HVAC Module Cold Boot Process
WARNING: This page is about a different car, the 2007 Lincoln Mark LT and 2007 Ford Pickup. However, it is still accessible from the selected car via links, so may be relevant.
The purpose of the cold boot process is to allow the HVAC module to re-initialize and calibrate the door actuators. To carry out the cold boot process, follow the steps below.
- Turn the ignition switch to the OFF position.
- Disconnect the HVAC module electrical connectors.
- Wait one minute.
- Connect the HVAC module electrical connectors.
- Turn the ignition switch to the ON position.
- Select any position except OFF on the HVAC module.
The HVAC module will now initialize and calibrate the mode doors. Calibration of the mode doors will take approximately 30 seconds.
NOTE:
Some PCM DTCs may inhibit A/C operation. If any PCM DTCs are retrieved, diagnose those first. Refer to the INTRODUCTION - GASOLINE ENGINES
article.
HVAC MODULE - ELECTRONIC AUTOMATIC TEMPERATURE CONTROL (EATC) DTC CHART
| DTC | HVAC Module- EATC DTC Displayed | Description | Action to Take |
|---|---|---|---|
| B1200 | 9200 | Stuck Button | Button held too long may set DTC. Attempt to clean buttons. If code returns, INSTALL a new HVAC module - EATC. REFER to CLIMATE CONTROL article. |
| B1251 | 9251 | Air Temperature Internal Sensor Circuit Open | Go to Pinpoint Test A . |
| B1253 | 1253 | Air Temperature Internal Sensor Circuit Short to Ground | Go to Pinpoint Test A . |
| B1263 | 1263 | Servo Motor Vent Circuit Failure | Go to Pinpoint Test D . |
| B1342 | 1342 | ECU Is Faulted | INSTALL a new HVAC module - EATC. REFER to CLIMATE CONTROL article. |
| B1676 | 1676 | Battery Pack Voltage Out Of Range | Go to Pinpoint Test F . |
| B2266 | 2266 | Left Side Blend Door Circuit Failure | Go to Pinpoint Test D . |
| B2268 | 2268 | Steering Wheel Climate Control Circuit Open | Go to Pinpoint Test E . |
| B2269 | 2269 | Steering Wheel Climate Control Circuit Short to Ground | Go to Pinpoint Test E . |
| B2477 | 2477 | Module Configuration Failure | CONFIGURE the HVAC module - EATC. REFER to MODULE CONFIGURATION article. If DTC returns, INSTALL a new HVAC module- EATC. REFER to CLIMATE CONTROL article. |
| B2795 | 2795 | Driver Solar Radiation Sensor Circuit Short to Ground | Go to Pinpoint Test B . |
| B2796 | 2796 | Driver Solar Radiation Sensor Circuit Open | Go to Pinpoint Test B . |
| B2956 | 2956 | Servo Motor Left Blend Door Close Line Circuit Failure | Go to Pinpoint Test D . |
| B2957 | 2957 | Servo Motor Left Blend Door Open Line Circuit Failure | Go to Pinpoint Test D . |
| B2958 | 2958 | Servo Motor Vent Open Line Circuit Failure | Go to Pinpoint Test D . |
| B2959 | 2959 | Servo Motor Vent Close Line Circuit Failure | Go to Pinpoint Test D . |
| B2963 | 2963 | Driver Seat Heater Feedback Circuit Fault | REFER to SEATING article. |
| B2964 | 2964 | Passenger Seat Heater Feedback Circuit Fault | REFER to SEATING article. |