3rd Gen Rear Defogger Resistance Wire?

[71charger_fan]

I have an NOS switch/light assembly with the short harness that plugs into it and I have the defogger assembly for under the package shelf. I have never had the harness that runs from the switch harness to the trunk. I ordered spools of white and black 18ga. stranded wire to build my own. However, in the wiring diagram the white wire is shown as a resistance wire. Does anyone know how many ohms? I'd like to add a resistor to the white wire to have two motor speeds instead of high and high.

[Nacho-RT74]

No resistance wire on rear deffog, but a mounted resistor into the blower housing with a baquelite plate, similar to the one  for A/C and Heater on box.

It gets a packard T plug ( two ways ) for it.

[71charger_fan]

It's odd that the '71 service manual clearly marks the white lead as a resistance wire. I wonder if there was a running change or if there was an engineering change after the manuals went to print. Next time I'm at the paint shop, I'll have to take a look at my motor/blower assembly. Thanks.

[Nacho-RT74]

71 manual is shared with 70 model year and I think earliers could be different. Maybe manual  is only detailing the earliers setup

[71charger_fan]

The '71 parts book is shared with '70, but the '71 service manual isn't. Here's the section of the wiring diagrams showing the defogger. I measured the resistance in the short piece of harness that plugs into the switch and got .8 ohms through the black wire and just over 3 ohms through the white wire of the same length. I'll have to wait 'til next week and see my motor/blower and see what it looks like. I bought it at a swap meet so I have no idea what year it is.

If you have access to the motor/blower in the photo you posted, can you measure the resistance through each terminal to the output to the motor? That'll tell me how much total resistance I need.

[70 sublime]

Maybe resistance just means the white wire plugs into the resistor side of the plug on the blower so when the dash switch is in the low setting the blower is turning slower ?

[Nacho-RT74]

No, that diagram shows the earlier setup with single plug to the blower.

Weird!

As far I know all 71/74 uses the mounted on resistor, not the resistor wire. The 71 diagram I have shows the mounted on resistor using dual wire to feed it. Will post the diagram later

My Charger is in Venezuela and I'm in Spain.