Circuit Description
The recirculation actuator is an electronic device that incorporates a stepper motor and feedback potentiometer. The HVAC control module controls the recirculation door position by sending a control signal to the actuator. The signal's value is dependent upon the desired mode selected by the vehicle occupants. As the recirculation actuator moves, the potentiometer produces the actual door position signal that is sent to the HVAC control module. The HVAC control module continues to command the actuator to move until the desired and actual values are equal.
After a calibration or recalibration procedure is performed, the HVAC control module calculates the recirculation actuator travel range. The HVAC control module commands the actuator through it's full range. The HVAC control module stores the learned minimum and maximum position values. The travel range value is calculated by subtracting the minimum and maximum position values. The HVAC control module compares the travel range, minimum and maximum values to calibrated value ranges. If the travel range value is less than or equal to the maximum calibrated limit and greater than or equal to the minimum calibrated limit, then the calibration is considered successful. The HVAC control module continuously compares the actual actuator position to the calibrated minimum and maximum position values.
Conditions for Running the DTC
| • | The ignition is ON. |
| • | Ignition voltage is between 9-16 volts. |
| • | The HVAC control module keep alive memory battery power must be interrupted to run the range check (recalibration procedure). |
Conditions for Setting the DTC
| • | Recirculation actuator position signal is less than 5 counts. |
| • | Recirculation actuator position signal is more than 250 counts. |
| • | The recirculation actuators total travel range (min-max) is less than or greater than the calibrated limits. |
Action Taken When the DTC Sets
| • | The DTC is stored in DTC information. |
| • | The HVAC control module will continue to make use of whatever travel range is still available. |
Conditions for Clearing the DTC
| • | If the HVAC control no longer detects a failure, then the DTC will become history. |
| • | The history DTC will clear after 50 ignition cycles without a failure. |
| • | The DTC can be cleared with a scan tool. |
Diagnostic Aids
| • | A short to voltage on the 5 volt reference circuit of the recirculation actuator will cause DTC B0229 and DTC B0414 to set. |
| • | A damaged or broken recirculation door and or actuator can cause this DTC to set. |
| • | The range fault can only be detected following a check of the actuator travel range. The actuator travel range check (recalibration procedure) can only be initiated by disrupting power to the HVAC control module. |
| • | If none of the above conditions exist then refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. |
Step | Action | Value(s) | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: HVAC Air Delivery/Temperature Control Schematics | ||||||||||
1 | Did you perform the HVAC Diagnostic System Check? | -- | Go to Step 2 | Go to Diagnostic System Check | ||||||
2 |
Does the scan tool indicate that the mode actuator actual parameter changes within the specified range when it is commanded from OSA to REC? | 5-250 counts | Go to Diagnostic Aids | Go to Step 3 | ||||||
3 | Test the recirculation actuator ground circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 4 | ||||||
4 | Test the 5 volt reference circuit of the recirculation actuator for a short to ground or short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 5 | ||||||
5 | Test the 5 volt reference circuit of the temperature actuator for a short to ground or short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 6 | ||||||
6 | Test the recirculation valve position sensor signal circuit for an open, short to ground or short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 9 | Go to Step 7 | ||||||
7 |
Important: The recirculation actuator connector and the HVAC control module connector must be connected to correctly perform this test.
Does the drive shaft of the recirculation actuator rotate and do the counts change? | -- | Go to Step 12 | Go to Step 8 | ||||||
8 | Inspect the recirculation door and the recirculation actuator for the following .
Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 10 | ||||||
9 | Inspect for poor connections at the harness connector of the recirculation actuator. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 11 | ||||||
10 | Inspect for poor connections at the harness connector of the HVAC control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 12 | ||||||
11 | Replace the recirculation actuator. Did you complete the replacement? | -- | Go to Step 13 | -- | ||||||
12 |
Important: Perform the recalibration procedure for the HVAC control module. Replace the HVAC control module. Refer to Control Assembly Replacement . Did you complete the replacement? | -- | Go to Step 13 | -- | ||||||
13 |
Does the DTC reset? | -- | Go to Step 2 | System OK | ||||||
