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It looks like the dimmer switch, part of the MFS is your bad guy. The exact same output from the headlamp switch is used for both headlamp modes, switched from circuit to circuit by the dimmer switch, so if the hi-beams are OK... power and ground to the headlamps are also OK.
Check your violet/ white wire out of the MFS for power when switched to dims. If it's not present, investigate the MFS connector for damage to the connector pins or switch. Hi-beams come out the red/ orange wire, by the way...
No CTM is used in this year, saving you a little mental grief! It's a hard-wire situation, either the low-beam filaments in both bulbs are out or you're not getting power to the bulbs. My info shows no fused circuits after the dimmer switch, so it's just a matter of getting power from the dimmer switch to the headlamps, most likely the MFS itself.
Remember... the violet/ white wire should show power at the MFS when switched to lo-beams. If not, you're gonna need a switch.