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Technical data needed - Please post full ground points and wiring schematic for SC400

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Old 02-21-07, 05:21 PM
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CLRH2O
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Default Technical data needed - Please post full ground points and wiring schematic for SC400

So I've searched and I've searched and the very closest I've found is a single comment by one user *within* an only partially related topic thread that mentions but two of the who knows how many grounding points on the early model SC400 electrical system. (specifically they mention the chassis to block point on the drivers side)

Can some one please post full ground points and wiring schematic for SC400.

I ask because I have to go check these points by what seems like an endless string of replies from O.L.T. to other members who's clocks are resetting themselves of who's engine has trouble starting / turning over even though their batteries are brand new, their battery cables are sparkling clean and their alternators have checked out as A-Ok. (just as mine all have).

Any help would be EXTREMELY appreciated!
Old 02-21-07, 05:55 PM
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over40driv
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Sounds to me like your starter may be dead.
Old 02-21-07, 06:45 PM
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O. L. T.
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You're spinning your wheels looking for *all* the ground points because they are too small to have an effect on the main system. Only the main grounds affect the system in a dramatic way. (block, chassis, battery)

There are over 12 grounds to frame in the dash alone, are you planning on removing your dash to check all of those? Of course not. They ground to the tube dash frame, guess where the dash frame grounds to......
Old 02-21-07, 07:06 PM
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CLRH2O
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Ok, so main grounds are all you need to focus on first. I'm fine with that.

That said and known, where are they located and is there a schematic for them available that can be shown here by chance?

Also, would the issue with my car being so hard to start have any correlation with the fact that my clock is constantly resetting it's self to 1:00 and I lose my tripometer numbers? Being all electrical I'd have to assume so in at least some way. Additionally what is the procedure for testing the starter on a 1993 SC400? Can it be even be checked (let alone fixed or replaced) without spending 800 dollars in engine tear down labor time?

Input?

I'd like to stay mostly on topic about the NEGATIVE GROUND POINTS / ELECTRICAL SCHEMATICS for the most part - but any input related to the starter in ways that might also pertain to that main topic is good info as well.
Old 09-14-08, 11:38 AM
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JonSC4
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Has anyone gotten a hold of a ground point diagram? I would like to redo my main grounds before I put a new stereo in.
Old 10-03-08, 04:09 PM
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boobstar
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I would also like to know
Old 10-03-08, 08:24 PM
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Curry
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The first one goes from the battery to the chassis. Its probably the easiest one to find. Trace the thick black wire from your negative terminal down and you'll see that it ends up on the chassis. There's you're first ground.

Can't help you with the other two because I can't remember where I found them when I pulled my motor.
Old 09-10-09, 04:35 PM
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BrownGuy
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Before starting a new thread I just wanted to know if there is any update on the MAIN ground schematic, pic, etc?
Old 09-10-09, 09:08 PM
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KC95SC400
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I have the schematic that shows all ground points, splice locations, connector locations.........but it is too big of a file to upload.

I can email it out if it's really needed.

KC
Old 09-11-09, 03:45 AM
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Anti-Venom
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Hope this helps.





Old 08-11-16, 02:45 PM
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TyStephens
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Originally Posted by Anti-Venom
Hope this helps.





Hey could you repost those photos? They are now MIA and I cannot for the life of me find the grounds attached to the heads.
Old 07-31-21, 11:00 AM
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400Tone
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Originally Posted by KC95SC400
I have the schematic that shows all ground points, splice locations, connector locations.........but it is too big of a file to upload.

I can email it out if it's really needed.

KC
If you can send the file to my email I’d appreciate it
Old 07-31-21, 12:28 PM
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RXRodger
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Originally Posted by 400Tone
If you can send the file to my email I’d appreciate it
Being that post was made 12 years ago I am going to guess that dude is long gone from here.
Old 09-30-22, 02:46 PM
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Last edited by HmRekr; 09-30-22 at 02:48 PM. Reason: Clean up
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