2 red wires to battery?

[77-Z]

My son and I are working on a 1977 280Z and are stumped with some electrical issues (surprise!)

The primary issue I need help with right now is know where to hook one of the 2 red wires that come out of the wiring harness near the battery. One of the wires has a male connector, which hooks to the positive battery terminal via a fusible link. The other red wire has a female connector but does not connect to anything... I read somewhere that this probably connects to the negative battery terminal, however there are no wires coming from that area. ???

This is a new project car and it's possible a wire is missing or fell off in transit. Any help is greatly appreciated.

77-Z

[Walter Moore]

I can't read the diagram in my Haynes manual because the reduction is too small. I strongly suggest that you download the factory service manual for your car here:

http://www.xenons30.com/reference.html

This and many more questions are waiting to be answered there.

Good luck.

[=Enigma=]

Viewing a wiring diagram for a 76, it appears that the red wire with the female connector leads to the ECU, and goes to the (-)NEG battery terminal. I suggest you double check this against a diagram for a 77 and optimally, trace the wire to verify where it goes to before making any connections.

[sblake01]

Try this one. It's large, in color and for a 77:

http://www.classiczcars.com/downloads/F77ZCAR-WIRING.pdf

[=Enigma=]

Nice one Stephan. I forgot all about this one. Much easier to read.

[IdahoKidd]

Let us know if you get it running so the next guy that searches the archives might find an answer he needs.

[77-Z]

Thanks for the input...

Walter , I found the FSM at the site you posted - it is a great help!

=Enigma=, thanks for the guidance on the wiring & attached pix -- I traced both red wires from the battery area to the driver's side fender where they disappear at the base of the firewall. Do they split different ways at this point or tie into the main wiring harness and go through the firewall? I have yet to unwrap the two red wires or any of the harness - not sure the best way to unwrap/rewrap?

sblake01, this wiring diagram is awesome and will also help track down the wires - thanks!

I'll be sure to repost when I trace the wires and reattach any missing ground.

One other question - are "fusible links" available at any chain auto stores or via web only?

Thanks again!

77-Z

[sblake01]

All I did was pass the diagram on to you. Thank Wayne (wal280z), he's the one that originally posted it here some years ago. I have some tested, working, clean fusible links (3 red, 1 black). I used to carry them in the glove box as spares when I had my Z. PM me if you want them, they're yours for postage. (Like the 'pay it forward' thread).

[wal280z]

Thanks for the input...

Walter , I found the FSM at the site you posted - it is a great help!

=Enigma=, thanks for the guidance on the wiring & attached pix -- I traced both red wires from the battery area to the driver's side fender where they disappear at the base of the firewall. Do they split different ways at this point or tie into the main wiring harness and go through the firewall? I have yet to unwrap the two red wires or any of the harness - not sure the best way to unwrap/rewrap?

sblake01, this wiring diagram is awesome and will also help track down the wires - thanks!

I'll be sure to repost when I trace the wires and reattach any missing ground.

One other question - are "fusible links" available at any chain auto stores or via web only?

Thanks again!

77-Z

The two red wires that I believe you are referring to supply the positive and negative supply from the battery to the FI control unit. The Positive has a fusible link and the negative does not. If I recall correctly, the connectors are (originally) keyed so that the polarity cannot be switched. There is a picture in this thread that shows off my maxi-fuse upgrade, but it does show the battery connection with the two red wires you refer to. The negative is in the foreground, positive (fusible link shown) is beyond. If you need another picture (without the fusible link covering up the connections) let me know.

*edit* Both wires *should* go to the FI control unit only - but confirm with the diagram for that.

All I did was pass the diagram on to you. Thank Wayne (wal280z), he's the one that originally posted it here some years ago.

Stephen - Thanks for the kudos! Wow - I just realized it has been nearly six years since I posted that thing!

Edited January 6, 2010 by wal280z

[77-Z]

Wal280Z,

I appreciate your input to my dilemma - I rechecked the diagrams as well as my wiring and am SURE the other red wire DOES attach to the negative battery post! I happened to find more confirmation via some digital pix my daughter took when I gave this car to my son. Some of the pix showed me standing next to the engine compartment and there WAS a wire attached to the negative battery post when I bought the car (which must have fallen off about the time the car stopped running).

My son (Clay, 17 years old today) is the one I bought the car for and we hope to fix the wiring issue asap. I'll post and let you know how it goes.

THANKS AGAIN for everyone's help in getting my son's dream car back on the road!

Mark

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The two red wires that I believe you are referring to supply the positive and negative supply from the battery to the FI control unit. The Positive has a fusible link and the negative does not. If I recall correctly, the connectors are (originally) keyed so that the polarity cannot be switched. There is a picture in this thread that shows off my maxi-fuse upgrade, but it does show the battery connection with the two red wires you refer to. The negative is in the foreground, positive (fusible link shown) is beyond. If you need another picture (without the fusible link covering up the connections) let me know.

*edit* Both wires *should* go to the FI control unit only - but confirm with the diagram for that.

[77-Z]

quick update...the "unattached red wire" WAS the problem and solved several issues:

> fuel pump now has constant/proper current

> fuel injectors now injecting fuel into cylinders

> car actually STARTS!

Other issues are now waiting to be tackled but fall under a different category (which I'll post and trust I find the same helpful info I got here)

Thanks again!

Mark (aka 77-Z)

----------------

'77 Datsun 280Z (son's project/dream car)

'61 Ford Falcon (2nd project car)

'65 Ford Mustang (wife's 40th bday present)

'93 Mercury Villager (my boring work van)

[=Enigma=]

That's great news Mark. Congrats on getting her running.