LEMON Manuals: Even more car manuals for everyone
Home >> Buick >> 1997 >> Park Avenue Ultra >> Repair and Diagnosis >> Accessories & Equipment >> Headlights - Automatic Twilight Sentinel >> Diagnosis & Testing >> Headlight System Tests >> Low Beam Headlights Inoperative

Low Beam Headlights Inoperative

  1. If diagnostic system check was performed, go to next step. If diagnostic system check was not performed, go to DIAGNOSTIC SYSTEM CHECK.
  2. Disconnect LCM 7-pin connector C1. Using DVOM, check voltage between LCM connector C1 terminal "G" (Red wire) and ground. If reading is about 12 volts, go to next step. If reading is not about 12 volts, go to step 8).
  3. Disconnect LCM 24-pin connector C2. Check voltage between LCM harness connector C1 terminal "G" (Red wire) and LCM harness connector C2 terminals B4 and B5 (Black/White wires). If reading is about 12 volts, go to next step. If reading is not about 12 volts, go to step 9).
  4. Check voltage between LCM harness connector C1 terminals "G" (Red wire) and "E" (Black wire). If reading is about 12 volts, go to next step. If reading is not about 12 volts, go to step 10).
  5. Disconnect headlight switch connector located at left side of instrument panel. Reconnect LCM connectors C1 and C2. Connect a fused jumper wire between headlight switch harness connector terminal "D" (White wire) and ground. If low beam headlights turn on, go to step 11). If low beam headlights do not turn on, go to next step.
  6. Disconnect LCM 7-pin connector C1. Connect a fused jumper wire between LCM harness connector C1 terminals "G" (Red wire) and "F" (Tan wire). If low beam headlights turn on, go to step 13). If low beam headlights do not turn on, go to next step.
  7. Repair open in circuit No. 12 (Tan wire) between LCM connector C1, instrument panel power distribution block and underhood bussed electrical center. Perform DIAGNOSTIC SYSTEM CHECK.
  8. Repair open or short to ground in circuit No. 1242 (Red wire) between underhood bussed electrical center, instrument panel bussed electrical center and LCM. Perform DIAGNOSTIC SYSTEM CHECK.
  9. Repair open in circuit No. 351 (Black/White wire) between LCM connector C2 and ground. Perform DIAGNOSTIC SYSTEM CHECK.
  10. Repair open in circuit No. 350 (Black wire) between LCM connector C1 and ground. Perform DIAGNOSTIC SYSTEM CHECK.
  11. Repair open in circuit No. 351 (Black/White wire) between headlight switch and ground. If circuit is okay, go to next step. If circuit is not okay, go to step 15).
  12. Replace headlight switch. Perform DIAGNOSTIC SYSTEM CHECK.
  13. Check for open in circuit No. 103 (White wire) between headlight switch and LCM connector C2. If circuit is okay, go to next step. If circuit is not okay, go to step 15).
  14. Replace LCM. See REMOVAL & INSTALLATION  . Perform DIAGNOSTIC SYSTEM CHECK.
  15. Repair open in appropriate wire. Perform DIAGNOSTIC SYSTEM CHECK.
scientia non olet · About LEMON Manuals