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Bad Ignition switch? (late car)

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Old 12-05-2021 | 07:39 PM
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From: Rocky mtn High
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Ok just did a voltage test, the starter wire is showing 0.7v....
Still hearing that "double click" which I thought was the starter solenoid, but clearly couldn't be now, maybe some other relay.


Old 12-05-2021 | 08:45 PM
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Looking at the schematic, the starter current goes from the ignition switch on a fat red with black stripe wire, to the central electric box. Then out of the central electric box on a fat red with black stripe wire to a connector (labeled T24 on this diagram) and continues on a fat red with black stripe wire to the solenoid. 'Fat' is relative to other wiring harness wires, not like the battery and alternator cables. There is no relay in the path between the switch and the solenoid. The connector is a potential suspect, but I don't know where it is exactly. It looks like a smaller black wire from the alternator passes through the same (2-pin) connector, it might be easier to find the connector by tracing from the alternator end.



Start circuit late 944
Old 12-05-2021 | 09:41 PM
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Actually one thing I wonder if could be a contributing factor, is that just prior to this, I pulled off the alternator and swapped the Voltage regulator.
Old 12-06-2021 | 02:31 AM
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Its got to be something else, The starter works, I'm sure its not the ignition switch, the wires look good. WTF??? Could it have anything to do with the alarm?
I mean it worked fine until it didn't, never had issues before.
Old 12-06-2021 | 02:36 AM
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Problem with the wiring diagram is that it doesn't show me where it is on the car, and with them being bundled, makes it very hard to examine.
Where is the central electrics box? or do you mean the fuse box?
Could it be DME related at all?
Old 12-06-2021 | 03:21 AM
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I just check and I am getting 12v at the ignition switch.
Old 12-06-2021 | 11:52 AM
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Are you getting 12V at the starter from the ignition switch wire?
Old 12-06-2021 | 12:12 PM
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Yes, the central electric box is the fuse box.
Old 12-06-2021 | 02:06 PM
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Originally Posted by michael7810
Are you getting 12V at the starter from the ignition switch wire?
Im getting 0.7v at the starter
Old 12-06-2021 | 02:41 PM
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Disconnect the fat red wire with black stripe at the ignition switch and at the starter. Test continuity.
Old 12-07-2021 | 07:04 PM
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Well, I got it started! not %100 sure how. I tested continuity and got none. Traced the wires in the engine bay and saw nothing. So I wedged my self under the dash as took off the cover for the bundle of wires (which was a pain) I Couldnt see anything obvious, as A. its a rats nest and B. All the wires are bundled with tape from the factory.... :-{ Doesnt look like anyone has ever touched them.
So, last try I just pushed up on the wires and kind a rocked them back and forth. They are fairly stiff I don't see how there could be anything broken or come loose.
the only other thing I did was pull off the door chime? under the dash (which sounded like a faint clock ticking, I didnt know what it was until I pulled it out) but I doubt that had anything to do with it.

I gave up, but said what the heck, one last crank attempt and it worked!
But now the question is, what and why? and what fuse/relay does that wire go through? (I can't tell on the diagram)
Old 12-07-2021 | 08:26 PM
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the 968 diagrams show a two pin connector (T24) for the starter lead (4.0 re/bk) and alt lead (1.0 bl) that conflicts with the diagram above.



Last edited by thomasmryan; 12-08-2021 at 01:52 PM.
Old 12-08-2021 | 06:53 AM
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Oxidized contacts at T24 (wherever it is) would explain the symptoms. I'd find it and clean it (even if it's working now, if there's lots of oxidation it might not stay working).

Last edited by jeyjey; 12-08-2021 at 10:28 AM.
Old 12-08-2021 | 10:02 AM
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Detoxit F5 is a good contact cleaner.

A volt - ohm meter doesn't really give an insight to the current capacity of the circuit.. A single strand of copper might still show B+ but not allow enough current to engage solenoid or relay.
Old 12-08-2021 | 11:21 AM
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It might be easier to run a new 14 or 16 ga wire (size dia. determined by equivalent metric to GA conversion) from ignition switch to starter solenoid than try and find the suspect connector.

Last edited by T&T Racing; 12-08-2021 at 11:23 AM.


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