Circuit/System Testing

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Ignition OFF, disconnect the harness connector at the S48A Multifunction Switch - Instrument Panel, ignition ON.
Verify a test lamp illuminates between the control circuit terminal 5 and ground.
- If the test lamp does not illuminate
1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module.
2. Test for less than 2 Ω in the control circuit end to end.
  - If 2 Ω or greater, repair the open/high resistance in the circuit.
  - If less than 2 Ω, refer to Interior Backlighting Malfunction .
- If the test lamp illuminates
Ignition OFF, connect the harness connector at the S48A Multifunction Switch - Instrument Panel. Disconnect the X1 harness connector at the B174W Frontview Camera - Windshield, ignition ON.
Verify the lane departure warning switch indicator is not illuminated.
- If the lane departure warning switch indicator is illuminated
1. Ignition OFF, disconnect the harness connector at the S48A Multifunction Switch - Instrument Panel.
2. Test for infinite resistance between the S48A Multifunction Switch - Instrument Panel control circuit terminal 6 and ground.
  - If less than infinite resistance, repair the short to ground in the circuit.
  - If infinite resistance, replace the S48A Multifunction Switch - Instrument Panel.
- If the lane departure warning switch indicator is not illuminated
Connect a 3 A fused jumper wire between the control circuit terminal 4 and ground.
Verify the lane departure warning switch indicator is illuminated.
- If the lane departure warning switch indicator is not illuminated
1. Ignition OFF, disconnect the harness connector at the S48A Multifunction Switch - Instrument Panel.
2. Test for less than 1 V between the control 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 control circuit end to end.
  - If 2 Ω or greater, repair the open/high resistance in the circuit.
  - If less than 2 Ω, replace the S48A Multifunction Switch - Instrument Panel.
- If the lane departure warning switch indicator is illuminated
Replace the B174W Frontview Camera - Windshield.