto an offramp and saw a service station, so I headed for it. The car died as I slowed down below 20 mph and I coasted the rest of the way. The battery was completely dead.

They charged it for me, and while it was charging I disconnected the electrical connections to the servo. Once the battery was charged up and we'd covered the fact that they didn't have an alternator that would fit a 30 year old Mercedes, I continued on to Vegas. On the way I discovered that the old alternator was working, as evidenced by the fact that it continued to charge the battery and when I stopped for gas in Vegas the car started right back up again. Whatever is wrong with this servo is wrong in a way that drains power faster than the alternator can charge it.

I'm going to change the alternator on principle. The old one may be weak, because I figure nothing should have been able to discharge the battery with the car running, even a bad part. But if your tachometer and radio die on the road one day, start looking for a place with a battery charger. You're gonna need it.
 

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ScottinSoCal said:
...I figure nothing should have been able to discharge the battery with the car running, even a bad part...
Without alternator/dynamo, most of cars could not run for longer than 3-4 hrs (or near, depending on size of battery).

Spark in the plugs is major power consumer
 

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Forum Administrator , RC Colas® & Moon Pies®
1981 380SL 151K: 2005 S500 116K
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Well, the nail was removed from the Avalon's rear tire so it will resume its duties as the vehicle that I drive to work most of the week. Unfortunately, the AC suddenly stopped blowing cold air. Off to Advance Auto for the recharge kit with a hose w/gauge. One can into the Avalon et voila! Cold air again.

Hmmm...what's this? A SECOND can in the box? What other vehicle do I have that currently blows non- chilled air though the vents? Did someone say...
an '81 380 SL?? Why yes! And it's been converted to modern refridgerant, too.

Another can emptied and...

The air is cold, boys.

The air is cold!

Top down, sun is shining and cold air is being pumped onto my hot little hands as I cruise.
 

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Outstanding Contributor , Bob's Your Uncle!
83 280 SL- 5 speed-The PIG
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32,362 Posts
I fixed my AC system last year...for good.
I removed it.


PS.... It sounds like you probably needed a new Alternator anyways, Scott. Tough to break down near / in Vegas
 

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1981 380SL 151K: 2005 S500 116K
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nobby said:
PS.... It sounds like you probably needed a new Alternator anyways, Scott. Tough to break down near / in Vegas
Yeah...poor Scott. "Here I am, stuck in Vegas with NOTHING to do.
 

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Administratoris Emeritus
2024 SL770
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ScottinSoCal said:
OK, well I think I found out what the problem is. Or at least, what a problem is. Apparently I got one of the less successful rebuilds on a servo. :(
This is a shot from the Servo box -- just food for thought. Out of the hundreds of aluminum body servos we've sold, the fried amplifier thing has come up perhaps three or four times. BTW, a faulty servo can drain your battery when your car is not running. In any case, you are certainly covered under warranty.
 

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