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Circuit/System Testing

    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. Remove the component:KR5 Rear Defogger Relay
  3. Test for less than 10 ohms between the test points:Ground circuit terminal 85 & Ground
    • If 10 ohms or greater 
    1. Ground Connection - Disconnect
    2. Test for less than 2 ohms between the test points:Ground circuit terminal 85 & Ground Connection
      • 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.
    • If less than 10 ohms 
  4. Connect a test lamp between the test points:Control circuit terminal 86 & Ground circuit terminal 85
  5. Ignition - On / Vehicle - In Service Mode
  6. Perform the scan tool control function:Rear Defogger - 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:K33 HVAC Control Module
    3. Test for infinite resistance between the test points:Control circuit terminal 86 @Relay Socket & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • If infinite resistance
    4. Test for less than 2 ohms between the test points:Control circuit terminal 86 @Relay Socket & Terminal 19 X2 @Control module harness
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Replace the component:K33 HVAC Control Module
    • If the test lamp is always On 
    1. Ignition/Vehicle - Off & Remove - Test lamp
    2. Disconnect the electrical connector:K33 HVAC Control Module
    3. Ignition - On / Vehicle - In Service Mode
    4. Test for less than 1 V between the test points:Control circuit terminal 86 @Relay Socket & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • If less than 1 V - Replace the component:K33 HVAC Control Module
    • If the test lamp turns On and Off 
  7. Test or replace the component:KR5 Rear Defogger Relay
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