Model 58L1350U – C suffix for Canadian model.
Got this TV in with report of no backlight. I tried probing the LED connector from the back but couldn’t figure out the wiring. Taking off the panel, all the backlights tested good so I put the panel back. The TV appeared dead and did not power on. A post on badcaps indicated to check Q301 for shorts. Q301 was shorted drain to source and measured about 400 ohm both gate to drain and gate to source. Part number was FQPF16N25C (N-CH, 250V, 16A, TO-220F). The main fuse was not blown. I replaced this part and the TV powered up. The standby light was not on but this may be set in the menu. I checked the backlight level after doing a reset and the default for standard mode is 5 out of max 50.