Re: My 99 Boxster is possessed

My car has had problems over the past couple years that made me suspect that the ECU was dying. I'm now doubting that, or at least think that there may be additional issues.

Yesterday, I noticed that my rear trunk was open. Upon closer inspection I observed:

Cabin light on
Keyless entry nonfunctional
Lock button glowing red
Red dash light (near GPS antenna) on steady
Two fast beeps when trying to lock doors

Since we were headed out and it was raining incredibly hard, I turned the cabin light off to conserve battery power and decided to leave troubleshooting to today.

Today, I checked the car out and observed:

Trunk open
No keyless entry
Passenger door doesn't unlock with manual unlock of driver's door
Window lowers when opening the door
No cabin lights at all
Dash operational
Clock wrong
Car won't start
Windows nonfunctional via switches
Windows nonfunctional via convertible top latch (They don't lower at all when unlatching the top)
Rear spoiler functional
Trunk levers locked
No access to front trunk because of locked latch (but I have access to the rear trunk because of this next one!)
All fuses are good; however, when I remove and reinsert fuse D8 (rear spoiler), the rear trunk release actuates! (Which is good since my trunk levers are locked!) The solenoid held for approximately 10 seconds and then released.

I removed the ECU and returned back to car after an hour, when I returned, I saw that the windows were rolled down. The following happened while the ECU was not installed.

I put the key in the ignition and attempted to roll the windows back up, but they did not work (I kind of expected this, since the ECU was still removed. Although, I'm not sure if that would affect their operation.) I then heard a motor sound under were the trunk levers are to the left of the drivers seat. The levers remained locked. While I searched the fuse sheet for the correct fuse to yank, the windows started operating erratically. I removed fuse C3 (central locking/alarm system, power windows, inside lights) and both the windows and motor noise stopped.

At this point, I'm thinking that there must be something wrong instead of or beyond the ECU since it wasn't even installed during the last tantrum. Perhaps a ground short or the alarm module, etc. failing. I'm at a loss. Has anyone had a similar experience with their Boxster?

The car is stranded outside with the windows down. I hope I figure something out before it rains!



Edited 3 time(s). Last edit at 07/30/2012 03:24PM by Jayusa123. (view changes)

The ECU's functions are for engine management.
The functions you are referring to are handled by the CLU (Central Locking Unit) which is located under the driver's seat.
My WAG is that it's wet.
The symptoms you describe are very common when water gets under the left seat.
I suggest that you do not keep playing with the switches because you could very well fry the electronics if you haven't already.
Remove the left seat and the black box (CLU).
Dry the carpets and dry the electrical connectors.
Remove the printed circuit board from the CLU and dunk it in isopropyl alcohol for a couple of hours.
After that time shake it and wait a few hours for it to completely dry.
Reassemble and reconnect everything.
Cross your fingers and hope everything works again.
If not you will need a new CLU and then the car's keys and the car will need to be programmed into it.
Don't buy a used one because the CLU can only be programmed once.
Happy Boxstering,
Pedro

Pedro Bonilla
1998 Boxster 986 - 311,000+ miles: [www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)

---

Racecar spelled backwards is Racecar

"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"

"If you wait, all that happens is that you get older"... Mario Andretti

"Being second is to be the first of the ones who lose" ... Ayrton Senna

Thanks, Pedro. I'm going to go do that right now.

-jay

Well, that was definitely it. By the looks of it, this isn't the first time water has made its way in. See pictures here if they don't load below.





I had noticed some time ago (years) that once in a great while after I raised or lowered my top, the mirror defrosters would turn on. In addition, last year my cruise control stopped working. Is it possible these issues could be the result of the damage I now see in this control unit?

And for the holy grail.... Could it be possible that all my CEL/O2 sensor problems could be connected to this as well? Wishful thinking, I know. But couldn't a short here feed power into some other part of the system causing problems?

Thanks again, Pedro. You were spot on.

Now I just hope I can get the board dry enough to roll the windows up!

Jay



Edited 1 time(s). Last edit at 07/30/2012 06:45PM by Jayusa123. (view changes)

What are the codes?

I'll probably read them out tomorrow. I'll let you know.

Jay

In addition to drying it out you'll need to get any corrosion, mold, or mildw off the board. My suggestion would be to go to a drug store and get some 90% or higher isopropyl alchohol. DO NOT USE RUBBING ALCHOHOL. Put some in a bowl, wet a toothbrush, and scrub as much of the board as you can. Once the board looks clean wet it good one one side holding the board vertical and allow the liquid to run off. Then sling the board to get the last you can. Then do the other side. If you have some canned air you can use that, but whatever, do this in a dry area as the evaporating alchohol will chill the board and water will condense if the humidity is high. Then let it dry for several hours before reassembling it and applying power.

Good luck,

Al

Once all the above mentioned is done, you will need to UNPLUG the drain holes on your boxster. Pedro probably has a link to a diagram showing where they are.

Parking under trees will eventually clog the drains with leaves. Once the rear drains (around the top compartment) are clogged, the water will rise and run over the firewall and down to the floorboard where, IN AN ACT OF UTTER FREAKING STUPIDITY, Porsche and other car manufacturers have decided to bolt THE UNIT THAT WILL IMMOBILIZE YOUR CAR. Sheesh.

Thanks for the tip! I will definitely clear out those drains! I can't understand why in the world porsche (and others, apparently) would put something that is obviously sensitive to water at the lowest point of the car! Either make that thing waterproof or put it somewhere high, like where the ECU is. Uggh.

After cleaning the board and thoroughly drying, I reinstalled and was able to raise the windows (an hour before the rain came!); however, the car still isn't right. The doors won't lock/unlock properly, the hood latches won't unlock (I hear a motor in there) and there are no interior lights.

So, I whipped our my jewelers loupe and my multimeter! As of right now, I've found 8 broken connections on the board. The water seems to have corroded some of the copper traces where they were exposed. Like I said yesterday, this definitely isn't the first time this board has seen water... copper doesn't disappear overnight.

Once I've found all the breaks, I'll go in with my soldering iron and a steady hand. I'm hoping that the chips on the board weren't damaged by the water shorting them. With any luck, fixing the broken connections will restore the lights and other currently misbehaving systems. With a lot of luck, it'll fix the other nagging electrical problems in my car!

I'm keeping my fingers crossed!

Jay

Rear Drain Protector Screens

"A mile of highway will take you one mile. A mile of runway will take you anywhere."

Quote
Gary in SoFL
Rear Drain Protector Screens

I think those screens would still allow small things like pine needles through to clog the drains. They also doesn't do anything to keep the drains at the front of the channels under the clamshell (just by the top of the door frame) from clogging. Because of their position, most people don't even know they're there.

...and of course, there are the drains on either side of the battery at the front that should be checked.