What kind of HVAC unit does a GMC CK have?
I reverse engineered the AC Delco 15-72548 Heater AC Control Unit. This schematic is pretty accurate, but there are some component values / types missing, either because I could not decipher the part numbers, or I did not remove them from the circuit to measure them.
Where is the AC relay located on a GMC CK?
The AC Relay is located external to the controller. The coil of the AC relay is powered from the ECU, located on the left side of the engine bay. The High Pressure, Cycling, and Lo pressure refrigerant switches also go to the ECU. When all conditions are met, the ECU provides power to the AC relay coil, and the AC compressor clutch is energized.
How to recalibrate the HVAC actuator in a GM Truck?
For manual systems it does not matter where the a/c controls are set but if you feel the need to do something, turn the blower switch on (I prefer speed 3) and set the temperature sliders about .5″ to .75″ from full cold. For auto systems, press the auto button, with the key on. Turn the ignition off.
Where is the recirc door control on a GMC CK?
The Recirc door control is found at the center-left of the schematic. It is enabled by Switched +12V when the Blower is on at any speed setting. If the Blower is off, the Recirc door defaults to the fresh air position. The Recirc door actuator is closed when a ground is applied at Pin 4 of the Climate Control PCB.
I reverse engineered the AC Delco 15-72548 Heater AC Control Unit. This schematic is pretty accurate, but there are some component values / types missing, either because I could not decipher the part numbers, or I did not remove them from the circuit to measure them.
The AC Relay is located external to the controller. The coil of the AC relay is powered from the ECU, located on the left side of the engine bay. The High Pressure, Cycling, and Lo pressure refrigerant switches also go to the ECU. When all conditions are met, the ECU provides power to the AC relay coil, and the AC compressor clutch is energized.
The Recirc door control is found at the center-left of the schematic. It is enabled by Switched +12V when the Blower is on at any speed setting. If the Blower is off, the Recirc door defaults to the fresh air position. The Recirc door actuator is closed when a ground is applied at Pin 4 of the Climate Control PCB.
What kind of HVAC does a Chevy Silverado have?
Access our free HVAC Systems Repair Guide for Avalanche, Sierra, Silverado, C&K Series, 1999-2005 through AutoZone Rewards. These diagrams include: Fig. A/C Compressor Controls (c) (2005) Fig. Air Temperature Actuators Left and Right (c) (2005) Fig. Power, Ground, Serial Data and Blower Motor Control (c) (2005) Fig.
Where is the climate control PCB located on a GMC CK?
It is separately powered on Pin 1 from the dash light dimmer, and has no function in climate control, other than illumination. The climate control PCB is powered when the ignition switch is in the RUN position via Circuit #141. +12V comes in on Pin 5 in the upper left corner of the schematic.
It is separately powered on Pin 1 from the dash light dimmer, and has no function in climate control, other than illumination. The climate control PCB is powered when the ignition switch is in the RUN position via Circuit #141. +12V comes in on Pin 5 in the upper left corner of the schematic.