2010 Cadillac CTS Sedan AWD V6-3.6L Page 225
* The DTC becomes history when the HVAC control module no longer detects the condition that set the DTC.
* The history DTC will clear after 50 fault-free ignition cycles.
Reference Information
Schematic Reference
HVAC Schematics (See: Heating and Air Conditioning/Diagrams/Electrical Diagrams)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Description and Operation
Automatic HVAC Description and Operation (See: Heating and Air Conditioning/Description and Operation/HVAC - Automatic)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit
Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/Wiring Repairs/Wiring Repairs)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
Circuit/System Verification
Ignition ON, command the appropriate actuator to 100 percent with a scan tool. The scan tool should display between 224 and 230 counts on the
mode actuator, all other actuators should display between 199 and 205 counts.
Circuit/System Testing
1. Ignition OFF, disconnect the X1 harness connector at the HVAC control module.
2. Ignition ON, Verify that a test lamp illuminates between the B+ circuit terminal 18 and ground.
瀚慖f the test lamp does not illuminate, test the B+ circuit for an short to ground or a open/high resistance.
3. Ignition OFF, connect the harness connector at the HVAC control module and disconnect the harness connector at the appropriate actuator.
4. Ignition OFF, test for less than 10 ohms between the following low reference circuit terminal and ground.
* Air temperature actuator-left terminal 1
* Air temperature actuator-right terminal 2
* Mode actuator terminal 2
* Recirculation actuator terminal 1
瀚慖f greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the HVAC
control module.
5. Ignition ON, test for 4.8-5.2 volts between the following 5-volt reference circuit terminal and ground.
* Air temperature actuator-left terminal 2
* Air temperature actuator-right terminal 1
* Mode actuator terminal 1
* Recirculation actuator terminal 3
瀚慖f less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal,
replace the HVAC control module.
瀚慖f greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the HVAC
control module.
6. Verify the scan tool Door Position parameter is greater than 250 counts.
瀚慖f less than the specified range, test the following signal circuit for a short to ground. If the circuit tests normal, replace the HVAC control
module.
* Air temperature actuator-left terminal 3
* Air temperature actuator-right terminal 3
* Mode actuator terminal 3
* Recirculation actuator terminal 5
