Battery terminal fuse

Big Studly

New Member
Jun 4, 2006
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My son just acquired a 2008 GT, a d we noticed a previous owner has butchered the battery/starter/alternator cables by splicing wires together with electrical tape.

After a starting issue yesterday, I am attempting to fix some of the issues. The stock wires are long enough to reach the battery terminals (except the alternator wire), so one of my solutions was to get a terminal connector with enough connections for each wire.

2 negative, but 4 positive. My question lies with the positive cable side. The alternator cable (the spliced portion from the stock cable) and the cable to the fuse box have been attached to a 120A fuse connector at the positive side terminal post. I have owned 3 Mustangs in the past and dont remember this being on any of the other (1965, 2005, 2010). Is this a standard part that I need to keep? Is it on the correct wires? I haven't been able to find a good photo online of the original wiring harness, or of the original battery terminal connection.

If anyone has any insight, I would appreciate it. I dont want to delete it if jts necessary.

Thanks.
 
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What you're describing sounds messy but is simply an alternative to the factory wiring. Originally, the alternator wire (6 awg - if i remember correctly) has a fusible link at the battery end (identifiable by its blue color) to protect the wire in case of overload. The fuse box wire was direct to the battery. The previous owner cut out the fusible link (which probably was a 10 awg equivalent) and replaced it with a connector and 120 amp fuse; and at the same time also attached the fuse box wire to the connector. This is okay and allowed him/her to replace the fuse in the event of an overload in the circuit. BTW, the closer the fuse is to the positive battery post - the better. Just clean up the wiring with good solder joints and you'll be okay.
 
Thanks for the reply. The alternator wire didn't have a fuseable link. Just the 120A fuse connector, that after rewiring everything I found out was blown. So it reality, everything connected directly up to the battery, and that is how I have it now.

I guess I need to find a 120A fuse.

Any suggestions on what to use? I found a 120A bold in cartridge fuse at Autzone like the one below, I just didn't know how to install it.

Amazon product ASIN B009WQPJP4View: https://www.amazon.com/Bussmann-BP-FLD-120-RP-Fusible-Terminal/dp/B009WQPJP4?ref_=fsclp_pl_dp_5
 
Hello, based on your last comments I am concluding that you are not overly familiar with automotive electric circuits. Also, I have the distinct impression that you have re-wired by eliminating the 120 amp fuse holder and going direct to the battery. Sorry if I sound like a dutch uncle but the combination of your knowledge base and your re-wiring is unsafe on several levels. Most importantly, the purpose of the fuse is to protect the wiring. What this means is that the wire gauge can only carry a specified maximum amp load before it burns; and the fuse is set to an amp level at or below that maximum. The fuse will melt before the wire can short-out, possibly avoiding a catastrophic or deadly situation. Also, the stock alternator is rated at 135 amps and a 120 amp fuse should have been sufficient for proper operation. The fact that the fuse was blown is an indication that something happened which caused the amp load to exceed 120 amps. You did not mention what wire gauge you replaced the fuse holder wiring but that could also be problematic. At this point I recommend that you replace the alternator harness with a stock wire or an upgraded one like this: PA Performance Premium Power Wire Kit

The cost is $50 and may seem a bit expensive but I'm sure we agree your son's well being is worth every penny.
 
Naw man, I'm good. I have an engineering degree and I have rebuilt a '65 Mustang, brought an '89 Bronco from the depths of hell, and have owned a '05 and '10 Mustang. I am confident I know what I am doing. That is why the lack of details. In the end, I just had a simple question, where do I get a 120 amp fusible link to put inline with the battery and alternator? Was hoping to find a fuse to install to restore the circuit protection until I could get to replace the alternator wire like the one you posted. I would rather have something than nothing, and right now (and I have no idea for how long) there is nothing. I guess I'll figure it out.
 
GREAT! You have the confidence and skill set to DIY. I apologize that I seemed too critical in my last post. Anyway, you can build a fused circuit for about $15 with the following parts (click on the link):

1. In-line MAXI fuse holder (6 awg lead wire)
2. 120 amp MAXI fuse
Of course, if the previous installation meets these specs and is undamaged, just re-use the fuse holder and buy new fuses.

First, DISCONNECT THE BATTERY and find a good place to mount the fuse holder or safely rest it on top of the battery (I think it's large at 4"L x 2"W x 1"H). Begin from the alternator side and cut and solder splice one fuse lead to the alternator harness. On the battery side you can re-use the ring terminal wire connection by cut and solder splice to the other lead wire of the fuse holder. Insulate the solder splices with quality heat shrink and install a fuse. Reconnect the battery. DONE!

DISCLAIMER: I am not recommending this procedure nor have I used these parts and/or method. Do this at your own risk. Good luck!
 
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Thanks for your help! I think I ran across that and was concerned that the wire size wasn't going to be large enough, especially since it says it's for a maximum 60 amps. It looks like it has 6 gauge wire, which does concern me given that 6 gauge is good to around 100 amps.

It does look like this may be a safer choice and I can use it as the splice instead of what I am using now so I don't have to replace the entire cable.

Amazon product ASIN B002NY9ESAView: https://www.amazon.com/SCOSCHE-PMFHIKA-Maxi-Fuse-Holder/dp/B002NY9ESA/ref=sr_1_17?keywords=4+gauge+fuse+holder&qid=1582575766&sr=8-17


Fortunately/unfortunately my ding dong child backed into a pole the day after I posted the initial question, so he hasn't been driving it, and I haven't been in a hurry to fix it, but I think this will work in the end.

Thanks again!