4 or 5 prong HVAC blower switch

[gramps77]

I need to replace my fan blower switch and what I'm finding is the A/C switch from the parts shops have 4 prongs. My truck came with those 4 plus another single spade for one orange wired connector. What is that one orange wire for?

[tucsonjwt]

I don't know, but you might peruse this AC Delco pigtail catalog to see if you can find a match for your existing connector.

http://www.acdelcotechconnect.com/pd...CH-0133-13.pdf

[Desert1957]

Originally Posted by gramps77

I need to replace my fan blower switch and what I'm finding is the A/C switch from the parts shops have 4 prongs. My truck came with those 4 plus another single spade for one orange wired connector. What is that one orange wire for?

What year truck????? With or Without A/C????

[motornut]

my 78 has three speed fan no off
my 79 has four no off

[chengny]

No voltmeter on the cluster right - just a generator warning light?

There should be 2 orange wires connected to the blower speed switch. One should be grouped with the brown and the light blue - that orange wire is the high fan speed.

The other orange wire is just spliced together with the brown hot wire that feeds the switch. It has nothing to do with the fan, it just was a convenient place to get a system (battery) voltage signal.

It is led over to the instrument cluster and is wired to one side of the "GEN" warning lamp. The other side of the lamp is wired to the generator. When battery voltage exceeds generator output voltage, current flows through the lamp and it illuminates.

[gramps77]

Originally Posted by chengny

No voltmeter on the cluster right - just a generator warning light?

There should be 2 orange wires connected to the blower speed switch. One should be grouped with the brown and the light blue - that orange wire is the high fan speed.

The other orange wire is just spliced together with the brown hot wire that feeds the switch. It has nothing to do with the fan, it just was a convenient place to get a system (battery) voltage signal.

It is led over to the instrument cluster and is wired to one side of the "GEN" warning lamp. The other side of the lamp is wired to the generator. When battery voltage exceeds generator output voltage, current flows through the lamp and it illuminates.

I actually do have a voltmeter. I do see now that it feeds back into the assembly the back side of the slider arms fit into.