Blower Harness Connector

[jfa.series1]

The intermediate wiring harness for the blower switch has a small connector that is not identified in the Supplemental FSM. The connector has provisions for 3 pins but has only two wires - red and blue. I'm referring to page 26 of the '71 Supplemental FSM.

As I reconnect my electrical system, I'm trying to ensure there are no orphans. I did not mark this connector back when I tore it down, so it may have been unused at that time.

Any ideas?

Thanks,

Jim

[Arne]

Jim, I believe that connector is for the rear defroster switch in the console. Later cars with lighted switches had three wires in it, Nissan was apparently planning ahead.

[jfa.series1]

Arne - I had the defroster switch wire marked and it is back together. It is part of the large bundle with the vinyl wrapper on the right side of the console.

Jim

[Arne]

Well then, the only other thing I can recall in that area on a Series 1 that is not in the diagram is the radio. The antenna switch connector has three wires, all in blue. I'd need to dig out my original radio to remember for certain how it is wired. I no longer have a Series 1 car to compare directly.

[jfa.series1]

The antenna switch is also accounted for. It too, is in the right side bundle. No cigar yet.

I just wrapped up all the dash area electrical connections this afternoon, including the steering column. No orphan male connectors with two wires anywhere in the area. I suspect this one is a factory orphan. Here is a picture of it and my almost complete dash install, this may stir someone's recollection.

Heck, if we get enough guesses, we may find a good use for it. :bulb:

Jim

[coopdog240]

I have a Series one and just re-connected my blower switch sub-harness. The three-pronged connector you describe takes power from the main harness and supplies power to the blower motor circuit. You can confirm that with a test light.

[jfa.series1]

Coop - thanks. I will dive back in there and search for a male connector on the main harness. It has to be very close because of the limited reach from the switch mounting point.

On the main power item, the FSM identifies a single red wire as providing the power, connection #55 on the diagram. I have that wire in place and connected to the main harness, as well as #56, the ground connected to the dash frame. Is it possible there is a difference in our two sub-harnesses? What is your build date?

Jim

[coopdog240]

My build date is 10/70. There are three connectors. Obviously one goes to the blower motor resistor and one goes to the blower switch. The third, the one you describe, goes to a matching connector on the main harness. The matching connector on the main harness has a hot line as one of the three wires.

I am having a similar problem to you. In my case, I cannot figure out what the individual red wire and the individual black wire on the blower sub-harness go to. When I plug the skinny three wire connector from the blower sub-harness into the matching connector on the main harness, the blower works (by the way, I did the Honda blower motor swap and it's great.) But I still don't know what the indivual red wire goes to. The red wire is hot when the ignition is on.

P.S. - If you connect the single red wire to a power source and also connect the three-wire connector to its matching counter part, I predict you will blow a fuse. One of us is wrong.

Edited July 3, 2011 by coopdog240

[coopdog240]

By the way, if you have the single red wire powering the blower and you plug in the three-wire connector too, you will likely blow a fuse. One of us has to be wrong.

[jfa.series1]

Ok, our build dates are close enough together to have similar or the same parts. I think what we are seeing is another of the evolutionary changes during the early build cycle.

My theory: the sub-harness started out with the small connector as the power source and ground. The wiring ga. was too light for the load so the single red wire (larger ga.) and the single black wire (larger ga. and a shorter ground length) were added to the harness as replacements. One look at the harness shows these to be after-thoughts, not well engineered into the original design.

That is why the '71 Supplemental FSB diagram shows the original connector as a "ghost" and does not identify it - they did not want you to use it. Use the two added wires instead. I completely agree with you that if both sets are connected, a fuse or two will go, or even worse!!!

When I pulled my dash, I did not disconnect the sub-harness, so my red wire and black wire remained attached as installed at the factory. That helps me explain why I did not tag the small connector - it was not attached to anything to tag as I broke various connections.

My red wire is attached in the large bundle to the right of the console, I will take a look and get back to you with what I find.

Jim

[coopdog240]

If power is coming from the harness to the three-wire connector, then I think the single heavy red wire must be used to power something else. There is really no other possibility. I am curious to figure this out too. I have figured out just about everything on my electrical system but not everything. I don't know which circuit powers the rear defroster in the hatch glass. That is one possibility for the heavy red wire from the blower sub-harness.

[jfa.series1]

Not to get into a debate, but I think you may be looking at the power flow direction incorrectly. I don't see the power as coming from the harness to the connector. If that is the case, where is the harness getting its power?

I see power flowing TO the switch from either the small connector OR the red wire. The switch then sends power thru the harness to the blower. Thus my argument above for an inflight engineering change to replace an inadequate power supply and ground TO the switch (the small connector) with a larger ga. wire and a shorter ground wire.

BTW, the rear defroster switch wire connects to a pair of blade connectors in the bundle to the right of the console: green/blue (switch wire) to blue, red (switch wire) to red/black.

Jim