DESCRIPTION
The autolamp system provides automatic on-off control of the headlights in addition to normal headlight switch operation. The system includes a delay feature which keeps the headlights on for a pre-selected time period after ignition is turned off. Major components of the system are a photocell/amplifier assembly, a headlight control relay, and an on-off switch with an integral time delay control (potentiometer).
OPERATION
The headlight switch must be in the OFF position and the autolamp control switch must be in the ON position for automatic operation. The photocell must be exposed to ambient light to operate properly. Time delay can be varied up to 4 1/2 minutes before lights turn off automatically. Turning autolamp control switch away from OFF position increases time headlights are on after ignition is turned off.
PHOTOCELL/AMPLIFIER
The Photocell/amplifier assembly (located below defroster grill) is equipped with an adjustment screw, which is marked with directions and amount of rotation required to reset system to turn on earlier or later than manufacturer setting.
TESTING & DIAGNOSIS
Note. Refer to WIRING DIAGRAMS section for connector terminal ID
SYSTEM OPERATIONAL CHECK
Note. When cause of system malfunction is unknown, perform following procedure to isolate problem.
- Ensure lens of photocell/amplifier assembly is clean and unobstructed. Ensure a clean, tight ground connection exists for circuit No. 57 (Black wire) of autolamp control switch. Ensure autolamp relay connector is properly attached to relay.
- Set autolamp control switch to OFF position. Turn headlights on with headlight switch. If lights do not operate, check and correct standard headlight circuit.
- If standard headlights work okay, check autolamp fuse. See AUTOLAMP FUSE LOCATION table. If fuse is okay, check power and ground circuits. See WIRING DIAGRAMS section. If power and ground circuits are okay, test relay and control switch.
| Application | Location & No. |
|---|---|
| Crown Victoria & Grand Marquis | Inst. Panel Fuse Panel - No. 13 |
AUTOLAMP FUSE LOCATION
AUTOLAMP RELAY TEST
- Locate and remove autolamp relay. See AUTOLAMP RELAY LOCATION table. Using a DVOM, check for continuity between terminals "D" and "E", and terminals "B" and "C" on relay. (Scheme 1) If continuity does not exist, go to next step. If continuity does exist, replace relay.
- Apply battery voltage to terminal "A" and ground terminal "F". With battery power applied, check for continuity between terminals "D" and "E", and terminals "B" and "C" on relay. (Scheme 1) If continuity does not exist, replace relay. If continuity does exist, relay is okay.
Scheme 1
| Application | Location |
|---|---|
| Crown Victoria & Grand Marquis | Behind Center Of Instrument Panel |
AUTOLAMP RELAY LOCATION
On-Off Function
Unplug connector from control switch. Connect ohmmeter leads to Purple/Orange wire and Black wire terminals on switch. Set control switch to full ON position. If continuity does not exist, replace autolamp control switch. If resistance is less than 5.0 ohms, go to next step.
Time Delay Function
With autolamp control switch connector unplugged, connect ohmmeter leads to Black wire and Dark Blue/Orange wire terminals on switch. Check resistance of switch while operating delay function. Resistance should steadily change between 3000-200,000 ohms. If switch does not function properly replace switch.
REMOVAL & INSTALLATION
| CAUTION | When battery is disconnected, vehicle computer and memory systems may lose memory data. Driveability problems may exist until computer systems have completed a relearn cycle. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION before disconnecting battery. |
See AUTOLAMP RELAY LOCATION table under TESTING & DIAGNOSIS. Disconnect battery ground cable. Remove retaining screws. Unplug connector. Remove relay. To install, reverse removal procedure.
Light sensor/amplifier assembly is located behind upper left of instrument panel. Remove defroster grille panel. Remove retaining screws and light sensor/amplifier. Unplug electrical connector. To install, reverse removal procedure.
AUTOLAMP SWITCH
Note. Autolamp switch is serviced from front of instrument panel.
Autolamp control switch is part of headlight switch. Disconnect battery ground cable. Remove headlight switch knob. Remove headlight switch trim (if necessary). Remove retaining screws and headlight switch. Unplug connector. To install, reverse removal procedure.
WIRING DIAGRAM
For Autolamp System wiring diagrams, see WIRING DIAGRAMS section.
See also:
• COMPUTER RELEARN PROCEDURES