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Home >> Cadillac >> 2015 >> SRX Base, 4D Utility >> Repair and Diagnosis (Single Page) >> Heating, Ventilation & A/C (HVAC) >> HVAC Control Systems >> HVAC System - Automatic >> Diagnostic Information and Procedures >> DTC B0163, B0183, or B1405: Passenger Compartment Temperature Sensor/Solar Sensor/Module Reference >> Circuit/System Testing
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Circuit/System Testing

Low Reference Test

    NOTE:

    You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

  1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B10B Ambient Light/Sunload Sensor. It may take up to 10 min for all vehicle systems to power down.
    2. NOTE:

    The scan tool must be disconnected from the vehicle before performing the next test.

  2. Test for less than 10 Ω between the low reference circuit terminal 6 and ground.
    • If 10 Ω or greater 
    1. Ignition OFF, disconnect the harness connector at the K33 HVAC Control Module.
    2. Test for less than 2 Ω in the low reference circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K33 HVAC Control Module.
    • If less than 10 Ω 
  3. Test or replace the B10B Ambient Light/Sunload Sensor.

DTC B0163

    NOTE:

    You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

  1. Ignition OFF, disconnect the harness connector at the B10B Ambient Light/Sunload Sensor, ignition ON.
  2. Verify the scan tool Passenger Compartment Air Temperature (Unfiltered) parameter is less than -37°C (-35°F).
    • If -37°C (-35°F) or greater 
    1. Ignition OFF, disconnect the harness connectors X1 and X2 at the K33 HVAC Control Module.
    2. Test for infinite resistance between the signal circuit terminal 3 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the K33 HVAC Control Module.
    • If less than -37°C (-35°F) 
  3. Test for 4.8-5.2 V between the signal circuit terminal 3 and ground.
    • If less than 4.8 V 
    1. Ignition OFF, disconnect the harness connector at the K33 HVAC Control Module.
    2. Test for infinite resistance between the signal circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in the signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K33 HVAC Control Module.
    • If greater than for 5.2 V 
    1. Ignition OFF, disconnect the harness connector at the K33 HVAC Control Module, ignition ON.
    2. Test for less than 1 V between the signal circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K33 HVAC Control Module.
    • If between 4.8-5.2 V 
  4. Install a 3 A fused jumper wire between the signal circuit terminal 3 and the low reference circuit terminal 6.
  5. Verify the scan tool parameter Passenger Compartment Air Temperature (Unfiltered) parameter is greater than 78°C (172°F).
    • If 78°C (172°F) or less 
    1. Ignition OFF, remove the jumper wire and disconnect the harness connectors X1 and X2 at the K33 HVAC Control Module, ignition ON.
    2. Test for less than 1 V between the signal circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V
    3. Ignition OFF.
    4. Test for less than 2 Ω in the signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K33 HVAC Control Module.
    • If greater than 78°C (172°F) 
  6. Test or replace the B10B Ambient Light/Sunload Sensor.

DTC B0183

    NOTE:

    You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

  1. Ignition OFF, disconnect the harness connector at the B10B Ambient Light/Sunload Sensor, ignition ON.
  2. Test for 4.8-5.2 V between the signal circuit terminal 4 and ground.
    • If less than 4.8 V 
    1. Ignition OFF, disconnect the harness connector at the K33 HVAC Control Module.
    2. Test for infinite resistance between the signal circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in the signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K33 HVAC Control Module.
    • If greater than for 5.2 V 
    1. Ignition OFF, disconnect the harness connector at the K33 HVAC Control Module, ignition ON.
    2. Test for less than 1 V between the signal circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K33 HVAC Control Module.
    • If between 4.8-5.2 V 
  3. Test or replace the B10B Ambient Light/Sunload Sensor.
  4. Verify DTC B0183 did not reset.
    • If DTC B0183 reset 

      Replace the K33 HVAC Control Module.

    • If DTC B0183 did not reset 
  5. All OK.

DTC B1405

    NOTE:

    You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

  1. Ignition OFF, disconnect the harness connector at the B10B Ambient Light/Sunload Sensor, ignition ON.
  2. Test for greater than 10 V between signal circuit terminal 2 and ground.
    • If less than 10 V 
    1. Ignition OFF, disconnect the harness connector at the K33 HVAC Control Module.
    2. Test for infinite resistance between signal circuit terminal 2 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in the signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K33 HVAC Control Module.
    • If 10 V or greater 
  3. Ignition OFF, disconnect the harness connector at the K33 HVAC Control Module, ignition ON.
  4. Test for less than 1 V between the signal circuit terminal 2 and ground.
    • If 1 V or greater 

      Repair the short to voltage on the circuit.

    • If less than 1 V 
  5. Test or replace the B10B Ambient Light/Sunload Sensor.
  6. Verify DTC B1405 did not reset.
    • If DTC B1405 reset 

      Replace the K33 HVAC Control Module.

    • If DTC B1405 did not reset 
  7. All OK.
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