76 280z ECM?

[JohnnyP]

Just below the hood release latch in my Z, there is a black box with two white female end plugs coming from the unit. I found two different sets of numbers:

The first set was on a green tag:

Part #: All-600 000

Lot #: 6310

For: L28

The second, on a white tag:

Part #: A14-100 003

Lot #: 6211K

Is this thing the Engine Control Module? If so where do I plug those white plugs into? I can't find any other plugs that could reach there. If anyone has any advice that'd be really helpful! Thanks a lot all of you.

John

[AnthonyG]

woah. mine has those too, and they aren't connected to anything. I'll double check tonite.

wonder what they're for.

i'd be sure they are good and insulated from the frame. one looks like it may have shorted to the frame at some point

(oh keep in mind mine is a manual)

Edited April 20, 2010 by AnthonyG
added transmission type difference

[Zed Head]

Yes, that is the ECM.

I have the same wires, non-connected. 1976, manual transmission. I looked closely when I was working on mine and decided that they weren't meant to be connected to anything full-time and just pushed them back under the cover. I could be wrong. That was quite a while ago.

Maybe they are for diagnostics or a switch bypass.

[JohnnyP]

Zed Head,

The possibility that they are for diagnostics or a switch bypass does sound about right. Thanks for the advice all.

John

[superlen]

An old thread but for posterity...Those wires are for the altimeter switch. CA models monitored altitude and would adjust the fuel pulse width if above a certain altitude. If yours isnt a CA model, the altimeter switch isn't there and the wires just hang.

Len

[Zed Head]

The altimeter wires must be there somewhere for CA models, but the wiring diagram says the white hanging wires are Control Unit Checking Terminals.

I should have found this a long time ago, considering all of the time I've spent staring at the 1976 wiring diagram.

BUT. Looking at the 1978 diagram I see that there is an altitude switch. But its wires are black. The white checking terminal wires seem to be gone in 1978. I don't see them on the diagram or on a spare 78 harness that I have.

One more interesting thing. I've seen it suggested that one could put a switch on those altimeter wires and use it to get a lean tune. Maybe for highway cruising gas mileage.

Edited December 30, 2013 by Zed Head

[superlen]

Zed,

The test harness I'm using for HellFire has white wires coming out for the altimeter not black. Go figure! That's why I assumed that the white wires from the OPs was the same. I have no idea what year this harness is from, it was just in a pile of them I had. Thanks for posting the pics showing the "Control Unit Checking terminals". I have never seen those referenced before.

I'll also double check my white wires to make sure they are in fact going to the altimeter switch.

Len