LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Cadillac >> 2016 >> XTS Base >> Repair and Diagnosis >> Body & Frame >> Windows >> Fixed And MOVEABLE Window System >> Diagnostic Information and Procedures >> DTC B0283: Rear Defogger Circuit >> Circuit/System Testing
April 5, 2026: LEMON Manuals is launched! Read the announcement.

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 ohm; between the test points:Ground circuit terminal 85 &Ground
    • If 10 ohm; or greater 
    1. Disconnect Ground Connection
    2. Test for less than 2 ohm; between the test points:Ground circuit terminal 85 & Ground Connection
      • If 2 ohm; or greater » Repair the open/high resistance in the circuit.
      • If less than 2 ohm; » Repair the open/high resistance in the ground connection.
    • If less than 10 ohm; 
  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 19 x 2&Ground
      • If less than infinite resistance » Repair the short to ground on the circuit.
      • If infinite resistance
    4. Test for less than 2 ohm; between the test points:Control circuit terminal 86@Relay Socket& Terminal 19 x 2@Control module harness
      • If 2 ohm; or greater » Repair the open/high resistance in the circuit.
      • If less than 2 ohm; » 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
scientia non olet · About LEMON Manuals