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Circuit/System Testing

WARNING: This page is about a different car, the 2019 Chevrolet Malibu. However, it is still accessible from the selected car via links, so may be relevant.

Test 1

    NOTE:

    It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.

  1. Ignition/Vehicle & All vehicle systems - Off
  2. Disconnect the electrical connector:S30 Headlamp Switch
  3. Test for less than 10 ohms between the test points:Ground circuit terminal 8 & Ground
    • If 10 ohms or greater 
    1. Test for less than 2 ohms between the test points:Ground circuit terminal 8 @ Component harness & The other end of the circuit
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Repair the open/high resistance in the ground connection.
    • Go to next step: If less than 10 ohms 
  4. Ignition - On / Vehicle - In Service Mode
  5. Verify the scan tool parameter:Automatic Headlamps Disable Switch = Inactive
    • If not the specified state 
    1. Ignition/Vehicle - Off
    2. Disconnect the electrical connector: x1 @ K9 Body Control Module
    3. Test for infinite resistance between the test points:Signal circuit terminal 3 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • If infinite resistance - Replace the component:K9 Body Control Module
    • Go to next step: If the specified state 
  6. Connect a 3 A fused jumper wire between the test points:Signal circuit terminal 3 & Ground circuit terminal 8
  7. Verify the scan tool parameter:Automatic Headlamps Disable Switch = Active
    • If not the specified state 
    1. Ignition/Vehicle - Off & Remove - Jumper wire(s)
    2. Disconnect the electrical connector:X1 @ K9 Body Control Module
    3. Ignition - On / Vehicle - In Service Mode
    4. Test for less than 1 V between the test points:Signal circuit terminal 3 @ 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 less than 2 ohms between the test points:Signal circuit terminal 3 @ Component harness & Terminal 11 @ 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 
  8. Remove - Jumper Wire
  9. Verify the scan tool parameter:Park Lamps Switch = Inactive
    • If not the specified state 
    1. Ignition/Vehicle - Off
    2. Disconnect the electrical connector:X1 @ K9 Body Control Module
    3. Test for infinite resistance between the test points:Signal circuit terminal 5 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • If infinite resistance - Replace the component:K9 Body Control Module
      • Go to next step: If the specified state 
  10. Connect a 3 A fused jumper wire between the test points:Signal circuit terminal 5 & Ground circuit terminal 8
  11. Verify the scan tool parameter:Park Lamps Switch = Active
    • If not the specified state 
    1. Ignition/Vehicle - Off & Remove - Jumper Wire
    2. Disconnect the electrical connector :x1 @ K9 Body Control Module
    3. Ignition - On / Vehicle - In Service Mode
    4. Test for less than 1 V between the test points:Signal circuit terminal 5 @ 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 less than 2 ohms between the test points:Signal circuit terminal 5 @ Component harness & Terminal 22 @ 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 
  12. Remove - Jumper Wire
  13. Verify the scan tool parameter:Headlamps On Switch = Inactive
    • If not the specified state 
    1. Ignition/Vehicle - Off
    2. Disconnect the electrical connector:X1 @ K9 Body Control Module
    3. Test for infinite resistance between the test points:Signal circuit terminal 1 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • If infinite resistance - Replace the component:K9 Body Control Module
      • Go to next step: If the specified state 
  14. Connect a 3 A fused jumper wire between the test points:Signal circuit terminal 1 & Ground circuit terminal 8
  15. Verify the scan tool parameter: = Headlamps On Switch = Active
    • If not the specified state 
    1. Ignition/Vehicle - Off & Remove - Jumper wire(s)
    2. Disconnect the electrical connector:X! @ K9 Body Control Module
    3. Ignition - On / Vehicle - In Service Mode
    4. Test for less than 1 V between the test points:Signal circuit terminal 1 @ 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 less than 2 ohms between the test points:Signal circuit terminal 1 @ Component harness & Terminal 16 @ 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 
  16. Test or replace the component:S30 Headlamp Switch

Test 2

  1. Ignition/Vehicle & All vehicle systems - Off
  2. Disconnect the electrical connector:S78 Turn Signal/Multifunction Switch
    3. NOTE:

    It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.

  3. Test for less than 15 ohms between the test points:Ground circuit terminal 3 & Ground
    • If 15 ohms or greater 
    1. Test for less than 2 ohms between the test points:Ground circuit terminal 3 & Ground terminal
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Repair the open/high resistance in the ground connection.
    • Go to next step: If less than 15 ohms 
  4. Ignition - On / Vehicle - In Service Mode
  5. Verify the scan tool parameter:High Beam Select Switch = Inactive
    • If not the specified state 
    1. Ignition/Vehicle - Off
    2. Disconnect the electrical connector:X3 @ K9 Body Control Module
    3. Test for infinite resistance between the test points:Signal circuit terminal 7 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • If infinite resistance - Replace the component:K9 Body Control Module
    • Go to next step: If the specified state 
  6. Connect a 3 A fused jumper wire between the test points:Signal circuit terminal 7 & Ground
  7. Verify the scan tool parameter:High Beam Select Switch = Active
    • If not the specified state 
    1. Ignition/Vehicle - Off & Remove - Jumper wire(s)
    2. Disconnect the electrical connector:X3 @ K9 Body Control Module
    3. Ignition - On / Vehicle - In Service Mode
    4. Test for less than 1 V between the test points:Signal 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 less than 2 ohms between the test points:Signal circuit terminal 7 @ Component harness & Signal circuit terminal 11 @ 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 
  8. Verify the scan tool parameter:Headlamps Flash Switch = Inactive
    • If not the specified state 
    1. Ignition/Vehicle - Off
    2. Disconnect the electrical connector:X3 @ K9 Body Control Module
    3. Test for infinite resistance between the test points:Signal circuit terminal 6 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • If infinite resistance - Replace the component:K9 Body Control Module
      • Go to next step: If the specified state 
  9. Connect a 3 A fused jumper wire between the test points:Signal circuit terminal 6 @ Component harness & Ground
  10. Verify the scan tool parameter:Headlamps Flash Switch = Active
    • If not the specified state 
  11. Ignition/Vehicle - Off & Remove - Jumper wire(s)
  12. Disconnect the electrical connector:X3 @ K9 Body Control Module
  13. Ignition - On / Vehicle - In Service Mode
  14. Test for less than 1 V between the test points:Signal circuit terminal 6 @ 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
  15. Ignition/Vehicle - Off
  16. Test for less than 2 ohms between the test points:Signal circuit terminal 6 @ Component harness & Signal circuit terminal 17 @ 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 
  17. Test or replace the component:S78 Turn Signal/Multifunction Switch

Test 3

  1. Ignition/Vehicle & All vehicle systems - Off
  2. Disconnect the electrical connector:X2 @ K9 Body Control Module
  3. Test for infinite resistance between the test points:Signal circuit terminal 18 & Ground
    • If less than infinite resistance 
    1. Ignition/Vehicle - Off
    2. Disconnect the electrical connector:S78 Turn Signal/Multifunction Switch
    3. Test for infinite resistance between the test points:Signal circuit terminal 18 @ Control module harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • If infinite resistance - Replace the component:S78 Turn Signal/Multifunction Switch
    • Go to next step: If infinite resistance 
  4. Press and hold the switch:Automatic High Beam Switch @ S78 Turn Signal/Multifunction Switch

    Test for less than 15 ohms between the test points:Signal circuit terminal 18 & Ground

    • If 15 ohms or greater 
    1. Ignition/Vehicle - Off
    2. Disconnect the electrical connector:S78 Turn Signal/Multifunction Switch
    3. Test for less than 2 ohms between the test points:Signal circuit terminal 18 @ Control module harness & Signal circuit terminal 4Component harness
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Replace the component:S78 Turn Signal/Multifunction Switch
    • Go to next step: If less than 15 ohms 
  5. Operate the component: - S78 Turn Signal/Multifunction Switch - Automatic High Beam Switch - On and Off

    Verify the component turns On and Off:Automatic High Beam Activation Status - Indicators @ P16 Instrument Cluster

    • If the component does not activate 

      Replace the component:K9 Body Control Module

    • Go to next step: If the component activates 
  6. All OK.

Test 4

    NOTE:

    It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.

  1. Ignition/Vehicle & All vehicle systems - Off
  2. Disconnect the appropriate electrical connector:
    • X110 @ E13LA Headlamp Assembly - Left
    • X120 @ E13RA Headlamp Assembly - Right
  3. Test for less than 15 ohms between the test points:Ground circuit terminal 5 & Ground
    • If 15 ohms or greater 
    1. Test for less than 2 ohms between the test points:Ground circuit terminal 5 & Ground terminal
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Repair the open/high resistance in the ground connection.
    • Go to next step: If less than 15 ohms 
  4. Connect a test lamp between the test points:Control circuit terminal 6 & Ground
  5. Perform the scan tool control function:Low Beam Lamps - On and Off

    Verify the test lamp turns On and Off.

    • If the test lamp is always Off 
    1. Ignition/Vehicle - Off & Remove - Test lamp
    2. Disconnect the electrical connector:X4 @ K9 Body Control Module
    3. Test for infinite resistance between the test points:Control circuit terminal 6 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    4. Test for less than 2 ohms between the test points:Control circuit terminal 6 @ Component harness & Control circuit terminal 2 @ 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 test lamp is always On 
  6. Ignition/Vehicle - Off & Remove - Test lamp
  7. Disconnect the electrical connector:X4 @ K9 Body Control Module
  8. Ignition - On / Vehicle - In Service Mode
  9. Test for less than 1 V between the test points:Control circuit terminal 6 @ Component harness & Ground
    • If 1 V or greater - Repair the short to voltage on the circuit.
    • If less than 1 V - Replace the component:K9 Body Control Module
    • Go to next step: If the test lamp turns On and Off 
  10. Replace the appropriate component:
    • E4G Headlamp - Left Low Beam
    • E4H Headlamp - Right Low Beam

Test 5

  1. Ignition/Vehicle - Off
  2. Disconnect the component:KR49 Headlamp Low Beam Relay
  3. Verify a test lamp turns On between the test points:B+ circuit terminal 85 & Ground
    • If the test lamp does not turn On 

      Replace the component:X50A Fuse Block - Underhood

    • Go to next step: If the test lamp turns On 
  4. Verify a test lamp turns On between the test points:B+ circuit terminal 30 & Ground
    • If the test lamp does not turn On 

      Replace the component:X50A Fuse Block - Underhood

    • Go to next step: If the test lamp turns On 
  5. Connect a test lamp between the test points:Control circuit terminal 86 & B+
  6. Ignition - On / Vehicle - In Service Mode
  7. Perform the scan tool control function:Low Beam Lamps - On and Off

    Verify the test lamp turns On and Off.

    • If the test lamp is always Off 
    1. Ignition/Vehicle - Off & Remove - Test lamp
    2. Disconnect the electrical connector:X5 @ 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 13 @ Control module 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 less than 2 ohms between the test points:Control circuit terminal 13 @ Control module harness & Control circuit terminal 86 @ KR49 Headlamp Low Beam Relay
      • 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 test lamp is always On 
    1. Ignition/Vehicle - Off
    2. Disconnect the electrical connector:X5 @ K9 Body Control Module
    3. Test for infinite resistance between the test points:Control circuit terminal 13 @ Control module harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • If infinite resistance - Replace the component:K9 Body Control Module
    • Go to next step: If the test lamp turns On and Off 
  8. Ignition/Vehicle & All vehicle systems - Off
  9. Connect the component:KR49 Headlamp Low Beam Relay
  10. Disconnect the appropriate electrical connector:
    • X110 @ E13LA Headlamp Assembly - Left
    • X120 @ E13RA Headlamp Assembly - Right
    11. NOTE:

    It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.

  11. Test for less than 15 ohms between the test points:Ground circuit terminal 4 & Ground
    • If 15 ohms or greater 
    1. Test for less than 2 ohms between the test points:Ground circuit terminal 4 & Ground terminal
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Repair the open/high resistance in the ground connection.
    • Go to next step: If less than 15 ohms 
  12. Connect a test lamp between the test points:Control circuit terminal 5 & Ground
  13. Perform the scan tool control function:Low Beam Lamps - On and Off

    Verify the test lamp turns On and Off.

    • If the test lamp is always Off 
    1. Ignition/Vehicle - Off & Remove - Test lamp
    2. Disconnect the component:KR49 Headlamp Low Beam Relay
    3. Test for infinite resistance between the test points:Control circuit terminal 5 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    4. Test for less than 2 ohms between the test points:Control circuit terminal 5 @ Component harness & The other end of the circuit
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Replace the component:KR49 Headlamp Low Beam Relay
    • Go to next step: If the test lamp is always On 
    1. Ignition/Vehicle - Off & Remove - Test lamp
    2. Disconnect the component:KR49 Headlamp Low Beam Relay
    3. Ignition - On / Vehicle - In Service Mode
    4. Test for less than 1 V between the test points:Control circuit terminal 5 @ Component harness & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • If less than 1 V - Replace the component:KR49 Headlamp Low Beam Relay
    • Go to next step: If the test lamp turns On and Off 
  14. Ignition/Vehicle - Off
  15. Replace the appropriate component:
    • T7L Headlamp Ballast - Left
    • T7R Headlamp Ballast - Right
  16. Ignition - On / Vehicle - In Service Mode
  17. Perform the scan tool control function:Low Beam Lamps - On

    Verify the component activates:Headlamp - Low Beam

    • If the component does not activate 

      Replace the appropriate component:

    • E4G Headlamp - Left Low Beam
    • E4H Headlamp - Right Low Beam
    • Go to next step: If the component activates 
  18. All OK.

Test 6

  1. Ignition/Vehicle - Off
  2. Disconnect the electrical connector:X5 @ K9 Body Control Module
  3. Ignition - On / Vehicle - In Service Mode
  4. Test for greater than 11 V between the test points:Control circuit terminal 18 & Ground
    • If less than 11 V 
    1. Ignition/Vehicle - Off
    2. Disconnect the electrical connector:X1 @ X50A Fuse Block - Underhood
    3. Test for infinite resistance between the test points:Control circuit terminal 18 @ Control module harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    4. Test for less than 2 ohms between the test points:Control circuit terminal 18 @ Control module harness & Control circuit terminal L4 @ Component harness
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Replace the component:X50A Fuse Block - Underhood
    • Go to next step: If 11 V or greater 
  5. Connect a 3 A fused jumper wire between the test points:Control circuit terminal 18 & Ground
  6. Remove the component:F59UA
  7. Ignition - On / Vehicle - In Service Mode
  8. Verify a test lamp turns On between the test points:F59UA & Ground
    • If the test lamp does not turn On 
    1. Ignition/Vehicle - Off & Remove - Test lamp
    2. Disconnect the electrical connector:X1 @ X50A Fuse Block - Underhood
    3. Ignition - On / Vehicle - In Service Mode
    4. Test for less than 1 V between the test points:Control circuit terminal 18 @ Control module harness & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • If less than 1 V - Replace the component:X50A Fuse Block - Underhood
    • Go to next step: If the test lamp turns On 
  9. Ignition/Vehicle - Off
  10. Connect the electrical connector:X5 @ K9 Body Control Module
  11. Install the component:F59UA
  12. Ignition/Vehicle & All vehicle systems - Off
  13. Disconnect the appropriate electrical connector:
    • X110 @ E13LA Headlamp Assembly - Left
    • X120 @ E13RA Headlamp Assembly - Right
    14. NOTE:

    It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.

  14. Test for less than 15 ohms between the test points:Ground circuit terminal 5 @ E13 Headlamp Assembly & Ground
    • If 15 ohms or greater 
    1. Test for less than 2 ohms between the test points:
      • { With T4F } X110 - Ground circuit terminal 4 & Ground terminal
      • { With T4F } X120 - Ground circuit terminal 2 & Ground terminal
      • { With T4A } Ground circuit terminal 5 & Ground terminal
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Repair the open/high resistance in the ground connection.
    • Go to next step: If less than 15 ohms 
  15. Connect a test lamp between the test points:
    • { With T4F } Ground circuit terminal 3 & Ground
    • { With T4A } Ground circuit terminal 7 & Ground
  16. Perform the scan tool control function:High Beams - On and Off

    Verify the test lamp turns On and Off.

    • If the test lamp is always Off 
    1. Ignition/Vehicle - Off & Remove - Test lamp
    2. Disconnect the electrical connector:X5 @ X50A Fuse Block - Underhood
    3. Test for infinite resistance between the test points:
      • { With T4F } Ground circuit terminal 3 & Ground
      • { With T4A } Ground circuit terminal 7 & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    4. Test for less than 2 ohms between the test points:Control circuit terminal 7 @ E13 Headlamp Assembly & Control circuit terminal L8 X5 @ X50A Fuse Block - Underhood
      • { With T4F } Ground circuit terminal 3 @ Component harness & Control circuit terminal L8 X5 @ X50A Fuse Block - Underhood
      • { With T4A } Ground circuit terminal 7 @ Component harness & Control circuit terminal L8 X5 @ X50A Fuse Block - Underhood
      • 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
    • If the test lamp is always On 
    1. Ignition/Vehicle - Off & Remove - Test lamp
    2. Disconnect the electrical connector:X5 @ X50A Fuse Block - Underhood
    3. Ignition - On / Vehicle - In Service Mode
    4. Test for less than 1 V between the test points:
      • { With T4F } Ground circuit terminal 3 & Ground
      • { With T4A } Ground circuit terminal 7 & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • If less than 1 V - Replace the component:K9 Body Control Module
      • Go to next step: If the test lamp turns On and Off 
  17. Replace the appropriate component:
    • E13LA Headlamp Assembly - Left
    • E13RA Headlamp Assembly - Right
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