LEMON Manuals: Even more car manuals for everyone
Home >> Cadillac >> 2021 >> CT4 Sport, 4WD >> Repair and Diagnosis >> External Pages >> Different car >> Section 228 (Vehicle Access System - Diagnostic Information And Procedures) >> Diagnostic Information and Procedures >> Power Door Child Lock Malfunction >> Circuit/System Testing

Circuit/System Testing

WARNING: This page is about a different car, the 2022 Cadillac CT4. However, it is still accessible from the selected car via links, so may be relevant.

Test 1

  1. Ignition/Vehicle & All vehicle systems - Off
  2. Disconnect the electrical connector: A23LR Rear Side Door Latch - Left
  3. Ignition ON.
  4. Test for greater than 7 V between the signal circuit terminal 2 and ground.
    • If 7 V or less 
    1. Ignition OFF, disconnect the harness connector at the K9 Body 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.
      • Go to next step: 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 K9 Body Control Module
    • Go to next step: If greater than 7 V 
  5. Connect a test lamp between the test points: Control circuit terminal 9 & Ground
  6. Operate the component: child lock switch - Pressed - On and Off

    Verify the test lamp state:

    Not Used = Test lamp always OFF

    Child lock switch - Pressed - On and Off = Test lamp flashes ON and OFF

    • If not the specified state 
    1. Ignition/Vehicle - Off & Remove - Test lamp
    2. Disconnect the electrical connector: X7 @ K9 Body Control Module
    3. Ignition - On/Vehicle - In Service Mode
    4. Test for less than 1 V between the test points: Control circuit terminal 9 @ Component harness & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • Go to next step: If less than 1 V
    5. Ignition/Vehicle - Off
    6. Test for infinite resistance between the test points: Control circuit terminal 9 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    7. Test for less than 2 ohms between the test points: Control circuit terminal 9 @ Component harness & Terminal 3 X7 @ Control module harness
    • If 2 ohms or greater - Repair the open/high resistance in the circuit.
    • If less than 2 ohms - Replace the component: K9 Body Control Module
    • Go to next step: If the specified state 
  7. Test or replace the component: A23LR Rear Side Door Latch - Left

Test 2

  1. Ignition/Vehicle & All vehicle systems - Off
  2. Disconnect the electrical connector: A23RR Rear Side Door Latch - Right
  3. Ignition ON.
  4. Test for greater than 7 V between the signal circuit terminal 4 and ground.
    • If 7 V or less 
    1. Ignition OFF, disconnect the harness connector at the K9 Body 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.
      • Go to next step: 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 K9 Body Control Module
    • Go to next step: If greater than 7 V 
  5. Connect a test lamp between the test points: Control circuit terminal 7 & Ground
  6. Operate the component: child lock switch - Pressed - On and Off

    Verify the test lamp state:

    Not Used = Test lamp always OFF

    Child lock switch - Pressed - On and Off = Test lamp flashes ON and OFF

    • If not the specified state 
    1. Ignition/Vehicle - Off & Remove - Test lamp
    2. Disconnect the electrical connector: X7 @ K9 Body Control Module
    3. Ignition - On/Vehicle - In Service Mode
    4. Test for less than 1 V between the test points: Control circuit terminal 7 @ Component harness & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • Go to next step: If less than 1 V
    5. Ignition/Vehicle - Off
    6. Test for infinite resistance between the test points: Control circuit terminal 7 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    7. Test for less than 2 ohms between the test points: Control circuit terminal 7 @ Component harness & Terminal 3 X7 @ Control module harness
    • If 2 ohms or greater - Repair the open/high resistance in the circuit.
    • If less than 2 ohms - Replace the component: K9 Body Control Module
    • Go to next step: If the specified state 
  7. Test or replace the component: A23RR Rear Side Door Latch - Right
scientia non olet · About LEMON Manuals