71 240Z complete electircal failure

[Skybird]

Folks, got one I can't figure out. My car is in great shape. Everything appears to be originally configured, especially wiring. Going around a left turn corner at 25 MPH, lost all electical. Got a puff of smoke from the right side under the hood. Power cable off of the starter was cooked. No other symptoms. Had just replaced the battery cables with marginal ones. Have fixed that with good fabricated ones. Battery checks good. All fuses that are obvious are good. Starter checked bad at Auto-zone and the new replacement changed nothing. I have horn and emergency flashers only (off batter I assume). I replaced the ballast resister, no joy. The ingition switch is new, 6 months old. Any ideas, single points of total electircal failure to check out?

Skybird

[d240zx2]

Sounds like your battery failed, and if not tied down, slid over and shorted the POS terminal to sheet metal.

[spotty]

Did checking the fuses include the fusable link?

[JimmyZ]

With your battery hooked up to a load are you still getting decent voltage? How was the battery tested? If you try a new battery or simply hook some jumper cables I'd try testing the main supply wire for the harness. (White wire with red stripe)

The large white wire with the red stripe provides your entire electrical system it's "+" side. (except starter high amp cable of course). This white/red stripe runs through your ammeter gauge and down to the fuse panel. Use a voltmeter to check this wire starting at the starter terminal where it originates working back through the dash. Hook the negative lead of your tester to batt ground and use the positive pointed tip to pierce the insulation at various points. It will help to have a load on the wire so have your headlamps ON during the test. This way if you had poor contact somewhere you would clearly see the voltage drop.

The three most likely areas to have trouble are down by the starter, on the back side of the ammeter or the harness connection to the fusebox. (which is behind the heater panel)

On my car I had a bad crimp connection give me intermittent power loss much like you have just had. Mine was a bad crimp where the short starter line plugged into the main harness white/red wire.

BTW it is not uncommon to have things get baked in the vicinity of the ammeter also. When I had my dash out I found a few wires with melted insulation around the ammeter. Fixed 'em of course.

Hope this helps.

Edited May 27, 2010 by JimmyZ

[clayton 260z]

I agree with spotty. Check your fusable links...

[zcar70]

Got to be the fusible link on the starter......

[gnosez]

I think so too (fusible link) but the white puff on the right side says battery tie-down failure to me and it could have also melted wires leading into the generator/alternator wiring.

I had mine fail due to a similar issue and the extent of the melting was not limited to just the fusible links.

[Skybird]

For all who are helping, thanks. Got some things to check out now. The battery first. Make sure it is not fried. I did not realize the wire at the starter was a fusable link and so replaced it with standard wire. Still no joy. Could be the battery is cooked, or something else. Will start troubleshooting the recommendations and keep you posted,

Regards,

Skybird

[dimitri_zee]

I've seen ammeters fail also; check it for continuity... or probe a test light under the rubber boots and make sure power is available on both sides..

[zcar70]

You might want to consider a different battery as well. I changed mine out so that the positive terminal is on the ENGINE side of the bay. Got a slightly shorter battery with the negative terminal on the outboard side, positive inboard.

One of the few design problems with the S30. If the battery breaks loose, there is not much room for error. the positive terminal will make contact with the chassis (under the fender) and cause a major short.

[Gary in NJ]

You might want to consider a different battery as well. I changed mine out so that the positive terminal is on the ENGINE side of the bay. Got a slightly shorter battery with the negative terminal on the outboard side, positive inboard.

One of the few design problems with the S30. If the battery breaks loose, there is not much room for error. the positive terminal will make contact with the chassis (under the fender) and cause a major short.

Can you provide make & model for that battery? Does the OEM battery hold-down work with this battery?

[Bonzi Lon]

Glue a piece of rubber innertube to the underside of the chassis where the positive terminal would touch. Worked for me.

Bonzi Lon