Go Back   986 Forum - The Community for Porsche Boxster & Cayman Owners > Porsche Boxster & Cayman Forums > Boxster General Discussions

Post Reply
 
LinkBack Thread Tools Display Modes
Old 12-30-2017, 04:51 PM   #1
Registered User
 
Join Date: Dec 2017
Location: Canada
Posts: 73
Question What is this black box in rear trunk near ECU?



What is the black box to the right of ECU on this 1999 986 manual? This is the kind of wiring you do NOT want to find when troubleshooting a no-start situation. The mystery box has 2 wires coming out of it: red and black and they connect to a yellow and black wire from the harness.

It looks maybe like a remote starter as I "think" the yellow and black are ignition and starter.

Any guesses and any idea where the yellow and black wire should go instead of this box ? Thanks in advance.

Porsche-Eh is offline   Reply With Quote
Old 12-30-2017, 06:55 PM   #2
1997 Tip, 2018 Macan
 
rexcramer's Avatar
 
Join Date: Aug 2015
Location: Upland, CA
Posts: 1,338
Garage
GPS vehicle locator, i.e. Lo-Jack type device?
rexcramer is offline   Reply With Quote
Old 12-30-2017, 11:54 PM   #3
Registered User
 
Join Date: Feb 2017
Location: CO
Posts: 989
Wow, what in the heck are all those solderless connectors going to? That’s a lot of hacked in wiring!
Geof3 is offline   Reply With Quote
Old 01-01-2018, 09:14 PM   #4
Damn Yankee
 
TeamOxford's Avatar
 
Join Date: Mar 2013
Location: Dallas
Posts: 1,117
Garage
Quote:
Originally Posted by Porsche-Eh View Post


What is the black box to the right of ECU on this 1999 986 manual?
I believe that's the "flux capacitor". Be careful around 88 MPH.

Just sayin'............

TO
TeamOxford is offline   Reply With Quote
Old 01-01-2018, 09:55 PM   #5
Motorist & Coffee Drinker
 
78F350's Avatar
 
Join Date: Jul 2014
Location: Oklahoma
Posts: 3,653
Garage
Quote:
Originally Posted by TeamOxford View Post
I believe that's the "flux capacitor". Be careful around 88 MPH.

Just sayin'............

TO


The black box would not concern me as much as the other wires in the picture. I'd just rip it out along with the rest of the hacked up engine harness. Unless you know details of what that mess is meant to do, it will probably solve a lot of problems to replace it all. You have me curious if there is anything strange on the other side of the firewall... Stock 2.5L?
Is it your car? ...more pics plz.

...and it may take me a couple days to get around to it, but I have full schematics available if you need them.
__________________
I am not an attorney, mechanic, or member of the clergy. Following any advice given in my posts is done at your own peril.

Last edited by 78F350; 01-01-2018 at 09:59 PM.
78F350 is offline   Reply With Quote
Old 01-02-2018, 10:31 PM   #6
Registered User
 
Join Date: Feb 2017
Location: CO
Posts: 989
You posted much better pictures on the “R-list” site. And based on those, you need to loose all that junk, whatever the heck it is.
Geof3 is offline   Reply With Quote
Old 01-03-2018, 10:07 AM   #7
Motorist & Coffee Drinker
 
78F350's Avatar
 
Join Date: Jul 2014
Location: Oklahoma
Posts: 3,653
Garage
Quote:
Originally Posted by Geof3 View Post
You posted much better pictures on the “R-list” site. And based on those, you need to loose all that junk, whatever the heck it is.
Yes, the other post is better. I'm still curious about the engine - and the rest of the car. The other connector in question in the R-list post is for the trunk light. Here's a pic of it on a harness:
__________________
I am not an attorney, mechanic, or member of the clergy. Following any advice given in my posts is done at your own peril.
78F350 is offline   Reply With Quote
Old 01-03-2018, 01:44 PM   #8
Registered User
 
Join Date: Feb 2017
Location: CO
Posts: 989
Quote:
Originally Posted by 78F350 View Post
Yes, the other post is better. I'm still curious about the engine - and the rest of the car. The other connector in question in the R-list post is for the trunk light. Here's a pic of it on a harness:
Curious as well. No idea why there would need to be all of those fuses inline in that section. Very odd.
Geof3 is offline   Reply With Quote
Old 01-03-2018, 08:34 PM   #9
Certified Boxster Addict
 
Join Date: Nov 2010
Location: Los Angeles
Posts: 7,669
Wow, what the heck is going on in your trunk?

You might want to ask Homeland Security to take a quick look ... Just be careful and don't cut the green wire..... Or was it the red?

__________________
1999 996 C2 - sold - bought back - sold for more
1997 Spec Boxster BSR #254
1979 911 SC
POC Licensed DE/TT Instructor
thstone is offline   Reply With Quote
Old 01-04-2018, 05:46 PM   #10
Registered User
 
Join Date: Dec 2017
Location: Canada
Posts: 73
Many thanks for all the replies. Black box was a 6v battery that is now out of the car. I'm guessing part of an old alarm system or IED. Didn't blow up yet anyways. It had a yellow and black wire that run towards the front of the car and looks a lot like the cruise control clutch switch wires which is just bizarre. I'll get some more work done on it this weekend and let you know what I find. As for the engine (swap, etc) that's a good point and I haven't checked to be honest! I'm going to do the 1 and 7 relay bypasses to see if cranks. Also bypassing the clutch switch.

Thanks for the post about the trunk light, I'll double check that!

I also have the service manual so I'll eventually figure it out and then do a data dump of all I've leaned about whole ignition system (DME, immobilizer, clutch switch, rfid pill, programming, etc.).
Porsche-Eh is offline   Reply With Quote
Old 01-04-2018, 06:03 PM   #11
1997 Tip, 2018 Macan
 
rexcramer's Avatar
 
Join Date: Aug 2015
Location: Upland, CA
Posts: 1,338
Garage
Be careful of the flux capacitor.
rexcramer is offline   Reply With Quote
Old 01-04-2018, 09:07 PM   #12
Registered User
 
Join Date: Dec 2017
Location: Canada
Posts: 73
Quote:
Originally Posted by rexcramer View Post
Be careful of the flux capacitor.



Couple photos of the project with and w/o hardtop. Everything works except remote buttons and it won't crank. Smells like rfid pill or previously wet immobilizer but only more diagnosis will tell. Going to get a durametric or top of the line obd reader. Thanks for the help.
Porsche-Eh is offline   Reply With Quote
Old 01-04-2018, 10:19 PM   #13
Registered User
 
Join Date: Feb 2017
Location: CO
Posts: 989
Oh man, you could have a genuine Porsche electronics nightmare on your hand. Is it possible someone tried to bypass the onboard security? Which is almost impossible. If the remotes don’t work it’s possible you have a fried immobilizer. I remember reading somewhere that the car will can go into a sleep mode, if you will, after a time. I believe it’s covered in the manual. I don’t recall the specifics. Do your keys lock and unlock the door manually? Check to see if the “little green pill” is inside the fob, or if it’s broken. The key won’t work unless the whole system can talk to each other, and the little pill in the key is the keymaster...
Geof3 is offline   Reply With Quote
Old 01-05-2018, 04:13 AM   #14
Registered User
 
Join Date: Jul 2013
Location: Bastrop, Tx
Posts: 2,643
I have one possible theory. Mice/rats love to chew on wires in the trunk. It's their second favorite spot. On top of the engine is their favorite nesting spot. Maybe a mouse/rat got up in there and chewed those wires. The owner replaced the chewed wires with that.
__________________
Woody
itsnotanova is offline   Reply With Quote
Old 01-07-2018, 10:53 AM   #15
Registered User
 
Join Date: Dec 2017
Location: Canada
Posts: 73
Quick update, car is starting and running like a champ now. I ended up buying a used set of ecu, immobilizer and key fob off eBay for $500. It was easy to swap the parts and transfer the key blade to the new fob. It is worthwhile to note the 986 and 996 share the same parts here. I'll post more later as I have lots of tips, with photos and write ups on how it to get around various starting problems. Thanks for the replies, especially the trunk light wiring one as that helped a lot.
Porsche-Eh is offline   Reply With Quote
Old 01-07-2018, 11:05 PM   #16
Registered User
 
Join Date: Feb 2017
Location: CO
Posts: 989
Glad you got it sorted! But, you haven’t answered the burning question... what the heck were all of those wires, and what were they doing, bypassing or whatever? Curious minds want to know!
Geof3 is offline   Reply With Quote
Old 01-08-2018, 04:28 AM   #17
Motorist & Coffee Drinker
 
78F350's Avatar
 
Join Date: Jul 2014
Location: Oklahoma
Posts: 3,653
Garage
Quote:
Originally Posted by itsnotanova View Post
...Maybe a mouse/rat got up in there and chewed those wires. The owner replaced the chewed wires with that.
I think Woody nailed it. The PO probably bought an inline fuse bundle to repair the harness.


Good for now, but for long term, a replacement engine harness would be best. You may be able to scrape your knuckles and install a harness with the engine in, but Probably best to wait until you are doing some more major maintenance and drop the engine. Especially if the car runs & drives well for now.
__________________
I am not an attorney, mechanic, or member of the clergy. Following any advice given in my posts is done at your own peril.
78F350 is offline   Reply With Quote
Old 01-08-2018, 08:35 AM   #18
Registered User
 
Join Date: Dec 2017
Location: Canada
Posts: 73
Quote:
Originally Posted by Geof3 View Post
Glad you got it sorted! But, you haven’t answered the burning question... what the heck were all of those wires, and what were they doing, bypassing or whatever? Curious minds want to know!
I actually don't know. Woody could be right or maybe the previous owner didn't know you need a good RFID to start and was trying to bypass something. But, it's working now and the one thing I've learned over 20 years of DIYer fixes on my cars is: if it ain't currently broken don't fix it; if you do, it will likely be broken soon

Now, as for bypassing the rfid pill I do have a good working theory on how to do it. Nothing I'm worried about a thief doing in 60 seconds as it would take more than an hour to get at all the parts. I think I'll write up a formal post and ask for feedback so this thread doesn't get hijacked.

Best.
Porsche-Eh is offline   Reply With Quote
Old 01-08-2018, 09:37 PM   #19
Registered User
 
Join Date: Jan 2016
Location: Western Australia
Posts: 94
wonder if PO was tracing a batter drain or an intermittent short circuit seeing its the red/blue cables mainly arent they power feeds?

rusty69911 is offline   Reply With Quote
Post Reply

Tags
black box 986 rear trunk


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -8. The time now is 01:35 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page