66 gmc 305e
 

Riddle me this.. does anyone know where these three wires go to?

Tan wire from the firewall. Appears to be the same wires Hooked up to heater control.

Green wire from the alternator

Blue wire also from the firewall

Re: 66 gmc 305e
 

Here's a link to a .pdf for a '67 truck. The wires are probably the same colors.

http://www.mediafire.com/file/zq2o83..._1966.pdf/file

Re: 66 gmc 305e
 

Judging from connectors and length:
Tan wire goes to heater blower motor.
Green wire goes to water temp sending unit by water neck

Blue wire? Where does it come from under dash?

2 out of three..

Regards
Steve
New Orleans

Re: 66 gmc 305e
 

Ok, blue wire should be oil pressure sending unit by oil filter on the other side of the motor.

3 out of 3.
Regards
Steve
New Orleans