Seat Heater Relay
Remove seat heater relay from underhood fuse/relay box. With power disconnected, check for continuity between terminals No. 1 and 2. See Fig 1 . Continuity should not exist. Using jumper wires, connect terminal No. 3 to battery voltage and terminal No. 4 to ground. If continuity does not exist between terminals No. 1 and 2, replace relay.