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Starter won’t crank (unless I trick it)


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Hello,

Before you say"battery" it ain't dead. Twisting the key does absolutely nothing, everything works, just doesn't crank at all.

However, If I take the relay in the trunk out, jump the fat (YE & YE/BK) wire leads, twist the key and the starter cranks away but the motor won’t start. The two leads to that activate the relay show no voltage when the key is twisted.

I had and identical problem when the computer under the seat got swamped (since been replaced) Took it out, opened it up and it looks fine. So does the starter relay (It's just not getting V. to it). And of course checked the fuse, fine. I always a make a point of pulling electrical connections on and off a couple of times to assure a good connection.

The obvious choice is the ignition switch. But again, when I jump the starter relay, it will crank when I twist the key. According to my wiring diagram there is only one lead that is activated when the key is twisted to start. ALSO, the clutch switch is jumped, not an issue.

This has been an intermittent problem while I've had the car up for mods. (nothing that is related to this circuitry that I know of).

Ideas??

PK

Edited by pk2
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And you have checked the clutch interlock switch?

Yes try what Loren suggested. MY99 had the same problem Friday morning. Key turns, dash lights all on, electrical system works but car would not start. So tonite I checked the clutch switch & the car started. Check it out, depress the clutch and pull out the switch with your fingers. I need to clean the switch now.

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Hello,

Before you say"battery" it ain't dead. Twisting the key does absolutely nothing, everything works, just doesn't crank at all.

However, If I take the relay in the trunk out,...the key is twisted to start. ALSO, the clutch switch is jumped, not an issue.

This has been an intermittent problem while I've had the car up for mods. (nothing that is related to this circuitry that I know of).

Ideas??

PK

Fixed It !!!! (Not really sure how though)

Poured over the wiring diagrams for hours, figure out where there should be voltages, weren’t there. Made some jumps here and there, got the voltages…still wouldn’t start.

Checked all the grounds, O.K. Id had the Motronic computer thing out (checking pin assignments for sc install) couple days before, looked like I’d put it back correctly, took it back out anyway & opened it up, solid state, nothing to do in there but damage.

Cleaned all the pins with a wire brush. Plugged the harness connector in and out a few times (helps insure good contacts). Buttoned everything in good. Twisted the key, resigned to the silence I’d heard so much of today…Vaarroooom!!!

PK

Such pros, not Hemingway but…

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Hello,

Before you say"battery" it ain't dead. Twisting the key does absolutely nothing, everything works, just doesn't crank at all.

However, If I take the relay in the trunk out,...the key is twisted to start. ALSO, the clutch switch is jumped, not an issue.

This has been an intermittent problem while I've had the car up for mods. (nothing that is related to this circuitry that I know of).

Ideas??

PK

Fixed It !!!! (Not really sure how though)

Poured over the wiring diagrams for hours, figure out where there should be voltages, weren’t there. Made some jumps here and there, got the voltages…still wouldn’t start.

Checked all the grounds, O.K. Id had the Motronic computer thing out (checking pin assignments for sc install) couple days before, looked like I’d put it back correctly, took it back out anyway & opened it up, solid state, nothing to do in there but damage.

Cleaned all the pins with a wire brush. Plugged the harness connector in and out a few times (helps insure good contacts). Buttoned everything in good. Twisted the key, resigned to the silence I’d heard so much of today…Vaarroooom!!!

PK

Such pros, not Hemingway but…

Nothing, no matter how well crafted, beats the sweet sound of success!

I admire your perseverance!

Regards, Maurice.

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  • 2 months later...
And you have checked the clutch interlock switch?

Yes try what Loren suggested. MY99 had the same problem Friday morning. Key turns, dash lights all on, electrical system works but car would not start. So tonite I checked the clutch switch & the car started. Check it out, depress the clutch and pull out the switch with your fingers. I need to clean the switch now.

i have a 2000 S and i am experiencing the same problem. can you tell me where is the clutch interlock switch?

thank you.

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  • Admin
And you have checked the clutch interlock switch?

Yes try what Loren suggested. MY99 had the same problem Friday morning. Key turns, dash lights all on, electrical system works but car would not start. So tonite I checked the clutch switch & the car started. Check it out, depress the clutch and pull out the switch with your fingers. I need to clean the switch now.

i have a 2000 S and i am experiencing the same problem. can you tell me where is the clutch interlock switch?

thank you.

The clutch interlock switch is on the clutch pedal. As I recall it looks like a gray plunger. If you connect the two wire from the switch then you bypass it - just be careful that the clutch is depressed or your are in neutral.
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Hmm... I have seen at least one DME where the connector was not tight and the connector was at best half-on.

So, let's hope that was it.

Loren,

Ya, I don’t recall it’s state (plug wise) when I took it (the Motronic) back out again. But, I spent my formative years as the family mechanic for dad’s ever revolving piece of sh@# fleet. I went on to resurrect about 25 of my own by the of by the time I was 25, in part paying for college and in part to drive cool cars I could otherwise never afford.

For that reason, I find it hard to believe (or admit) I could have put it back together radically catawampus, but, as you said...So here we are though, 3 months later, humming away without prolems.

Regards,

PK

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PK,

I think your solution lies in

"had an identical problem when the computer under the seat got swamped (since been replaced)"

did you mean the box got soaked with water? Even if the computer was replaced corrosion can build up in the connector. The act of removing the connector and reinstalling it could have cleaned up the pins.

Edited by Danyol
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PK,

I think your solution lies in

"had an identical problem when the computer under the seat got swamped (since been replaced)"

did you mean the box got soaked with water? Even if the computer was replaced corrosion can build up in the connector. The act of removing the connector and reinstalling it could have cleaned up the pins.

Thanks,

This true and I’m pretty vigilant about this sort of thing as you will see. Not sure how this post got resurrected. It was back in October I had the problem.

Go here (in this thread ) for solution, still running strong…but with a supercharger no less.

http://www.renntech.org/forums/index.php?s...rt=0#entry83533

Thanks for for the though,

PK

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  • 3 weeks later...
And you have checked the clutch interlock switch?

Yes try what Loren suggested. MY99 had the same problem Friday morning. Key turns, dash lights all on, electrical system works but car would not start. So tonite I checked the clutch switch & the car started. Check it out, depress the clutch and pull out the switch with your fingers. I need to clean the switch now.

i have a 2000 S and i am experiencing the same problem. can you tell me where is the clutch interlock switch?

thank you.

The clutch interlock switch is on the clutch pedal. As I recall it looks like a gray plunger. If you connect the two wire from the switch then you bypass it - just be careful that the clutch is depressed or your are in neutral.

ok guys, i am totally lost. i got down and looked around the clutch, and the only part that i can remove is i believe the clutch cruise control switch. its got a push switch at one end on the clutch padel side and the red cruise control connects to the other end. i do see a steel plate with two wires connected to it. is that the clutch interlock switch? if it is, it can not be removed and cleaned like what walt2810 said.

i am not sure if my problem is the clutch interlock switch. even though i have exactly the sympton, but if i turn the key and hold it for 5 to 10 seconds, it will start. but it is getting worse. last few days, i have to try 4 or 5 times each time turn, hold it, take the key out and put it back in and repeat for the car to start. can this be something else? please help a 2000 s.

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I can say Ditto! No idea what is causing it, but I can turn the key, see the lights and no cracking or firing. No water on the floor and relays look good. grrr.

Wish I can remember what tiped the scale but it was probably a “duh” head slapper.

Regards, Pk

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