'66 OEM relays

[jopizz]

The heater resistor is under the passenger side dash on the blower motor housing. That's the power window relay.

John

[Cwcb08]

The heater resistor is under the passenger side dash on the blower motor housing. That's the power window relay.

John

ok, thank you!

[simplyconnected]

Heater resistors are normally mounted so that the resistors protrude into the air passage. Moving air cools the ni-chrome resistors as reduced current lowers fan speeds. Air-cooling also means a smaller resistor can be used.

Problems arise when air flow stops. Then, resistors burn open. Usually the HI speed works because 12-volts is sent directly to the fan motor. - Dave

[Cwcb08]

after a quick google search i realize i have handled that part without knowing ( when i took the heater box cover off while trying to remove the leaking heater core before giving up trying to remove the back two bolts - for now ) is there a way to safely bypass that part to test the fan motor?

[simplyconnected]

Yes, simply apply 12 volts to the fan motor. You can do it at the resistor receptacle if you want.

[Cwcb08]

Yes, simply apply 12 volts to the fan motor. You can do it at the resistor receptacle if you want.

Fan works on high but only if the switch is at 3 and in just the right spot, with the resistor unplugged should the fan be on at every speed setting but at stay high speed?

Also found a few great photos on another forum and got the heater core removed, I can link them here if you guys like

[jopizz]

With the resistor unplugged it shouldn't work at all. The resistor completes the circuit to ground.

John

[Cwcb08]

With the resistor unplugged it shouldn't work at all. The resistor completes the circuit to ground.

John

well it's on the back seat and the fan is ON??





this is where i found the photos:

http://www.vintagethunderbirdclub.net/phpBB3/viewtopic.php?t=6676

[jopizz]

It's possible the switch is wired directly to ground on the HIGH setting and only uses the resistor on the lower settings. I've never looked at it that closely. That would make sense why your blower only works on HIGH.

John

[Cwcb08]

so i replaced the heater core and reinstalled the resistor, good news it works and i have three fan speeds.

i then i ran the motor for ten min (with a family members spare guage temporarily installed):



and flipped the lever to defrost but didn't feel any heat at the window?



i also grounded the bottom of the replacement temp sender straight to the battery and the stock gauge didn't move so im thinking i will have to contact dave for the CVR sooner rather than later and rule that out