Volvo 240 Seat Heaters

The seat heaters in a late 240 are controlled by a switch in the parking brake console and a thermostat. There is a panel under the seat back and one under the seat bottom upholstery. They are wired in series, connecting to a harness under the seat frame. The usual problem I have repaired is an open circuit caused by the nichrome wire breaking at the thermostat terminal.