Cold bottom on way to work

Hey good folks of the forum, anyone help with a little heated seat problem?

I have factory heated seats in my 2001 ES, the passenger one works with someone sitting in it, but the drivers one never works.

Pressing the switch makes the relay under the seat click, but no heat!

Anyone know of common issue with these seats, and if parts are easily available?

Cheers in advance. I'm off to defrost the behind!

Took this from the RAVE manual

HEATED SEATS
DESCRIPTION
General
The heated front seats are switched on and off by pressing either of the switches mounted on the centre console. The heated front seats are operated independently of each other. The switches also incorporate an illumination LED to show when the seat heaters are switched on.
OPERATION
General
Feed from the positive battery terminal (C0192) is supplied to fusible link 3 and fusible link 4 of the engine compartment fuse box (C0632) on an R wire. Fusible link 4 (C0574) is connected to the sunroof relay (C0587) by an NW wire. The earth path for the relay coil is controlled by the Central Control Unit (CCU) (C0592),
Fusible link 3 (C0571) is connected to the ignition switch (C0028) by an N wire. When the ignition switch is turned to the 'ignition' position, current flows across the switch (C0028) to fuse 8 of the passenger compartment fuse box (C0588) on an OG wire.
When the CCU receives an ignition feed, it energises the sunroof relay by providing an earth path for the relay coil. The energised main relay provides a feed to fuse 29, which is also located in the passenger compartment fuse box.
Fuse 29 (C0584) provides a feed to the LH heated seat switch (C0249) and the RH heated seat switch (C0250) on N wires.
LH Seat
When the LH heated seat switch is pressed, current flows across the switch contacts (C0249) to the LH heated seat relay (C1221) on a US then R wire. Operation of the heated seat relay (C1221) is controlled by the temperature sensor on a G wire. The temperature sensor is a normally closed switch. Current flows across the switch to earth on a G then N then B wire.
When the temperature of the seat is within acceptable levels, the heated seat relay (C1221) provides a feed to the seat heater elements on an RW wire. The elements are wired in series and earthed on an N then B wire.
If the temperature sensor detects the temperature of the seat is too high, cuts the earth path for the heated seat relay. This de-energises the relay until seat heat temperature falls back within acceptable levels.
RH Seat
When the RH heated seat switch is pressed, current flows across the switch contacts (C0250) to the RH heated seat relay (C1221) on a UK then R wire. Operation of the heated seat relay (C1221) is controlled by the temperature sensor on a G wire. The temperature sensor is a normally closed switch. Current flows across the switch to earth on a G then N then B wire.
When the temperature of the seat is within acceptable levels, the heated seat relay (C1221) provides a feed to the seat heater elements on an RW wire. The elements are wired in series and earthed on an N then B wire.
If the temperature sensor detects the temperature of the seat is too high, cuts the earth path for the heated seat relay. This de-energises the relay until seat heat temperature falls back within acceptable levels.

TEMP SENDER??
hope this helps

that was reet good Bigeee

You should be able to test for continuity through the heating elements.

Remember reading somewhere not to allow anyone to kneel or stand on heated seats cos of likelihood of damaging the elements...