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Old 03-09-2022, 11:33 PM   #41
cre

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If the car is cranking intermittently, the alarm system is less likely to be the culprit. Yes, relays do wear out with age and the starter relay could definitely be at fault. The clutch start switch or neutral start switch (depending on whether you have a manual or automatic transmission) is another likely source of the problem. I would start with testing these.

I would have to look at the wiring diagram for the alarm system to be certain, but I'm pretty sure the connector just needs to be unplugged so the alarm sees an open circuit and doesn't arm.. now if there is a fault in the control module it may prevent the alarms starter relay from closing. In that case, you would bypass the alarm starter relay and disconnect harness connection for the alarm module. I'm at work presently and it's going to be a late day here... I'll try to look at the wiring diagram tonight of tomorrow.
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Old 03-10-2022, 03:50 AM   #42
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Thanks CRE!

I have a manual trans. so it could be the clutch safety switch.

It just seemed curious to me that no one had mentioned the OEM—starter-relay as a likely suspect ;-)

The wire failing just seems weird ...

The wire-gauge to the solenoid at the starter is pretty beefy,
but if i read the wiring diagram correctly the current has to come through the AM1 contacts on the ignition-switch ... so ...
it seems like it shouldn't be a ton of current?

Perhaps my “easiest” first step would be to rig a temporary 14G
(or better) jumper wire from the starter solenoid (blue) wire
terminal to somewhere close to the battery and make it “safe”.
Leaving the original intact).

Then next time car does not start –
I pop the hood and touch of the wire on the positive terminal...
(with the car in neutral and parking brake applied of course… )
and see what happens….

If it starts then ... well it's not the starter or the battery.
It could still be

  1. clutch safety swtich
  2. OEM starter relay not passing adequate current
  3. blue solenoid wire crapped out
    (or high resistance connection somewhere ...)
  4. or dicked up alarm system ...
But as long as I can get home ... I can work those things out...

If I can FIND one maybe I'll just replace the starter relay because it's pretty easy...


Check the image on this page:
https://www.v11lemans.com/forums/ind...-current-draw/


Thinking about it... installing a "helper" relay really addresses both #2 and #3 at the same time... without isolating the actual cause...?


Looking at the alarm:
http://www.cygnusx1.net/Supra/Librar...ection=BE&P=85



The hood switch is just a switch to ground and shown in the "open" position ... which I think means it would close when you pop the hood and I can just unplug it and defeat the alarm?





I think my brain is full... time for a beer.


AGAIN thanks for your help!
Any further thoughts much appreciated!
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Old 03-10-2022, 05:05 AM   #43
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Well... I just went out and pulled the relay out of the passenger kick panel...
Then popped the plastic cover off of the relay ...
Thankfully it wasn't a crimped metal case...

The relay contacts look fine ... essentially like new
However there was a bit of corrosion on the four spade lugs,
and they didn't seem to be all that tight in the mating connectors...

I don't really think the relay is the issue but maybe... ?
Tomorrow morning...I will gently tighten up the female crimp connectors just a bit
with some needle nose pliers(battery disconnected of course

Plug the little green bastard back in and see what happens...
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Old 03-10-2022, 08:43 PM   #44
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Well:


crap came up this morning...


I went out just now sprayed some contact cleaner on the contacts just for good luck, blew it off with compressed air snapped the cover back on.


I DISCONNECTED THE BATTERY



Took a small flat bladed screw driver and tried to add a little tension to the female spade clips on the panel. The way it was oriented I could only get to one side easily but I did the best I could.


I put some dielectric/bulb grease on the contacts and snapped it ...

It went in with "vigor".


Reconnected the battery ... started right up!


Is it fixed? BTFOM....
I'll report back in a while with long-term results.


Kudos and beer money to cre
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