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 #379172  by cin993
 June 1st, 2019, 11:07 pm
I diagnosed a bad negative battery terminal/cable right at the battery post. Any thoughts on either replacing the cable or soldering in a new section?

Last Fri car was stone cold dead-- no crank, no start, no headlights, no interior lights, nothing.

12.49 volts directly at the battery posts.

Wiggled the negative cable connection at the battery and car came back to life as normal.

Even NAPA does not have the battery terminal where i can insert my cable and solder it, Any suggestions?



I was going to use this one here, solid 4 gauge copper, connect it to the battery and cut the opposite end and solder that end of the cable to the existing negative cable... and use some heat shrink with waterproof adhesive inside.

Some of these cable are clad in PVC, some vinly. What is the best?

I'd like this repair to the neg cable terminal to be as strong as OEM. Thanks.
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 #379413  by ggariepy
 June 18th, 2019, 10:26 pm
I believe the negative cable goes from the battery directly to the post on the passenger side shock tower. You should not break the insulation on the cable, or extend an existing cable. It will cause no harm if the replacement cable is a few inches longer than the original. With cable that heavy, soldering it properly is going to be difficult at best. I have my doubts that the flux will be able to get the solder to flow all though the cable; it's likely to result in a cold solder joint unless you get it hot enough to make the insulation melt. I wouldn't do it.

If you're really having a difficult time finding something, stop by a welding shop and get some welding cable. Cut it to the right length, strip the ends and install a generic negative terminal at the battery end (make sure it's the right size for the negative!) and an eyelet at the other end. Route it up and bolt it down to the shock tower.

Of the two types of insulation, my preference would be to go with the one that is the most pliable.
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 #379432  by LUNAT1C
 June 19th, 2019, 10:43 am
If it were me and I didn't need my aftermarket expansion terminal, I would install the entire replacement cable and call it a day.

Alternatively, cut off the bad terminal and crimp on a new one if the rest of the factory cable is OK.

It doesn't make sense to me to buy an entire replacement cable, only to cut the terminal off to replace the factory terminal, unless there is some I'm missing.

Cable that thick can be soldered. Audio shops do it all the time with 0 gauge. In that case, they rig up the stripped cable with the lug in place, and heat it with a torch, feeding in the solder until it's brimming. Yes, it sometimes catches fire if held in place too long. Stop heating and blow it out, then continue. Cover the joint and insulation with a good heatshrink.

But, I'm fairly certain the factory terminals are crimped and not soldered. I believe mine were when I cut them off and chucked them 10 years ago. I'm currently using aftermarket terminals designed to allow 0 gauge and 4 gauge wiring to be added, in addition to the factory wiring. I have the factory wiring in one of the 4-gauge openings. Big 3 upgrade in the second 4 gauge opening. Audio system 0 gauge welding cable in the 0-gauge opening. They use compression fittings via a set screw. I've been using my current set for over 5 years now without issue. They also feature a standard screw that eyelets can be fitted to, adding additional accessories, which I'll be making use of in the next few weeks when I add a supplemental relay system for my added lighting systems.
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 #379437  by ggariepy
 June 19th, 2019, 9:54 pm
LUNAT1C wrote: June 19th, 2019, 10:43 am
But, I'm fairly certain the factory terminals are crimped and not soldered.
I'm pretty sure the one on mine is the factory original. The negative terminal is a steel ring, not the typical lead/bolt combination. Mine was somewhat corroded when I got the car and I've disassembled and cleaned it up. However, the battery appears to be five years old and it's marginal at best, so I'll be replacing it soon. While I'm at it, I'm going to replace both of the terminals. If I find corrosion in the wire I'll swap out the cables, too.
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 #379438  by ggariepy
 June 19th, 2019, 10:03 pm
Forgot to mention that yes, the negative terminal on mine IS crimped.

Thanks for the info about the soldering. I've soldered stuff successfully up to about 10 gauge wire or so, but haven't ever attempted anything heavier than that. My dad was an Air Force reservist who went to radio school, and he passed along the soldering knowledge to me at an early age, but usually when I'm doing that the typical wire size ranges from 14-22ga, not 0! :-)
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 #379443  by LUNAT1C
 June 20th, 2019, 9:26 am
ggariepy wrote: June 19th, 2019, 10:03 pm Forgot to mention that yes, the negative terminal on mine IS crimped.

Thanks for the info about the soldering. I've soldered stuff successfully up to about 10 gauge wire or so, but haven't ever attempted anything heavier than that. My dad was an Air Force reservist who went to radio school, and he passed along the soldering knowledge to me at an early age, but usually when I'm doing that the typical wire size ranges from 14-22ga, not 0! :-)
There are a lot of youtube videos out there. Steve Meade Designs comes to mind as one I've watched showing himself doing it. My 0-gauge welding cable uses a set screw in the battery terminal, fuse holder, and distribution block in the amp rack, so I didn't need to use terminal lugs.