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**hatzie** · 08-03-2020, 02:16 PM

The motor under the kick panel on the bottom is the LH blend door motor that changes the LH cab temp from hot to not.

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The one on the LH end of the airbox near the go pedal is the Mode door. It moves the mode flap that directs airflow out of the HVAC box to the Defroster vents, the dash vents, or down to the floor vents depending on what you ask it for.
The motor on top of the airbox is the RH blend door motor that changes temp from hot to not. You can get to this one by removing the radio and reaching through the hole... supposedly. It's under a duct so I wouldn't count on it but it's worth a try.
The Recirculation door motor controls the recirc flap that selects outside fresh air or recirculates the stale cab air from the RH floor area. This one is buried behind the glovebox in a pretty miserable location to access.

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08-03-2020, 02:16 PM	#7
hatzie Moderator Join Date: Oct 2008 Location: Wentworth, NH Posts: 4,961	Re: HVAC Blend Door issues. Control head or actuators? The motor under the kick panel on the bottom is the LH blend door motor that changes the LH cab temp from hot to not. The one on the LH end of the airbox near the go pedal is the Mode door. It moves the mode flap that directs airflow out of the HVAC box to the Defroster vents, the dash vents, or down to the floor vents depending on what you ask it for. The motor on top of the airbox is the RH blend door motor that changes temp from hot to not. You can get to this one by removing the radio and reaching through the hole... supposedly. It's under a duct so I wouldn't count on it but it's worth a try. The Recirculation door motor controls the recirc flap that selects outside fresh air or recirculates the stale cab air from the RH floor area. This one is buried behind the glovebox in a pretty miserable location to access. __________________ 1959 M35A2 LDT465-1D SOLD 1967 Dodge W200 B383, NP420/NP201 SOLD 1969 Dodge Polara 500 B383, A833 SOLD 1972 Ford F250 FE390, NP435/NP205 SOLD 1976 Chevy K20, 6.5L, NV4500/NP208 SOLD 1986 M1008 CUCV SOLD 2000 GMC C2500, TD6.5L, NV4500 2005 Chevy Silverado LS 2500HD 6.0L 4L80E/NP263 2009 Impala SS LS4 V8 RTFM... GM Parts Books, GM Schematics, GM service manuals, and GM training materials... 1973-1991 GM Light Truck Service, Unit/Overhaul, Wiring Manuals, Parts Books and Some 1968-1999 GM Service Training textbooks in PDF 1988-1998 GMT400 CK service manual project 1988-1993 GMT400 CK parts books. 1967-1972 GM Light, Medium, & Heavy Truck Service Manuals in PDF Please include at least the year and model in your threads. It'll be easier to answer your questions. And please let us know if and how your repairs were successful.