2010 Cadillac CTS Sedan AWD V6-3.6L Page 627
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the Air Quality Sensor.
2. Test for less than 5 ohm between the ground circuit terminal 2 and ground.
瀚慖f greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 1 and ground.
瀚慖f the test lamp does not illuminate, test the ignition circuit for a short to ground or a open/high resistance.
4. Ignition ON, test for 4.8-5.2 volts between the signal circuit terminal 3 and ground.
瀚慖f less than the specified range, test the signal 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 signal circuit for a short to voltage. If the circuit tests normal, replace the HVAC control
module.
5. If all circuits test normal, replace the Air Quality Sensor.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Ambient Air Quality Sensor Replacement (See: Heating and Air Conditioning/Ambient Temperature Sensor / Switch HVAC/Service and
Repair/Ambient Air Quality Sensor Replacement)
* Control Module References (See: Testing and Inspection/Programming and Relearning) for HVAC Control Module replacement, setup, and
programming
Without UHA/UHF
DTC B3849 (Without UHA/UHF)
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC B3849 00
- Exterior Door Handle Switch Circuit
Diagnostic Fault Information
Circuit/System Description
The exterior door handle switch signal circuit provides inputs to their respective door lock/window switch when the exterior door handle switch is
activated. This input allows the door lock/window switch to detect a door open request. The door lock/window switch provides voltage to the
exterior door handle switch via the front door handle switch signal circuit. When the front door handle is activated, the switch closes and the
voltage signals from the door lock/window switch are pulled to ground.
