Inspection Procedure A-5: One of the headlamps does not illuminate.


caution If the discharge type headlamps do not illuminate, fully understand the precautions in "Service precautions for discharge headlamp" before proceeding with the troubleshooting. Refer to .

COMMENTS ON TROUBLE SYMPTOM



PROBABLE CAUSES



  • Malfunction of the headlamp bulbs
  • Malfunction of the headlamp assembly
  • Damaged harness wires and connectors

DIAGNOSIS PROCEDURE


STEP 1. Check a trouble spot.


Q. Which headlamp (LO or HI) does not illuminate?





STEP 2. Connector check: A-61 <Halogen headlamp (RH)>, A-43 <Halogen headlamp (LH)>, A-62 <Discharge headlamp (RH)>, A-42 <Discharge headlamp (LH)> headlamp assembly connector.


Q. Is the check result normal?





STEP 3. Bulb check



note If discharge-type lower beam headlamps do not illuminate, their bulbs cannot be inspected. In this case, assume the bulbs to be normal and proceed with steps.

Q. Is the check result normal?





STEP 4. Resistance measurement at the A-61 <Halogen headlamp (RH)>, A-43 <Halogen headlamp (LH)>, A-62 <Discharge headlamp (RH)>, A-42 <Discharge headlamp (LH)> headlamp assembly connector.


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Measure the resistance between the connector of lamp which does not illuminate and the body earth.

  • Measure the resistance between the A-61 <Halogen headlamp (RH)>, A-43 <Halogen headlamp (LH)> headlamp assembly connector terminal No. 4 and the body earth. <Halogen headlamp>
  • Measure the resistance between the A-62 <Discharge headlamp (RH)>, A-42 <Discharge headlamp (LH)> headlamp assembly connector terminal No. 6 and the body earth. <Discharge headlamp>
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?





STEP 5. Check the following wiring harness




  • Wiring harness from A-61 headlamp assembly (RH) connector terminal No. 4 to the body earth. <Halogen headlamp (RH)>
  • Wiring harness from A-43 headlamp assembly (LH) connector terminal No. 4 to the body earth. <Halogen headlamp (LH)>
  • Wiring harness from A-62 headlamp assembly (RH) connector terminal No. 6 to the body earth. <Discharge headlamp (RH)>
  • Wiring harness from A-42 headlamp assembly (LH) connector terminal No. 6 to the body earth. <Discharge headlamp (LH)>

Q. Is the check result normal?





STEP 6. Check the following wiring harness




  • Wiring harness from A-61 headlamp assembly (RH) connector terminal No. 2 to the A-32X headlamp relay (LO) connector terminal No. 3. <Halogen headlamp (RH)>
  • Wiring harness from A-43 headlamp assembly (LH) connector terminal No. 2 to the A-32X headlamp relay (LO) connector terminal No. 3. <Halogen headlamp (LH)>
  • Wiring harness from A-62 headlamp assembly (RH) connector terminal No. 5 to the A-32X headlamp relay (LO) connector terminal No. 3. <Discharge headlamp (RH)>
  • Wiring harness from A-42 headlamp assembly (LH) connector terminal No. 5 to the A-32X headlamp relay (LO) connector terminal No. 3. <Discharge headlamp (LH)>

Q. Is the check result normal?





STEP 7. Connector check: A-61 (RH), A-43 (LH) headlamp assembly connector.


Q. Is the check result normal?





STEP 8. Bulb check



Q. Is the check result normal?





STEP 9. Resistance measurement at the A-61 (RH), A-43 (LH) headlamp assembly connector.


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Measure the resistance between the connector of lamp which does not illuminate and the body earth.

  • Measure the resistance between the A-61 (RH), A-43 (LH) headlamp assembly connector terminal No. 4 and the body earth.
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?





STEP 10. Check the following wiring harness




  • Wiring harness from A-61 headlamp assembly (RH) connector terminal No. 4 to the body earth.
  • Wiring harness from A-43 headlamp assembly (LH) connector terminal No. 4 to the body earth.

Q. Is the check result normal?





STEP 11. Check the following wiring harness




  • Wiring harness from A-61 headlamp assembly (RH) connector terminal No. 7 to the A-24X headlamp relay (HI) connector terminal No. 3.
  • Wiring harness from A-43 headlamp assembly (LH) connector terminal No. 7 to the A-24X headlamp relay (HI) connector terminal No. 3.

Q. Is the check result normal?