Test D: The Headlamps Are On Continuously

PINPOINT TEST D: THE HEADLAMPS ARE ON CONTINUOUSLY

D1-D5:

D5-D9:

D10-D13:

Normal Operation - Low Beams, Expedition
The smart junction box (SJB) sends reference signals to the headlamp switch through circuits CLF19 (VT/GN), CLF23 (WH/VT), CLF24 (YE/BU) and CLS05 (BU/GY). At any given time, the headlamp switch routes one of the input circuits to ground through circuit GD138 (BK/WH).

When the SJB detects the headlamp switch in the HEADLAMPS ON position and the multifunction switch in the LOW BEAM position, the SJB provides voltage through circuits CLF04 (BN/BU) and CLF05 (BU/GN) to the LH and RH low beam headlamps, respectively.

Normal Operation - Low Beams, Navigator
The SJB sends reference signals to the headlamp switch through circuits CLF19 (VT/GN), CLF23 (WH/VT), CLF24 (YE/BU) and CLS05 (BU/GY). At any given time, the headlamp switch routes one of the input circuits to ground through circuit GD138 (BK/WH).

When the SJB detects the headlamp switch in the HEADLAMPS ON position and the multifunction switch in the LOW BEAM position, the SJB provides voltage through circuits CLF04 (BN/BU) and CLF05 (BU/GN) to the LH and RH high intensity discharge (HID) relay coils, respectively. When the relays are energized, voltage is routed to the LH and RH headlamps through circuits CLF30 (VT/BN) and CLF31 (YE/GY), respectively.

Normal Operation - High Beam Headlamps
The SJB sends a reference signal to the multifunction switch through circuits CLF02 (GY/BN) and CLF27 (GN/BN). When the multifunction switch is placed in the FLASH-TO-PASS or HIGH BEAM position, the voltage signal is routed to ground. When the SJB detects a request for flash-to-pass or high beams (when the low beams are on), the SJB energizes the high beam relay (integral to the SJB), which routes voltage through circuit CLF08 (YE/VT) to the headlamps (and flash-to-pass lamps for Navigator).

DTC B1472 - is an on-demand DTC that sets when the SJB detects the headlamps on input circuit is short to ground.

DTC B1510 - is an on-demand DTC that sets when the SJB detects the flash-to-pass request input circuit is short to ground.

DTC B1696 - is an on-demand DTC that sets when the SJB detects the autolamps on request input circuit is short to ground.

DTC B2A22 - is an on-demand DTC that sets when the SJB detects an open from the headlamp switch off circuit.

DTC B2A23 - is an on-demand DTC that sets when the SJB detects a short to ground on the high beam request input circuit.

DTC B2A2E - is an on-demand DTC that sets when the SJB detects a short to voltage from the RH low beam output circuit.

DTC B2A30 - is an on-demand DTC that sets when the SJB detects a short to voltage from the LH low beam output circuit.

Possible Causes
- Circuit CLF02 (GY/BN) short to ground
- Circuit CLF04 (BN/BU) short to voltage
- Circuit CLF05 (BU/GN) short to voltage
- Circuit CLF08 (YE/VT) short to voltage
- Circuit CLF19 (VT/GN) open or short to ground
- Circuit CLF23 (WH/VT) open
- Circuit CLF24 (YE/BU) short to ground
- Circuit CLF27 (GN/BN) short to ground
- Circuit CLF30 (VT/BN) short to voltage
- Circuit CLF31 (YE/GY) short to voltage
- Circuit CLS05 (BU/GY) open
- Circuit GD138 (BK/WH) open
- HID relay
- Multifunction switch
- Headlamp switch
- SJB