[Blue Bowtie]

AFAIK, there is one blower, but zone ducting for the left/right sides. It may be easiest to begin at the power center (back seat?) checking for fuses and relays. Check the fan motor leads themselves for power. If there are no failed fuses and still no power at the blower motor, I'd suspect a relay or resistor array. The resistors are notorious for corroding and failing.