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Exterior Lights Test 2A - Auto Headlights Inoperative

NOTE: Perform EXTERIOR LIGHTS TEST 1A  before proceeding. For connector terminal ID, see CONNECTOR IDENTIFICATION  and WIRING DIAGRAM. Perform TEST VER-1A  after each repair.
CAUTION: Always turn ignition switch to OFF position prior to disconnecting any module connector. Ensure all connectors are clean and tight.
  1. Using scan tool, select BODY COMPUTER SYSTEM TEST, then PCM MONITOR. If scan tool does not displays PCM ACTIVE ON THE BUS, go to TEST 9A  under VEHICLE COMMUNICATIONS. If scan tool displays PCM ACTIVE ON THE BUS, go to next step.
  2. Using scan tool, actuate headlight relay. If headlights do not illuminate, go to step 5). If headlights illuminate, turn headlight switch to AUTO. If scan tool displays ENABLED, go to next step. If scan tool does not display ENABLED, go to step 11).
  3. Disconnect auto headlight sensor. Auto headlight sensor is located on center of defroster grille, at base of windshield. Ensure headlight switch is in AUTO position. Start engine. If headlights illuminate, replace auto headlight sensor. If headlights do not illuminate, go to next step.
  4. Turn engine off. Disconnect Body Control Module (BCM) White 24-pin connector. BCM is located under left side of dash. Using scan tool in ohmmeter mode, probe auto headlight sensor connector terminal No. 4 (Orange/Black wire). If resistance is less than 500 ohms, repair short to ground in Orange/Black wire. If resistance is 500 ohms or more, replace BCM.
  5. Remove headlight relay. Headlight relay is located in junction block, behind right kick panel. Using scan tool in voltmeter mode, probe headlight relay connector terminal No. 30 (Red/Light Blue wire). See Figure .
  6. If voltage is less than 10 volts, repair open in Red/Light Blue wire between headlight relay connector terminal No. 30 and power distribution center. Power distribution center is located in engine compartment. If voltage is 10 volts or more, go to next step.
  7. Using scan tool in voltmeter mode, probe headlight relay connector terminal No. 86 (Red/Light Blue wire). If voltage is less than 10 volts, repair open in Red/Light Blue wire between headlight relay connector terminal No. 86 and power distribution center. If voltage is 10 volts or more, go to next step.
  8. Turn headlights on. Using scan tool in voltmeter mode, probe headlight relay connector terminal No. 87 (Tan/Black wire). If voltage is less than 10 volts, repair open in Tan/Black wire between headlight relay and headlight switch. If voltage is 10 volts or more, go to next step.
  9. Connect a test light between headlight relay connector terminals No. 85 (Black/Orange wire) and No. 86 (Red/Light Blue wire). Using scan tool, actuate headlight relay. If test light illuminates when headlight relay is actuated, replace headlight relay. If test light does not illuminate when headlight relay is actuated, go to next step.
  10. Stop actuating headlight relay. Connect a jumper wire between headlight relay connector terminal No. 85 (Black/Orange wire) and chassis ground. Disconnect BCM White 24-pin connector. Using scan tool in ohmmeter mode, probe BCM White 24-pin connector terminal No. 12 (Black/Orange wire). If resistance is more than 5 ohms, repair open in Black/Orange wire. If resistance is 5 ohms or less, replace BCM.
  11. Disconnect headlight switch connector. Using scan tool in voltmeter mode, probe headlight switch connector terminal No. 13 (Light Blue/Red wire). If voltage is less than 10 volts, go to step 15). If voltage is 10 volts or more, go to next step.
  12. Connect a jumper wire between headlight switch connector terminal No. 13 (Light Blue/Red wire) and chassis ground. Using scan tool, read headlight status. If scan tool does not display ENABLED, replace BCM. If scan tool displays ENABLED, go to next step.
  13. Close all doors. Ensure ignition and all lights are off. Using scan tool in ohmmeter mode, probe headlight switch connector terminal No. 5 (Black wire). If resistance is more than 50 ohms, repair open in Black wire. If resistance is 50 ohms or less, go to next step.
  14. Using scan tool in ohmmeter mode, probe headlight switch connector terminal No. 2 (Black wire). If resistance is more than 50 ohms, repair open in Black wire. If resistance is 50 ohms or less, replace headlight switch.
  15. Using scan tool in voltmeter mode, backprobe BCM Black 24-pin connector terminal No. 7 (Light Blue/Red wire). DO NOT  disconnect BCM connector. If voltage is less than 10 volts, replace BCM. If voltage is 10 volts or more, repair open in Light Blue/Red wire.
Fig 1: Identifying Relay Terminals
G95H35292
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