924Board.org

[CBass]

After doing a clutch job on my car, I ran into a no start problem, it wouldn't crank. Checked the started, one of the solenoid contacts was broken inside the housing, so I replaced the starter.

Now when I try to start, I get a rapid engagement of the solenoid, CLACKCLACKCLACKCLACKCLACK, and the occasional whisp of smoke that I can't hunt down in the engine bay. The solenoid problem seems to be related to a pair of wires, a red/yellow wire and a brown/white wire. I have no idea where these wires go, but when the brown/white wire is groundged to the engine, I get the solenoid going crazy like that.

It started fine before the clutch job, although I did move the fuse block around and I think that might be part of it as well.

Does anyone know what these wires are supposed to do, offhand? I can't find them anywhere in the wiring diagrams, and they do look to be original...
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'81 931 in various states of assembly

[CBass]

bump

Still poring over diagrams, anyone have any input?
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'81 931 in various states of assembly

[Gram]

I can find a br/wh at the headlight dimmer switch for a '76/77 car, and a re/ye at the fan relay circuit on a '79 car but that isn't going to help you ..sorry.
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'82 924 NA Euro (hers)
'98 Audi A4 TDI (ours)

[Ozzie]

Those colors don't come up on any of my diagrams for the starter.
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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

[Paul]

You did connect the ground wire from the coil mount to the block, correct?

[CBass]

[Ozzie]

The black with red stripe is Term 50 from the ign switch to the starter, fuel pump relay and CSV.
If disconnected (mine is to protect ign switch) it should go to a relay to provide power to those items.
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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

[CBass]

Hmm, the black wire with red stripe has a female spade connector on the end, with a flexible cover. I can't find anything handy for it to plug into, the only thing it reaches are the nearest "G" spades.

Other thing that though, I have found a pair of red wires with 4 black stripes, 10 guage I think, that bridge into a female spade terminal with a rigid plastic cover on it.

I get the impression I'm in a little over my head here...
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'81 931 in various states of assembly

[CBass]

Was doing some googling and found this article, short but somewhat helpful. Info on understanding DIN wiring diagrams

http://www.findarticles.com/p/articles/mi_qa3828/is_200304/ai_n9171875

So the 50 source is powered when cranking and when the ignition switch is in the "on/engine running" position, correct?
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'81 931 in various states of assembly

[Ozzie]

Source 30 (i think) goes to the ign switch.
The ign switch supplies the power to the 50 source, for crank etc.
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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

[Smoothie]

50 should only be powered while the ignition switch is in the start position.
Look at the top of the wiring diagrams - you'll see 5 horizontal lines: 30, 15, X, 31, 50....
30 = 12V+ always
15 = 12V+ at ignition on and also when starter's activated
X = 12V+ at ignition on, but not while starter's activated
31 = a ground
50 = 12V+ only when starter's activated

Don't go plugging in loose wires under there without knowing where they go or if they're needed. I have a couple unconnected - a gn/re and a re/bk. They're for assorted features like foglights, headlight washers, whatever, that weren't installed on the car.
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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

[CBass]

Awesome, thanks for the info, guys. I guess I'll have to start playing with a multimeter and see what I can find...

I have yet to go from one end of the circuit to the other with a multimeter, guess that's tomorrow's job.

Thanks for all the replies!
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'81 931 in various states of assembly

[CBass]

Ok, checked out the three post connector 3a that connects the 50 and 16 circuits to the starter, I'm getting 9 volts at the 50 wire on teh connector itself, is that enough to kick over the solenoid?

I'm getting 3.7 volts at the coil's 15 connection with the key in the "on" position, although this drops to 3.4 when I crank it.

I assume this points to a really bad connection somewhere.

I tested it by grounding the multimeter to the ground strap and digging the positive meter cable into the backside of the terminal, so I assume it had had a good connection there.

For some reason, teh rapid engagement of the solenoid has stopped today.

Any thoughts?
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'81 931 in various states of assembly

[Smoothie]

Verify that your battery voltage is over 12V - also check it with the ignition switched to start.
Then you could look at (and check voltage at) terminal 50 of the ignition switch, then check E17 for burning/corrosion (the 5th connector from the left (as facing forward) on the back of the fuse-relay board, pin #17), then check A10 (1st connector, pin #10).

If the battery's good, you might just need a new ignition switch. Then again those whisps of smoke have to leave you wondering. Wiring near the starter maybe damaged during clutch work?
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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

[CBass]