AB - Headlamps Inoperative
Pinpoint Test AB: Headlamps InoperativeNOTE: Ford DOES NOT provide a procedure to perform the following pinpoint test without the Rotunda New Generation Star (NGS) tester 007-00500 or equivalent.
AB1 - Test Headlamps
- Turn headlamp switch to HEAD position.
Do headlamps and park lamps turn on?
YES Headlamps operating normally. CHECK for for intermittent operation.
NO CHECK bulbs and fuses4 (15A), 6 (10A), 15 (15A) in Town Cars or fuse 6 (15A) in Crown Victoria and Grand Marquis. If bulbs and fuses are good, GO to AB2.
AB2 - Test Headlamps Output
- Connect Rotunda New Generation Star Tester 007-00500 or equivalent to data link connector.
- Command headlamps on.
Do headlamps turn on?
YES GO to AB3.
NO GO to AB4.
AB3 - Test Headlamp Switch
- Request lighting control module PID HDLMPSW.
Does PID indicate switch is in headlamps position?
YES REPLACE lighting control module. RETEST system.
NO SERVICE headlamp switch and circuit 1033 (R/Y). RETEST system.
AB4 - Test High Beam
- Actuate multi-function switch from low to high beam.
Do High beams operate?
YES SERVICE multifunction switch and circuit 13 (R/BK) from multi-function switch to low beams. RETEST system.
NO GO to AB5.
AB5 - Test Low Beam
- Move multi-function switch to low beam.
Do low beams operate?
YES SERVICE multi-function switch and circuit 2 (LG/BK) to high beams. RETEST system.
NO GO to AB6.
AB6 - Test Headlamp Power to Lighting Control Module
- Disconnect connector C3 from lighting control module.
- Check for voltage on pin C3-16.
Is voltage B+?
YES GO to AB7.
NO SERVICE circuit 221 (O/W) from fuse junction panel to lighting control module. RETEST system.
AB7 - Test Headlamps Output
- Using a jumper wire, short lighting control module pin C3-16 to C3-10.
Do headlamps turn on?
YES GO to AB8.
NO SERVICE headlamps output circuit 502 (GY) (Town Car) or circuit 13 (R/BK) (Crown Victoria, Grand Marquis) to multi-function switch or multi-function switch. RETEST system.
AB8 - Test Autolamps
- Set headlamp switch to autolamp position.
- Cover autolamp sensor to simulate darkness.
- Turn ignition switch to RUN.
Do headlamps and autolamp indicator turn on?
YES System operating normally.
NO CHECK fuse 9 (5A) Town Car or fuse 13 (15A) Crown Victoria, Grand Marquis. If fuse is good, GO to AB9. If not, SERVICE supply circuit 218 (W/P) to light sensor amplifier.
AB9 - Test Light Sensor Amplifier
- Connect Rotunda New Generation Star Tester 007-00500 or equivalent to data link connector.
- Request PID ALP_IMP.
Does the PID indicate sensor active?
YES GO to AB10.
NO GO to AB12.
AB10 - Test Autolamp Switch
- Request PID AUTOLMP.
Does the PID indicate switch active?
YES GO to AB11.
NO GO to AB14.
AB11 - Check Ignition Switch
- Request PID IGN_LCM.
Does PID status read RUN?
YES REPLACE lighting control module. RETEST system.
NO SERVICE RUN/START signal circuit 1003 (GY/Y) Town Car or circuit 640 (R/Y) Crown Victoria, Grand Marquis to lighting control module. RETEST system.
AB12 - Check Light Sensor Amplifier Power
- Disconnect connector from light sensor amplifier.
- With ignition switch in RUN, check for voltage at pin 1 circuit 705 (LG/O) Town Car, circuit 640 (R/Y) Crown Victoria, Grand Marquis of light sensor amplifier connector.
Is voltage reading B+?
YES GO to AB13.
NO SERVICE power circuit 705 (LG/O) Town Car or circuit 640 (R/Y) Crown Victoria, Grand Marquis from fuse to light sensor amplifier. RETEST system.
AB13 - Check Circuit 218 (W/P)
- Disconnect connector C2 from lighting control module.
- Check for resistance from pin C2-7 circuit 218 (W/P) of the lighting control module to autolamp sensor pin 3.
Is resistance 5 ohms or less?
YES REPLACE light sensor amplifier. RETEST system.
NO SERVICE circuit 218 (W/P). RETEST system.
AB14 - Check Circuit 220 (P/O)
- Disconnect connector C2 from lighting control module.
- Disconnect connector from headlamp switch.
- Check resistance from pin C2-6 of the lighting control module to pin C2-4 circuit 220 (P/O) headlamp switch.
Is resistance 5 ohms or less?
YES REPLACE headlamp switch. RETEST system.
NO SERVICE circuit 220 (P/O). RETEST system.