Wires Behind Heater Center Control Panel? 1972 240z

[moritz55]

I'm reparing my Heater Center Console Panel, adding a New Fuse Box from MSA and installing a New Stereo on my 1973 240z. The prior owner messed it up pretty bad when installing the Stereo 12years back, so I decided to do some major repairs and restoration.

Removal of the Heater Control Panel was easy! Thanks to a prior thread read post #5 by EScanlon: http://www.classiczcars.com/forums/showthread.php?t=4429&highlight=Center+Control+panel

Once I started looking at the wires I noticed many issues and questions as I expected. I can use some help identifying several wires, connectors and recommended fixes of diagnostic approaches.

1) There is a 3prong relay (photo #000) on the driver that was unplugged. I plugged it in and the car runs fine. What is this and should it be plugged in?

2) There is a Red wire with Male bullet connector from the Fan/Blower harness (photo #001) that I believe was connected to a Blue Female bullet connector on the passenger side (photo #002). Is this correct?

3) There is a spare Blue wire Female bullet connector in the Fan/Blower harness (photo #2). What is this is for? Possibly an AC option?

4) There is a 3 Prong Female connector (Photo #003) with White/Black, White and Blue wires and is connected to the Fan Blower harness. What is this for? Possibly an AC Option?

I have additional questions so see the #2 post below. I could not post more that 4 photos.

Any help is very much appreciated.

[moritz55]

This is the 2nd part of my post above... on wires behind the clock. My clock is removed and has a Vacumm gauge installed, so I know the light is the former clock light. The photos are in Post #3. I had problems again posting the photos...tx

5) Behind the Clock there is a Light, and 3 bullet connectors(Photo #004). 1st bullet has a Black Male bullet wire plugged into a Blue Female wire connector. 2nd bullet has a Black Male bullet wire plugged into a Red/Blue Female wire bullet connector. 3rd bullet is a Female Red/Blue bullet wire that was connected to the Map Light male Red wire(photo #005). Since my Map light never worked - I assume this is incorrect. What would the correct wiring look like? What should the Red Male bullet Map Light connect to?

Any help here is appreciated

[moritz55]

Here ar the photos for post #2 above. Many thanks...

[Ttiger]

As I recall, the map light power lead came from the clock area as well. It's hot all the time. That short blue wire down by the fan is an extra lead for who-knows-what. There should also be a black ground wire going to the map light. I'm not sure what that 3-prong relay does and that plug in 003 looks like the dash light plug for the heater control panel if you have a '72 made after 8/72. If it's an early '72 then it's switched by ignition and not used for anything I could find.

According to the wiring diagram, if that plug in 003 has red and red w/green stripe wires, it's a fog light switch connector. A/C power shows to be a solid blue wire. All the power antenna switch wires are solid blue and blue with colored stripes (white, red)

It looks like the solid red wire in 001 is a feed wire, in that it gets plugged into a hot lead. They would not leave a bare exposed wire that's hot. All the wiring that has power has a covered terminal.

[moritz55]

Ttiger - many thanks. Today I did the diagnostic work using an Amp/Volt meter. I uncovered several problems and resolved them.

1) The 3 Prong Relay (Photo #000) with Black, Green & Green/Red wires is still plugged in and the car continues to run fine. It's still a mistery?? Any help on identifying this is appreciated! - Unsolved !

2) The Red Male Bullet wire (Photo #001) is the HOT feeder wire for the Blower/Fan. It pulls from an inline fused Blue Female Bullet wire (Photo #002). It's on the same Circuit as the A/C with a 20amp fuse. This checks out good and matches the schematic I have from Haynes. - Solved !

3) In Photo #004, the Blue Female Bullet wire that was plugged into the Black Male Bullet wire WAS were the original clock plugged. The clocks been gone, so the prior owner connected these togther! Guess what - it blewout the 10amp Fuse for the Map Light & Dome Light and every time I replaced the 10amp fuse it kept blowing! So.. thanks Ttiger you were correct... the Map light is on the same circuit, so once I disconnected the the former clock wires and replaced the fuse, plugged the Map light into a Red/Blue(+) and Black(-) leads, it and the Dome Light work perfectly. - Solved !

4) So the 3prong plug in Photo #003 has white, white/blue (not white/black as I thought) & blue wires were to the rear speaker and antenna from the stock radio. My retractable antenna is wired with a 3 postion switch and decoupled from the stock radio circuit. - Solved !

5) Finally - as I was debugging the Heater Console Lights (Red/Blue wire & Black wire) I noticed it was plugged into the 2prong plug (Green/White wire & Red wire) on the Fan/Blower/AC harness? As I was inspecting the harness - I noticed another 2prong mating plug with Red/Blue & Black wires matching the Heater Console lights! You guessed it, after plugging the Heater Console Lights into this matching 2prong socket with Red/Blue & Black matching wires, the Heater Console lights are now on the Dash Dimmer and go On & Off when the Lights are turned On & Off. As I now recall - my Heater Console Lights were on all the time when the car was running! So a Happy Accident - Solved !

Anyway, made a lot of progress today and di get my car ready for the New MSA fuse box and Stereo!

Many thanks again Ttiger ...

[cnwayland]

So, I'm bringing this back from the dead. I'm inside the dash of my '72 currently trying to figure out what's going on with my recently refurbished blower. I tested it while out of the car and now I'm trying to figure out what's going on.

I hooked the red wire that comes off of the fan wiring harness into the blue in-line fuse wiring and I have sparks coming from what I thought was the ground (black wire, coming from the wiring harness that connects the blower motor and the fan switch.

I believe this is the blue in-line fuse you were referring to? I've actually go two! One comes out of the harness for the in-line fuse and then back in, and the other blue in-line fuse terminates as an open connector.

There's also this strange blue wire that terminates into a fuse but goes no where... no clue. I'm holding what I thought was the ground on the harness.

[liam_irish]

Did you ever figure this out? I am having a similar issue. I just had my blower motor refurbed, reinstalled, and am trying to get it to work again. I have the red wire coming off of the fan harness plugged into the blue in-line fuse wiring, and have touched the ground to metal to see if I could get it to work. I have no sparks, but the blower fan will not turn on. Am I correct that the black ground wire connection and red wire to blue fused wire are the only connections you have to make? The reason I ask is that I have one female three prong plastic connector coming off the fan harness with red and blue wires that is not hooked up to anything (just like the one in the very center of your photo #001) - is that correct? If I have it wired correctly, I may try grounding somewhere else to see if I can get it to work....

[liam_irish]

I had it all wired properly, just had to replace the inline fuse that must have blown when I initially connected the wires the wrong way. Once I had everything connected as described in my previous post and replaced the fuse, everything works! :-)

[jalexquijano]

Can you use the controls in the heater panel to opérate an air conditioning kit? I just a bought a 1972 Datsun 240z that has no air conditioner and want to confirm if i purchase a kit i will be able to use the heater control instead of the control the aftermarket kit brings.

I am considering this kit but they have informed me that the kit only Works with their control:

Datsun 240Z 260z 280z Complete AC System | eBay

Edited December 30, 2013 by jalexquijano
more info

[psdenno]

Can you use the controls in the heater panel to opérate an air conditioning kit?

| eBay

No. The heater panel controls can only control your vents and heat. Your car is 41 years old and wasn't designed for factory HVAC. Honest - most cars actually didn't have AC when early Zs were built. Hence, aftermarket AC.

I first had AC installed on my Z in 1972 for $325 parts and labor. I replaced that unit a few years ago with a current kit from MSA at a cost of a bit over $1,600 parts & labor.

Dennis

[jalexquijano]

PSDENNO,

 

What additional controls will i need to turn on the AC compressor and dial its blowing speed? WIll the A R A controls match with a Vintage air gen ii mini kit and sanden 508 compressor?

 

http://www.summitracing.com/int/parts/vta-66005-vuz-a/overview/

Edited September 1, 2015 by jalexquijano