Today I got in my mom's 2010 Buick lacrosse and turned on the heated seat because it was below 30, and it turned on but didn't heat up and after a minute the lights would turn off. I tried on all 3 stages and the same thing happened. I turned the cooling seat on to see if it was like that but it worked just fine.
After checking the obvious such as fuses and relays check for power going into the seat heater wiring under the seat. If there is power and no heat then either you have a broken wire inside the seat or possibly a bad thermostat inside the seat. (It's very common on an old car with heated seats for heating grid wires to break, especially in the seat bottom.)
Fuses? Connection?
How did you know the cooling seat worked when you said it was under 30 degrees?
