Headlamp (For USA)

HEADLAMP (FOR USA)

System Description
The control of headlamp system operation is dependent upon the position of the combination switch (lighting switch). When the lighting switch is placed in the 2ND position, BCM (body control module) receives input signal requesting the headlamps (and tail lamps) illuminate. This input signal is communicated to IPDM E/R (intelligent power distribution module engine room) through CAN communication lines. The CPU (central processing unit) located in the IPDM E/R controls headlamp high and headlamp low relay coils. These relays, when energized, direct power to the respective headlamps, which then illuminate.

OUTLINE
Power is supplied at all times
- to headlamp high relay, located in IPDM E/R and
- to headlamp low relay, located in IPDM E/R, from battery direct,
- through 10 A fuse (No. 71, located in IPDM E/R)
- to CPU located in IPDM E/R,
- through 15 A fuse (No. 78, located in IPDM E/R)
- to CPU located in IPDM E/R,
- through 50 A fusible link (letter F, located in fuse, fusible link and relay box)
- to BCM terminal 55,
- through 10 A fuse [No. 18, located in fuse block (J/B)]
- to BCM terminal 42,
- through 10 A fuse [No. 19, located in fuse block (J/B)]
- to combination meter terminal 21.

With the ignition switch in the ON or START position, power is supplied
- through 10 A fuse [No. 1, located in fuse block (J/B)]
- to BCM terminal 38,
- through 10 A fuse [No. 14, located in fuse block (J/B)]
- to combination meter terminal 22 and 23.

With the ignition switch in the ACC or ON position, power is supplied
- through 10 A fuse [No. 6, located in fuse block (J/B)]
- to BCM terminal 11.

Ground is supplied
- to BCM terminal 52
- through grounds M30 and M66,
- to IPDM E/R terminals 38 and 60
- through grounds E17 and E43,
- to combination meter terminals 1, 24 and 25
- through grounds M30 and M66.

HEADLAMP OPERATION

Low Beam Operation
With the lighting switch in 2ND position, the BCM receives input signal requesting headlamps to illuminate. This input signal is communicated to IPDM E/R through CAN communication lines. The CPU located in the IPDM E/R controls headlamp low relay coil, which when energized, directs power
- through 15 A fuse (No. 76, located in IPDM E/R)
- through IPDM E/R terminal 20
- to front combination lamp RH terminal 3,
- through 15 A fuse (No. 86, located in IPDM E/R)
- through IPDM E/R terminal 30
- to front combination lamp LH terminal 3.

Ground is supplied
- to front combination lamp RH terminal 4
- through grounds E17 and E43,
- to front combination lamp LH terminal 4
- through grounds E17 and E43.

With power and ground supplied, low beam headlamps illuminate.

High Beam Operation/Flash-to-Pass Operation
With the lighting switch in 2ND position and placed in HIGH BEAM or PASSING position, the BCM receives input signal requesting the headlamp high beams to illuminate. This input signal is communicated to IPDM E/R through CAN communication lines. The CPU located in the IPDM E/R controls headlamp high relay coil and low relay coil, which when energized, directs power
- through 15 A fuse (No. 76, located in IPDM E/R)
- through IPDM E/R terminal 20
- to front combination lamp RH terminal 3,
- through 15 A fuse (No. 86, located in IPDM E/R)
- through IPDM E/R terminal 30
- to front combination lamp LH terminal 3,
- through 10 A fuse (No. 72, located in IPDM E/R)
- through IPDM E/R terminal 27
- to front combination lamp RH terminal 2,
- through 10 A fuse (No. 74, located in IPDM E/R)
- through IPDM E/R terminal 28
- to front combination lamp LH terminal 2.

Ground is supplied
- to front combination lamp RH terminals 4 and 8
- through grounds E17 and E43,
- to front combination lamp LH terminals 4 and 8
- through grounds E17 and E43.

With power and ground supplied, the high beam and low beam headlamps illuminate.
High beam indicator illuminates when combination meter receives input signal requesting high beam indicator to illuminate. This is communicated to BCM through CAN communication lines.

COMBINATION SWITCH READING FUNCTION
Refer to BCS-3, "COMBINATION SWITCH READING FUNCTION". Description and Operation

EXTERIOR LAMP BATTERY SAVER CONTROL
When the combination switch (lighting switch) is in the 2ND position and the ignition switch is turned from ON or ACC to OFF, the battery saver control function is activated.
Under this condition, the headlamps remain illuminated for 5 minutes, then the headlamps are turned off.
Exterior lamp battery saver control mode can be changed by the function setting of CONSULT-II.

AUTO LIGHT OPERATION (IF EQUIPPED)
Refer to "System Description".

VEHICLE SECURITY SYSTEM
The vehicle security system will flash the high beams if the system is triggered.

XENON HEADLAMP
Xenon type lamps are used for to the low beam headlamps. Xenon bulbs do not use a filament. Instead, they produce light when a high voltage current is passed between two tungsten electrodes through a mixture of xenon (an inert gas) and certain other metal halides. In addition to strong lighting power, electronic control of the power supply gives the headlamps stable quality and tone color.

Followings are some advantages of the xenon type headlamp.
- The light produced by the headlamps is white color similar to sunlight that is easy to the eyes.
- Light output is nearly double that of halogen headlamps, affording increased area of illumination.
- Counter-reflected luminance increases and the contrast enhances on the wet road in the rain. That makes visibility go up more than the increase of the light volume.
- Power consumption is approximately 25 percent less than halogen headlamps, reducing battery load.

CAN Communication System Description
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle multiplex communication line with high data communication speed and excellent error detection ability. Many electronic control units are equipped onto vehicle, and each control unit shares information and links with other control units during operation (not independent). In CAN communication, control units are connected with 2 communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring. Each control unit transmits/receives data but selectively reads required data only.

CAN Communication Unit
Refer to LAN-27, Information Bus. Description and Operation