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Discussion Starter #1
MK II Celica Supra 86

I decided to change the badly malformed terminals. When I hooked everything back up (the main +/- leads, as well as the other two wires on the + side and the ground wire on the - side), the car will not crank. The only noise I hear is a single hard click from what I assume is the starter. All electronics work fine. I noticed that the negative terminal is considerably more worn than the positive terminal. I used the fitter that came with the terminals, but it doesn't seem to fit right (there are sizable gaps) because the negative terminal is sort of deformed, likely because I would slip it on and off while working on the car to disengage the battery. I always removed the negative terminal first and reconnected it last.

Is it possible that something else went wrong? Can I just shave the post on the battery so that I can fit things more snugly, or should I get a post cap?
 

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Check your fuseable link and make sure its not toast.
Also double check to make sure you have 12v and verify all your wires are on the terminals as they should be. just go back through everything you did and make sure its correct!!!

Report back with what you find.
 

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The starter circuit takes a LOT of amps to engage. Terminals must be clean and tight. NO post cap. Get a real cable, not a cable end.
The entire car depends on a good grounds. Did you do the BIG THREE?

I agree with the above post. (y)
 

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Discussion Starter #4
I'll try those out. The vehicle has not had any major modification done to the electrical work as far as I can tell.

What are the other two wires that hang off the positive terminal? One of them has a really thin gauge.
 

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Probably added by the PO. Maybe a volt meter or the like. Should be 14-16 G.
 

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Discussion Starter #6
I will get a photograph when it is brighter outside.

As for the original issue, I got a lead post cap and jammed it on the negative terminal. I tightened the cable terminal as much as I could to make sure there are no gaps. Car cranked and eventually started. I am not buying steel cable terminals again.
 

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Buy a REAL cable- FAT as possible, of the correct length.
 

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Discussion Starter #8
What do you define as a real cable? I am fairly sure it is the original one. Do you mean a cable with a soldered end? I don't see why that is necessary. My 2011 Honda CR-V has stock crimped terminals that run fine. It just seems more difficult to deal with when they eventually break.
 

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One piece cable with copper wire inside. Crimped and soldered will do. Auto parts store has them. Your CRV take MUCH less current to run the starter than your Supra. CRV probably has 10 gauge copper wire. I use 6 gauge wire to the starter.(2) 8 G. wires from the alternator and 8 gauge wire for ground to the firewall. The big THREE.
How to Upgrade the Big Three (the12volt.com)
 

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Discussion Starter #10
I will research this.

I will admit it is somewhat confusing because you are talking about the gauge, rather than the type of cable terminal as it pertains to the functionality of the vehicle. I will check the gauge of the cables tomorrow. The car does have some oddities, though I always assumed those were local issues rather than an overall problems relating to the vehicle not getting enough charge from the battery.
 

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When any car manufacturer makes their cars they went cheap on COPPER cables. They still do.
Our cars have marginal alternators and WIRE to save manufacturing costs. Smaller wires can carry less current than FAT wires.
When people install big tunes, 2 G. wire is used. If they run an electric fan etc, they will upgrade the alternator and use fatter gauge wire. Crimped, not soldered. The big three.

You will get into the oddities of your car, eventually. Multiple complicated systems and we know them well. ;)
 

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Discussion Starter #12
The cranking issue was resolved, and the car now starts. The contact for the terminal end was bad. After tightening the connections, the car eventually started and drove around with no problems.

However, the discharge warning for the battery came on the next day. I tightened the connections, but this did not do anything. I used a voltmeter to check if the battery does actually discharge, which it was (only 11.84 when running). I finally decided to check the connection for the terminals and found that the contact screw for the main positive lead was actually digging into the insulation instead of the copper. I fixed this, but the battery still discharges.

I took the battery to O'Reilly's, and charged+tested in there, but they said it was fine.

I will also add that the blue cable in the attached photo actually disintegrated when I was retightening things, and ended up replacing it completely because there was no saving it. I have no idea what either of those two smaller cables do, perhaps they are for the headlight retracter motor and a volt meter. I am not sure if they have anything to do with the discharge issue.

My next guess is that the alternator is bad, but I have not had any issues with it. It was fine before and there are no issues with the electronics working. I would prefer not to change it.

The car does sit a lot, and gets driven maybe once a week.

What could be the issue? Should I just swap the alternator?
 

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The blue fusible link wire is the most important wire in the system, it powers everything. Needs to be replaced with a 2.0 fusible link wire or risk a car fire.
Yellow fusible link 1.0 powers ignition switch, lighting, rear defroster ,sunroof, windows etc.
The following needs to be checked for alternator to work. Fusible link 1.0 Y in engine fuse box(signal wire for alt).
15 amp engine fuse (powers IC regulator in alt)
7.5 amp ignition fuse and 7.5 amp charge fuse for charge warning light, yours work since the charge light came on.
 

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Discussion Starter #14 (Edited)
Does the fusible link box need to be rebuilt in a certain way? Is there an example of how it SHOULD look? Is there any difference between an actual 2.0 fusible link wire and a 12 gauge wire, or is it just the insulation thickness? What would cause the original fusible link to fall apart?
 

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Fusible link wire has a flame proof insulator covering. Replace with same length and gauge and crimp on new connectors just like the originals. After 35 years the insulation just gets brittle and breaks apart

You need this for the blue
14 Gauge Fusible Link Wire (2.0 SQ mm)
and this for the yellow
16 Gauge Fusible Link Wire (1.0 SQ mm)
the wire colors you buy may not be the same.
 

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Discussion Starter #16 (Edited)
After checking all the fuses 5 times and rebuilding the fuse link box, I still had the issue. The fused links in the fusebox had a little too much dielectric gel on them, but that was the worst issue. I gave up and swapped out the alternator with a spare I bought during the summer. Seems to work fine now. The speedometer needle still "bounces" when the car is accelerating at low speeds at first gear, but I am hoping that this is a minor issue.

A couple of more questions. Was this the correct way to repair the link box? This is about what it looked like before I pulled it apart. The yellow wire is the original. Also, I found a damaged connector near the battery. I am pretty sure that this is bad, but I don't know how to go about fixing it. Is there a connector for sale that would fit?

Also, what do I do with the old alternator? I don't want to just scrap it. Is it best to just give it to an auto parts store to recycle?
autoSupFuseRepSmall.jpg autoSupFuseInBoxSmall.jpg autoSupDamaLinkSmall.jpg
 

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Wire repairs look good. The bad connector top two red wires 15 amp headlight wires, yellow wire oil pressure sending unit and the green wire horn switch. Just replace with a generic 4 pin connector or solder together.
Scrap yard $3.00 or save for core deposit for future.
 

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What issues are you having currently??
 

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Regarding your previous question about spark plugs etc ( I cant find the thread??) Given the fact the plugs look like needing replacement, I would order all new rotor , cap and plug wires too IMO...
 
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