Principles of Operation
NOTE:
- When installing a new smart junction box (SJB), it must be configured for this feature, if originally equipped. See SMART JUNCTION BOX (SJB) .
The daytime running lamps (DRL) are controlled by the SJB. The SJB operates the low beam headlamps at a reduced intensity. The DRL driver (integral to the SJB) supplies pulse-width modulated (PWM) voltage to the low beam headlamps when the following conditions are met:
- The high beam headlamps are not on.
- The ignition switch is in the RUN position.
- The parking brake is not engaged.