924Board.org

Tiny · Joined: 10 Apr 2006 Posts: 502 Location: London, UK

Hello everyone,

I have found the wires that go to the starter and alternator are toasted so I set about replacing them:

The trouble is, in a frenzied fit, I removed the loom that goes from the alternator/starter to the 3 pin plug by the firewall... .and now I've made the classic mistake on the starter posts... to forget which wires go where.

which one (posts 1 or 2) connects to the 3 pin plug (and then to the ballast resistor wires).

I know the configuration on the 3 pin plug is this, but but that also leaves one of the smaller wires on the starter empty. where does that go exactly?

According to this post
http://www.924board.org/viewtopic.php?t=6722 , it connects to the starter switch, but where is that located?

I dont think the wiring diagram in my haynes is for my car, because i cant see this extra wire that was on the starter?!

hope someone can help, im a dufus...and its too cold to think out there laying under the sump
thanks all
Tiny

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*****1981 - 924 - Auto - London, UK******

Smoothie · Posted: Sat Feb 16, 2008 3:09 am Post subject:

The "1?O" solenoid connection in the second pic should be post number 15a.
"2?O" should be post 50 - this one would match up with the "small post on starter" red/black wire in your third pic. (These numbers are normally formed into the black plastic surrounding the posts on the solenoid.)

Yeah, the wiring diagram shows nothing connected to 15a for '81-up.
'81-up also should have the tci-h ignition (hall effect sender in the distributor and a small black plastic "trigger" unit (aka- "Hall control unit") mounted to the wheelwell) - unless this was different for your market, or your car wound up with the earlier tci-i (inductive pickup) ignition for some other reason...

If you do have the tci-i inductive ignition (which you do apparently), refer to the '79-'80 diagrams. There, the "15a" solenoid post is labelled "16" - same post, same function (passes current only while cranking), just a different number. -And it's the one that connects to the ballast resistor.

"Starter switch" would be the thing you put your key into. Aka- "ignition switch".

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"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

Tiny · Joined: 10 Apr 2006 Posts: 502 Location: London, UK

Ahhh Great! Thanks once again Smoothie...unfortunately my problem remains exactly the same...

My battery light only switches off after the revs are raised above 2500 rpm. At that point the voltmeter shoots up into the green range.

Since then I have put on a new Alternator....all new wires to the starter and Alternator, and new V belt put on good and tight.

The only thing I've done since it was working OK is upgrade to LEDs on all my dash gauges, and ...

wire a new horn back through the steering wheel centre pad and to the correct relay. (removing the dodgy battery switch the PO put to a crappy horn)

I had to remove wires "1", and "2" (see pic) from the horn relay panel socket, as the PO had put a permanent ground where the steering pads switched ground should be.
Also there was a red/blk and green permanent live feeding to where the + that goes to the horn should be. Heres a pic showing how i found it...and ive numbered the two wires I removed and taped up.

Wonder whats happened to cause this flakey battery light prob?!

Thanks again for your help all
Tiny

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*****1981 - 924 - Auto - London, UK******

Tiny · Joined: 10 Apr 2006 Posts: 502 Location: London, UK

just a little update here,

I chased up the exciter wire circuit and cleaned up the relay panel connector pins - C2 and D2 - and the dashboard multi guage connector pin 11.

(Is it just me, but the relay plug sockets A to F, on the back are not a very tight fit...and i can pull them out quite easily.)

anyway re the battery light, when i started the car no change...it remained on....so on a whim i changed the battery bulb from the new multi-l.e.d. style one back to the old filament style one, and started the car... and one rev and it switched off and the battery began to charge - checked with DVM.

how bout that
Tiny
ps. massive thanks again to Smoothie for his excellent help and lesson on wiring diagrams. what a saviour. All hail smoothie!

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*****1981 - 924 - Auto - London, UK******

Ozzie · Posted: Mon Feb 18, 2008 9:29 pm Post subject:

The battery light has to have current going through it to excite the alt. An led would act like a blown bulb cos of the very low current it draws.
This bulb has to remain a filament type.
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Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

Tiny · Joined: 10 Apr 2006 Posts: 502 Location: London, UK

Ah gotcha thanks Ozzie. = ]
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*****1981 - 924 - Auto - London, UK******