Power Window/Power Seat Circuits Crossed?

[cabmandone]

Originally Posted by Smoove1010

Today's progress report:
- Having firmly established that it was spliced to the fuel pump wire, and thereby a direct-connection to the fuel pump, I re-positioned the red wire from the top of fuse 8 to the bottom of fuse 3. Turned key to the ON position: fuel pump did not turn on... so far, so good. Turned key to start, the car lit right up and ran! The fuel pump is now operating when, and only when it's supposed to.

- Having studied numerous iterations of schematics, and having convinced myself that the red and red/blu wires were not supposed to cross in the "baffling" J-connector pictured above, I pulled the red/blue wires out of the J-connector and connected them directly to each other. Windows no longer worked with the car off and key out; Turn key on, windows work; Turn key off, they work until the door is opened. Mission Accomplished!

A battery drain was the initial impetus for this mission, so to insure that I achieved what I set out to do, I put the ammeter in series with the battery negative terminal and the car's ground cable - parasitic draw is down to 40-50 milliamps. (It wavers between the two once every second, so I'm assuming that's the clock ticking.) When the power window relay was continuously energized the draw was closer to 100 mA.

My conclusions are:
- The fuel pump was probably powered by a bypass circuit as the old DME and/or old DME relay was failing. I'll have to test the old relay to see if that theory holds water. If it does, I'll have to discard the old relay which I had kept as an emergency spare;

- There are signs that a wiring harness from another car was at some point grafted into the car. I suspect that the person who did the grafting made an error in joining the red and red/blu wires in the j-connector thereby crossing the circuits and creating the power-window-relay battery-drain.

Now all I've got to do is finalize the new/restored wiring configuration with some better connectors, shrink-wrap and sheathing. I'd also like to tidy up that nest of wiring around the fuel-tank filler neck.

So while the solutions to these problems amounted to little more than restoring the connections to their rightful places, I couldn't have done so without the help of the brother Pelicans who responded to this thread. Thanks to your wisdom and patience I resolved my issues and learned a good deal more about my car in the process. I'm grateful for your assistance. I'll be applying some of this new-found knowledge to solving a few more wiring-related riddles in that frunk...

Best Regards,
GK

Sweeeeeeeeeet! Glad you got it resolved.

[scarceller]

So the battery drain was the windows always being powered and the FP issue was simply something dumb done by a PO.

As for a bad FP relay, if you have a bad one you can easily create a super heavy duty one by gutting it then soldering up harnesses to 2 40AMP standard square relays. I have my relay done this way and it never heats up and most likely will last forever. And if it goes bad it's easy simple replacement with a standard 40Amp relay. If you want details let me know.

[Smoove1010]

Originally Posted by scarceller

So the battery drain was the windows always being powered and the FP issue was simply something dumb done by a PO.

As for a bad FP relay, if you have a bad one you can easily create a super heavy duty one by gutting it then soldering up harnesses to 2 40AMP standard square relays. I have my relay done this way and it never heats up and most likely will last forever. And if it goes bad it's easy simple replacement with a standard 40Amp relay. If you want details let me know.

Yes, that is the long and the short of it. Your relay-on-steroids sounds like a great topic for a post on this forum!

Thanks Sal,
GK

[scarceller]

Originally Posted by Smoove1010

Yes, that is the long and the short of it. Your relay-on-steroids sounds like a great topic for a post on this forum!

Thanks Sal,
GK

If I get some time I'll take pictures of the altered relay and share the wiring schematic. Reason I created this super hi-amp relay option is that I piggy-back extra hardware onto the DME and the stock relay would not hold up. If you are curious see this thread:

Wide Band O2 + data logger for 84-89 Carrera

[westcoast911]

Hello all,

I'm having the same problem with my 88 coupe. With relays removed, windows and sunroof stay energized. With the #1 fuse removed, windows stay energized. With #2 fuse removed, windows stop working.

Smoove1010, I was wondering what the location of the odd connector that tied all the wires together was and if that may be a way to solve my issue as well? In your pictures it appears to be close to the brake booster mount, but I see no such connector on my car.

Thanks for any help with this odd problem I have spent years living with!!

[Smoove1010]

westcoast911 -
Take a look at this pic from early in the thread:

The J-Connector, which in my car's case was apparently incorrectly applied, was under the part of the wiring harness that's obscured by the fuel filler neck. It's at the 6 o'clock position in this picture just left of that blue crimp connector. You might need to dig a little to get to it IF that's your culprit.

My advice - do the most basic thing first - make sure your interior light plunger switches are operating correctly. This seems to solve most problems of this type. They didn't in my case because somebody molested the wiring in my car. Bless those PO's and their wrenches...

GK