There is no relay for low beams , the ( SJB) smart junction box , a control module an fuse / relay center in one.
When the SJB receives an input requesting the headlamps on, the SJB supplies voltage to the low beam and high beam bulbs as necessary.
The smart junction box (SJB) monitors the headlamp switch position by sending voltage reference signals on multiple circuits to the headlamp switch. At any given time, one of the signal circuits is routed to ground. If the SJB does not detect any of the inputs to the headlamp switch is active (routed to ground) for 5 seconds, the SJB turns on the exterior lights and keeps them on for 10 minutes after the ignition switch is turned off (or 10 minutes from the time the SJB does not detect any headlamp switch input if the ignition switch was already off). If the SJB detects multiple circuits short to ground, the SJB implements a planned strategy depending on the multiple inputs received. If either of these situations occur, the SJB should NOT
be ruled immediately as being at fault. This is normal behavior of the SJB design as it has detected a fault with the inputs from the headlamp switch.
Visual Inspection Chart
- Headlamp switch
- Multifunction switch
- Headlamp assembly
- Battery junction box (BJB) fuse(s):
- 19 (40A) (low beams)
- 26 (15A) (LH high intensity discharge [HID] headlamp)
- 27 (15A) (RH HID headlamp)
- Smart junction box (SJB) fuse 11 (15A) (high beams)