924Board.org

[1980-924]

924 NA won't start, checked the web and most seemed to indicate that a sudden failure like that was due to a cracked electrical portion of the the ignition switch. Disassembled steering column and the plastic part of the switch did have a crack in it.
Replaced ignition switch and the starter still won't engage.
So I have the starter out and testing appears to show that the current is not getting to the solenoid to engage the starter. Which of the wires on the solenoid actually engages the starter - the one of the top (painted red) or the one on the bottom?
Here's the solenoid/starter:


I checked the switch and it was good, I jumped 30 to 15 and 30 to 50 on the plug that connects to the ignition switch and the starter still does not engage.
I checked the wires from the starter to the plug here and they are good:


So which of these 3 connectors in this plug gets the current when the ignition is on and which of these get current when the key is supposed to engage the starter? The top left or the top right?


I'm thinking I have a break between this connector and the plug for the ignition switch or is there another component that could be causing the problem?

Also - I'm missing one of the caps that looks like a wire nut from the center of the tachometer, anyone know where I can get a replacement?


Thanks in advance!!!

[scm924s]

Check all the wiring between plug and starter/alternator, this length of harness gets cooked by the exhaust, and many problems occur as a result.
_________________
1984 n/a Ruby Red Metallic
1988 924S Guards red- sold
1986 924S Guards Red - sold
1984 n/a Black - sold
1980 n/a Le Mans#1 - sold
1980 n/a Le Mans#2- sold
1977 Martini - sold

[1980-924]

Yes - I checked the three wires from the starter to the plug. They appear to be fine.
The problem appears to be between the ignition switch and the wire that is to send the signal to engage the starter.
Is there a diagram that labels which is which in the three wires in the plug and which is which of the two wires on the solenoid?

[scm924s]

try hhttp://www.pelicanparts.com/944/electrical/944_electrical_diagrams.htmere
_________________
1984 n/a Ruby Red Metallic
1988 924S Guards red- sold
1986 924S Guards Red - sold
1984 n/a Black - sold
1980 n/a Le Mans#1 - sold
1980 n/a Le Mans#2- sold
1977 Martini - sold

[Ozzie]

or buy a Haynes manual
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

[1980-924]

So, which of these is the Ignition Switch?
A is the Battery and B is the Starter and - where is the 3 wire connector located on this image that I included a picture of in my original post?



I have the Haynes Manual and looking at Page 269 - Fig. 11.17 Current flow diagram for automatic transmission - D is the Ignition Switch and shows 50 and 15 there - B is the Starter (and Solenoid?) and it shows only 50 there along with the ground. There are 2 wires on the Solenoid along with 2 wires for the 12volt - 1 to the Battery and 1 to the Alternator. Where in the Haynes manual (page number - figure number) do they show what I am asking about?






My first question, in 3 parts, was can anyone identify the;
1) Wire Number of the top left wire in the 3 wire connector
2) Wire Number of the top right wire in the 3 wire connector
3) Wire Number of the bottom wire in the 3 wire connector



My second question was can anyone identify a source or provide a part number for the cap that looks like a wire nut from the center of the tachometer - as shown in the following picture:
[/img][/b]

[!tom]

The 3-wire connector is in the diagram as T3. The conductors are numbered T31, T32 and T33.

What year is your car? A 1980? The current flow diagram for the starter that you posted is on page 258 for the 1979/1980 years, and it shows the T3 connector. Page 269 has the automatic transmission specific parts.
_________________
78 924 NA
5-lug

[1980-924]

I don't speak - schematic - so seeing a single connector spread over several inches on the page doesn't make sense.
If there are 3 wires physically right next to each other in 1 connector as in the picture - I expected to see them in the same location in the diagram.

My original question -
So which of these 3 connectors in this plug gets the current when the ignition is on and which of these get current when the key is turned to "Start" is supposed to engage the starter? The top left or the top right?



So, which of the 3 wires - numbered T31, T32 and T33 is:

1) The top left connector?
2) The top right connector?
3) The bottom connector?

[larchie]

>> Which of the wires on the solenoid actually engages the starter - the one of the top (painted red) or the one on the bottom <<

The top wire in the Image should be Red/Black and comes from the Ignition Switch.
The bottom wire should be Black and goes to the Ignition Coil.
So neither of these wires engage the Starter.

The starter motor connector terminal is the field winding connecting strap (silver braid-like) at the bottom of the solenoid inserting itself into the starter motor.
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Turning the ignition switch to On Position closes the ignition circuit. Turning the ignition switch further to the Start Position closes the circuit and both of the following occur:

(1) current from Positive Terminal of Battery by means of Diagram's Black Wire 16 flows through Connector 30 to Solenoid and

(2) current from Ignition Switch to Diagram's Red/Black Striped Wire 40 flows through Connector 50 relay to Solenoid.

(1) and (2) cause current to flow to Starter Motor through the field-winding connecting strap.
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>> Is there a diagram that labels which is which in the three wires in the plug and which is which of the two wires on the solenoid? <<

The 3 Pole Terminal Connector according to the Porsche Workshop Manual Wiring Diagram for a 1980 924 show ...

(1) Generator Regulator Black Wire 10 goes through T3 connector to Brown Wire 05 to Instrument Cluster
(2) Red/Black Striped Wire 40 goes through T3 connector to Red/Black 40 to Ignition Switch AND Red/Black 10 to Cold Start Valve and Thermo Switch. This is the ON Circuit.
(3) Black Wire 15 goes through T3 connector to Red Wire 10 to Ignition Coil.

(In the Start Position of Ignition Switch of course all three poles have current flowing.)

So it looks like in your picture the three-pole Terminal 3 does not match the Porsche Official Workshop Manual. Since there aren't any other three pole terminals in the engine compartment for the 1980 924, if I were to guess, the aqua and pink appearing colored wires in your Image of Terminal 3 would be going to the ignition switch and thermo switch (the latter being green/white in the Porsche Manual).
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My guess is the solenoid is shot -- maybe take the unit to an Auto-Parts for testing.

Some things to try:
(1) To test for a short with everything connected, turn off everything electrical, disconnect and clean the end of your battery ground strap and then hold the cable close to the ground post. If you see a spark, you have a short.

(2) If you heard a click after turning the key to the Start Position, then you might try hitting the starter (not the solenoid!) with a rubber or wooden mallet. (Also, if the motor were installed in the car, sometimes rocking the car in gear will likewise dislodge the pinion gear from the flywheel teeth.)

(3) If you can reconnect the Solenoid/Starter while removed and hold it in place, short across the Solenoid's battery connection and the wire to the starter motor (I.e., this results in a direct connection from the battery to the starter motor across the two main terminals with the large nuts stacked vertically in your Image)-- if the motor doesn't whirl, then it's shot.

(4) With everything connected, engine off, short across the terminal from the battery connection on Solenoid (large one at the top) and the small terminal with the Red/Black stripe wire which goes to the ignition switch. If the motor whirls, then the trouble lies either with a "bad out of the box" ignition switch or the Solenoid. You can try tapping lightly the solenoid just in case the insides are binding from rust or decay.
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>> I'm missing one of the caps that looks like a wire nut from the center of the tachometer, anyone know where I can get a replacement? <<
Looks like a VDO Drive Key for Tacometer (possibly part # 340 061 ?)-- most likely available from VDO here:
http://www.vdo-instruments.com/service-parts.html
but better call to make of size.

[1980-924]

Thank you for the diagnostic steps... I have them saved and I an sure they will be most helpful.

I had the starter down to Advance Auto and had them test it and the starter did spin up with no problem. After I had it home and hooked it up it did not engage / spin / anything - sounds like the wiring, right?

I actually ran into an old friend who is a GM Master mechanic and discussed the problem - he suggested the tap with a hammer on the starter as it may have had 'stuck brushes' - damn - that did it - I tapped it twice, hit the switch and it spun right up.

I'll be ordering a new starter along with the other parts I need.

Thanks again for a well thought out and informative response!!!

[larchie]

Why not rebuild or have your starter rebuilt if you have a local rebuild shop?