DESCRIPTION
Automatic A/C-heater system consists of electronically controlled components added to standard A/C-heater system. Automatic A/C-heater system is controlled by A/C-heater control panel (auto amplifier). (Scheme 1)and see scheme 2.
The auto amplifier is a switch control panel and micro-computer assembly. It processes various sensor information to automatically control outlet air volume, air temperature, and air distribution. Self-diagnostic functions are built into the auto amplifier.
Note. For A/C-heater components not covered in this article, refer to A/C-HEATER SYSTEM - MANUAL article in the AIR CONDITIONING & HEAT section.
Scheme 1
Checks Operation Of Each Actuator
- Ensure fresh vent switch on auto amplifier is off during tests. To enter self-diagnosis step 4, press temperature switch up arrow on auto amplifier.
- Display will illuminate Code 41. Each time defrost switch is pressed, display will advance one code number. After Code 46 is reached, numbers go back to Code 41.
- As code numbers advance, auto amplifier commands will change air intake and outlet routes. Ensure doors are switching properly by listening for door operation and/or feeling for airflow from proper outlet(s). See «SELF-DIAGNOSIS STEP 4 CODE EXPLANATIONS»(ref-35368-S22519139302001010900000) table to determine proper door positions.
| Application | Door Position | |
|---|---|---|
| Code 41 | ||
| Air Mix Door | Full Cold | |
| Blower Motor | (1) Low (4-5 Volts) | |
| Compressor | On | |
| Fresh Vent Door | Open | |
| Intake Door | Recirculate | |
| Mode Door | Vent | |
| Code 42 | ||
| Air Mix Door | Full Cold | |
| Blower Motor | (1) Medium High (9-11 Volts) | |
| Compressor | On | |
| Fresh Vent Door | Open | |
| Intake Door | Recirculate | |
| Mode Door | Bi-Level | |
| Code 43 | ||
| Air Mix Door | Full Hot | |
| Blower Motor | (1) Medium Low (7-9 Volts) | |
| Compressor | On | |
| Fresh Vent Door | Closed | |
| Intake Door | 20% Fresh | |
| Mode Door | Bi-Level | |
| Code 44 | ||
| Air Mix Door | Full Hot | |
| Blower Motor | (1) Medium Low (7-9 Volts) | |
| Compressor | Off | |
| Fresh Vent Door | Closed | |
| Intake Door | Fresh | |
| Mode Door | (2) Foot/Defrost Mode 1 | |
| Code 45 | ||
| Air Mix Door | Full Hot | |
| Blower Motor | (1) Medium Low (7-9 Volts) | |
| Compressor | Off | |
| Fresh Vent Door | Closed | |
| Intake Door | Fresh | |
| Mode Door | (3) Foot/Defrost Mode 2 | |
| Code 46 | ||
| Air Mix Door | Full Hot | |
| Blower Motor | (1) High (10-12 Volts) | |
| Compressor | On | |
| Fresh Vent Door | Closed | |
| Intake Door | Fresh | |
| Mode Door | Defrost | |
| (1) Voltage applied to blower motor for desired speed. (2) Foot/defrost mode 1 is used when manual mode is selected on auto amplifier. Mode 1 directs 78 percent air to foot area. (3) Foot/defrost mode 2 is used when automatic mode is selected on auto amplifier. Mode 2 directs 55 percent air to foot area. | ||
| (1) | Voltage applied to blower motor for desired speed. |
| (2) | Foot/defrost mode 1 is used when manual mode is selected on auto amplifier. Mode 1 directs 78 percent air to foot area. |
| (3) | Foot/defrost mode 2 is used when automatic mode is selected on auto amplifier. Mode 2 directs 55 percent air to foot area. |
SELF-DIAGNOSIS STEP 4 CODE EXPLANATIONS