Fuse insta-blown! '78 a10

[datsun510eric]

My problem today is trying to figure out why i keep instantly blowing 30a fuses in the slot marked "9 10" dont have the box cover but this fuse works the marker, tail and dash light as well as that annoying buzzer. Also the fuse is hot to the touch once removed.

[MikeRL411]

Find and fix the short in the "marker, tail and dash light as well as that annoying buzzer".

[datzenmike]

There are no 30 amp fuses used in the A10. 20amp would be the highest. Using an over size risks melting the wires together and that's the end of it.

 

You have a bare wire touching ground. Could be pinched (I don't know if the rear harness runs under the rear seat) or a wire could have rubbed the insulation off. Someone may have wired in something like the light for a stereo and wired it wrong.

 

Unplug the harness at the tail lights see if the fuse still blows. Disconnect the dash harness and see. Try to isolate if it's the front or rear side marker lights.

[nismo dr]

 you have a short now find it. easy way to start ,you know whats on that circuit, "marker,tail, etc" now start unplugging those things until the fuse stops blowing, tht should narrow it down quite a bit

 

edit:: Mike beat me while I was typing

[banzai510(hainz)]

what you can do is put a test light in between the battery and the battery post. your test light will be ON

then disconnect the harness as Mike suggested till the test light goes out then you know the circut that is bad and then ck for a short. I have heard people running sheet metal screws in to hold soemthing and a whire gets shorted that way , or a seat gets installed smashing a wire.

 

also this is most likeluy the commong circut fuse light the cig lighter. so ck that also there isnt soemthing jammed in that

 

about 34 sec into the vedio is how to hook up the test light