What does the main 40a fusible control? If the.

Tiny
EDDYMAN30
  • MEMBER
  • 1990 TOYOTA CAMRY
  • 197,800 MILES
What does the main 40a fusible control? If the bottom of that link and the wire to that link is burned thru, could that kill my battery and alternator? Was told I need a alternator, I replaced it and still needed jumps to start my car and now I'm told my battery is bad
Thursday, November 1st, 2012 AT 4:17 PM

7 Replies

Tiny
WRENCHTECH
  • MECHANIC
  • 20,761 POSTS
If it's a 40amp fuse, then it's not the main fuse. It's simply a supply circuit for something high draw or it may be feeding other smaller fuses. There should be more than one of that size fuse.
You need to test the charging to find out if you still have issues there.
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Thursday, November 1st, 2012 AT 4:28 PM
Tiny
EDDYMAN30
  • MEMBER
  • 28 POSTS
It's a little fuse box connected to the positive battery terminal and on top of it the first is main 40a, then, alt 80a and am2 30a and I took my car back to the shop that put the alternator on and they checked it and told me the battery is bad, I just was wondering did that fusible link kill the alternator and batt or is the link related to something else like my headlights not working
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Thursday, November 1st, 2012 AT 4:45 PM
Tiny
WRENCHTECH
  • MECHANIC
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Fusible links or fuses don't kill anything, they protect circuits. You can easily test fuses to see if they are good or not but I have no idea what the fuse you are referring to even feeds. The 80 amp would be the only one associated with the alternator so make sure that one has continuity.
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Thursday, November 1st, 2012 AT 4:57 PM
Tiny
EDDYMAN30
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Can those be tested with a testlight?
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Thursday, November 1st, 2012 AT 5:03 PM
Tiny
KHLOW2008
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The 40A fuse is for the headlight relay, dome lights, horn and hazard. It is not related to the charging system.

A faulty alternator can kill a failing battery.
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Thursday, November 1st, 2012 AT 5:05 PM
Tiny
EDDYMAN30
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Now I know that is related to my headlight problem and yeah its the battery then, thank you so much, appreciate your help
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Thursday, November 1st, 2012 AT 5:13 PM
Tiny
KHLOW2008
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You're welcome.
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Thursday, November 1st, 2012 AT 5:17 PM

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