Grandwazoo

I am not making this up. It rained like heck yesterday. In the middle of the thunderstorm we took a number of very close lightening strikes. After the storm I found the boxster had rolled its own driver side window down, the floor behind the seat had about an inch of water in it and the battery was dead. I charged the battery and hooked it up and lots of things turned on, the motor for the rear spoiler was running and clicking, the cooling fan in the front was turning on and off, buzzers behind the passengers seat was sounding and all the warning lights on the dash lit up.
I have left the doors open all day in the hot sun, charged the battery again. The top will not go down. The windows still work, the fan for the climate control still works, but the starter motor will not make a sound. I have not plugged in the harness going to the front of of the car yet nor have I plugged in the spoiler. I think the computer under the seat may be dead. Any ideas what would make the car roll its window down in the middle of an electrical storm?

extanker

i would make sure the battery is okay [test it] then i think you will need to get hold of test equipment and plug into the various control modules/ecms etc to see what is and what is not working . maybe your insurance will pick up the ball on this .......some of the symptoms you describe are classic bad/week battery .the not starting could be the alarm system and iirc it is under the pass. seat .....good luck drying it out though

ace37

If there was an inch of water in the driver's side floor your immobilizer module was likely submersed. It sits under the driver's seat and connects in to quite a lot of things. Some of them must remain powered when the ignition is off, so if it was indeed submersed, it would not be surprising if a few things shorted out. You can take the seat off with just four bolts, one at each corner, although you may need to buy an adapter to fit them. Then you figure out how to unclip each of the several wiring harnesses from the seat, pull it out, and see what things look like in there.

Ebay often has inexpensive used parts from teardowns if you have to go that route. You can pretty well remove and swap in replacement parts for whatever you suspect is damaged. If you replace the immobilizer you may still need to have it programmed to match your key's signature - I don't know but would expect that. Also the foam insulation in these cars sucks down water and I suspect would take a very long time to dry out.

Good luck!

kderry

This is what happened:
The drains under your clamshell are clogged. When the heavy downpour started, the wells under the clamshell quickly filled with water, then overflowed. The water cascaded down the firewall behind the seats and filled the basin under the driver's seat that the immobilizer sits in, causing it to fail. The windows rolling down is a common result of this.

So, your clogged drains caused the water intrusion, which damaged your immobilizer and now your car won't start. The windows rolling down caused a secondary water intrusion.
A new battery won't fix it. Send your immobilizer to ecudoctors for repair (cost should be about $500) and clean up the car side immobilizer connectors so that the repaired immobilizer will work properly when you get it back. There's a cheaper option that I've sent to you via private message.

Clear your clogged drains so it doesn't happen again.
I've seen this exact thing happen many times over the years and it's always the same cause and repair.

skullbyka

KDerry, I have same exact problem after deluge 1 week into ownership ☹️☹️. Learnt hard way about drains.
Please Can you pm with the cheaper solution to which you refer ?
Much appreciated

Macster

In case you don't hear from him the cheaper solution to which he was referring was getting a used security module from another car (left unsaid was it probably wants to be an otherwise identical car to reduce the risk of any model year to model year changes) and using an EEPROM programming tool to read the contents of the car's current security module EEPROM then transferring the contents to the used security module's EEPROM.

He provided no further info about which EEPROM programming tool or any other details.

He did mention he was an admin at another site. Here are his exact words:

"I won't share it here. If you want help, join the Boxster Tech Fans Facebook page and I'll help you. I'm an admin there and will add you if you request to join."

If you don't hear back maybe seek out the site mentioned and ask to join?

Tell him Macster sent you.