Blend Door Actuator for Blazer

I have a 2000 S-10 Blazer that has no heat. Temperature gauge shows normal and blower works fine. A/c works perfect , too. I was told that it could be a blend door actuator that could be the problem. However, I can't find anything anywhere about where, behind the glove box, that could be and what it looks like. I was also told that there could be more than one, so I don't know how many I'm looking for to check or replace. If anyone out there could help me locate it , I would be very much obliged. Any advice or help is welcome.

Before you go ripping into the dash, do a quick underhood check. With the vehicle up to operating temp, check both heater hoses at the core. If there both hot you know you have flow through the core, not, then more than likely a pluged core.
With it cooled down check the coolant, look like mud? Hope not. If yes do a search to see how to flush.
The tempature door actuator is located on the top of the HVAC module, to the RH side, behind the glove box. It will be a small black box about 4"X4",
with a single connector w/5-6 wires. Good Luck.

Before you go ripping into the dash, do a quick underhood check. With the vehicle up to operating temp, check both heater hoses at the core. If there both hot you know you have flow through the core, not, then more than likely a pluged core.
With it cooled down check the coolant, look like mud? Hope not. If yes do a search to see how to flush.
The tempature door actuator is located on the top of the HVAC module, to the RH side, behind the glove box. It will be a small black box about 4"X4",
with a single connector w/5-6 wires. Good Luck.



Thanks for the info. I took vehicle into a radiator shop and had system flushed out and replaced with new coolant. Works perfect now! Thanks for the help!