1995 240sx : 75 amp fuse in the engine box keep poppin.

[PDX_S14]

my buddy's 95 s14 it keep popping the75 amp fuse in the engine fuse box. the 75 amp fuse is keep on popping when we start the car. that fuse which link to all the interior stuff and im looking at the FSM right now.... dont know where to start the diagnosic from. can someone give me some advice. thanks

[Silvia2b]

I'd have to guess that maybe it is a accesory that was added or connected recently that wasn't fused. Could you elaborate on the situation that occured when the fuse first blew? If it is an SE model the 75 amp isn't the main buse fuse. The 100amp is. Base models use a 75 main buss.

[PDX_S14]

is a 95 s14 base model...actully is evertime we connect the battery the 75 amp fuse pop right away..... the car start up and drives pretty good. we dont know when was the 1st time the fuse blown. we just pick it up not too long ago.....after we drove it home then we notice all the interior lights/gauges /tail light are not working .

[Silvia2b]

See that is a bit of a worry, since 75 amps is an awefull lot of current it probably means that there is a direct short somewhere, maybe from the fuse box in through the firewall if the grommet is worn or pulled out. You'll have to start examining wiring harness to check anyplace it is near bare or sharp metal.

[PDX_S14]

thats what i was thinking is in the harness cuz the car been hit at the front before.... i think we are going to take out the whole harness and start checking...... man... gonna be a lot of work... ill start checking sometime next week.... ill let you know how it goes..... thanks silva2b

[NISTECH]

Disconnect the alternator[connector and main lug] and recheck it for a short. make sure the lug is not touching ground when you hook the battery back up. If it dont blow anymore your alt has a short internally.

[PDX_S14]

ok nistech ill give that a try tomorrow.

[PDX_S14]

nistech.... ok it work.... i disconnect the the sub harness plugs and didnt pop.... then i went after the sub harness.... as i disconnecting all the plugs i notice the starter power wire was touching the throttle body.... so i guess whoever put the motor in before bented the tip of the power wire.... well now everything is working.... thanks again nistech !!