64 master fan switch

[Deanoko]

Hey guys, 

Once I have this last gremlin sorted I can quit asking these questions and just enjoy the car!

Is the blower master switch buried up under the console behind the heater / ac controls in the same unit as the 2 fan switches?

My issue is that the fan runs on low with both the fan switches off and the heater + ac controls off.  The heater fan switch works normally, except for never shutting completely off ie it does step up through the settings from low to high.  The AC fan switch does nothing, (completely inoperative) when I know it should blow electrically unresisted air at the highest setting.  The only ac I get is by using the heater fan switch.  I replaced one of the vacuum door actuators with new, and the other appears to work as advertised. 

Wondering if there's a vacuum logic problem, adjustment, or electrical issue?

Anyone have a similar issue they've solved? 

[1965rivgs]

  Yes, the master switch is mounted in the control unit which houses the AC and heater switches.

  If you look closely at the AC fan control you will notice the lowest fan setting is labeled "low"...not "off".

  The high blower relay is located on the passenger inside fender well.

  The vacuum system is not involved in the blower electrical circuit.

Tom Mooney

Edited August 13, 2023 by 1965rivgs (see edit history)

[Deanoko]

Thanks Tom.  Does this mean that it's normal for the blower to always be running in low, or is that only the case when the AC levers are not off?  I wonder if the electrical contact for that fan logic is on the far left or on the other 2 labeled click stops?

Deep dive.

Do you know if there is a weak point which is the "usual suspect"?

[1965rivgs]

  The lever trips the master switch. If the lever is all the way to the left the master switch should be open and not sending voltage to the manual switch. When you move the lever from left to right the master switch should close and send voltage to the manual switch. If the manual switch is on "low" you should get the low blower speed.

  When you move the lever you should hear an audible click when the master switch cycles. When you look at the control head and operate the lever you will see what is involved with actuating the master switch.

Tom