Daytime Running Lamp: Description and Operation
System Description (CANADA)The headlamp system for Canada vehicles contains a daytime light control unit that activates the high beam headlamps at approximately half illumination whenever the engine is running. If the parking brake is applied before the engine is started the daytime lights will not be illuminated. The daytime lights will illuminate once the parking brake is released. Thereafter, the daytime lights will continue to operate when the parking brake is applied.
And battery saver system is controlled by the headlamp battery saver control unit and smart entrance control unit.
Power is supplied at all times
- to headlamp LH relay terminals 1 and 3
- through 15 A fuse (No.60, located in the fuse and fusible link box), and
- to headlamp LH relay terminal 6
- through 20 A fuse (No.32, located in the fuse and fusible link box), and
- to headlamp RH relay terminals 1 and 3
- through 15 A fuse (No.59, located in the fuse and fusible link box), and
- to headlamp RH relay terminal 6
- through 20 A fuse (No.31, located in the fuse and fusible link box), and
- to headlamp battery saver control unit terminal 7, and
- to smart entrance control unit terminal 10
- through 7.5 A fuse [No.24, located in the fuse block (J/B)].
Ground is supplied
- to daytime light control unit terminal 16,
- to auto light control unit terminal 5 and
- to headlamp battery saver control unit terminals 4 and 11.
When the ignition switch is in the ON or START position, power is also supplied
- to daytime light control unit terminal 3,
- to auto light control unit terminal 1,
- to headlamp battery saver control unit terminal 10, and
- to smart entrance control unit terminal 33
- through 7.5 A fuse [No.11, located in the fuse block (J/B)], and
- to headlamp battery saver control unit terminal 1
- through 10 A fuse [No.16, located in the fuse block (J/B)].
When the ignition switch is in the START position, power is supplied
- to daytime light control unit terminal 2
- through 7.5 A fuse [No.26, located in the fuse block (J/B)].
When the ignition switch is in the ACC or ON position, power is supplied
- to auto light control unit terminal 2
- through 10 A fuse [No.9, located in the fuse block (J/B)].
HEADLAMP OPERATION
Power Supply to Low Beam and High Beam
When lighting switch is in 2ND or PASS position, ground is supplied
- to headlamp relay (LH and RH) terminal 2 from headlamp battery saver control unit terminals 2 and 8
- through headlamp battery saver control unit terminal 3 and 9
- from lighting switch terminal 12.
Headlamp relays (LH and RH) are energized.
Low Beam Operation
When the lighting switch is turned to 2ND and LOW ("B") positions, power is supplied
- from terminal 7 of each headlamp relay
- to terminal 3 of each headlamp
Ground is supplied
- to terminal 4 of each headlamp
- through body grounds E13 and E41.
With power and ground supplied, the low beam headlamps illuminate.
High Beam Operation Flash-to-pass Operation
When the lighting switch is turned to 2ND and HIGH ("A") or PASS ("C") positions, power is Supplied
- to terminal 1 of headlamp LH
- through daytime light control unit terminals 6 and 5
- from headlamp LH relay terminal 5
- to terminal 1 of headlamp RH
- through daytime light control unit terminals 7 and 4
- from headlamp RH relay terminal 5, and
- to combination meter terminal 26 for HIGH BEAM indicator
- from headlamp LH relay terminal 5.
Ground is supplied
- to terminal 2 of LH headlamp
- through daytime light control unit terminals 10 and 13, and
- to combination meter terminal 27 for the HIGH BEAM indicator
- through lighting switch terminals 6 and 5
- through body grounds E13 and E41, and
- to terminal 2 of RH headlamp
- through daytime light control unit terminals 9 and 14
- through lighting switch terminals 9 and 8
- through body grounds E13 and E41.
With power and ground supplied, the high beam headlamps and HIGH BEAM indicator illuminate.
BATTERY SAVER CONTROL
When the ignition switch is turned from ON (or START) to OFF (or ACC) positions while headlamps are illuminated, The RAP signal is supplied to terminal 10 of the headlamp battery saver control unit from smart entrance control unit terminal 5.
After counting 45 seconds by the RAP signal from the smart entrance control unit to headlamp battery saver control unit, the ground supply to terminal 2 of headlamp LH and RH relays from headlamp battery saver control unit terminals 2 and 8 is terminated.
Then headlamps are turned off.
The headlamps are turned off when LH or RH door is opened even if 45 seconds have not passed after the ignition switch is turned from ON (or START) to OFF (or ACC) positions while headlamps are illuminated.
When the lighting switch is turned from OFF to 2ND after headlamps are turned to off by the battery saver control, ground is supply
- to headlamp battery saver control unit terminals 5 and 13 from lighting switch terminal 11, and
- to headlamp LH and RH relays terminal 2 from headlamp battery saver control unit terminals 2 and 8
- through headlamp battery saver control unit terminals 3 and 9, and
- through lighting switch terminal 12.
Then headlamps illuminate again.
AUTO LIGHT OPERATION
For auto light operation, refer to "HEADLAMP".
DAYTIME LIGHT OPERATION
With the engine running, the lighting switch in the OFF or 1ST position and parking brake released, power is supplied
- through daytime light control unit terminals 3 and 7
- to terminal 1 of RH headlamp
- through terminal 2 of RH headlamp
- to daytime light control unit terminal 9
- through daytime light control unit terminal 6
- to terminal 1 of LH headlamp.
Ground is supplied to terminal 2 of LH headlamp.
- through daytime light control unit terminals 10 and 16
- through body grounds E13 and E41.
Because the high beam headlamps are now wired in series, they operate at half illumination.
OPERATION
After starting the engine with the lighting switch in the "OFF" or "1ST" position, the headlamp high beam automatically turns on. Lighting switch operations other than the above are the same as conventional light systems.