driver's heated seat stopped working

[mikesands]

Passenger seat still works so presumably not just a fuse unless they have separate fuses.  Read somewhere about wires under seat becoming disconnected so will check that.

But also read that there are two separate relays and a good test would be to swap them over - can anyone tell me where these are (which fuse box and relay numbers)?

Thanks

Mike

[mikesands]

All plugs and wires under the driver's seat look sound, and the single 20a fuse is intact (but that was bound to be as there's just one for both seats).  Can't find the relays though.

Mike

[mikesands]

I'd like to try swapping the seat heater relays between the two seats, but is it likely I can do this without removing the seats from the car?  I can see two or 3 connectors that come apart, but none of them look like a relay.  Also it's not obvious how to separate any of the connectors (I think there should be 3 year college courses in how to fathom auto electrical harness connectors 😀).

Mike

[ColinBarber]

There are no relays involved. 

Does the light come on the control switch? If yes, are both the seat base and seat back heater not working?

 

 

[mikesands]

The light comes on on the control switch.  Neither the seat base nor seat back heaters work on the driver's seat but both work on the passenger seat.  Not sure whether this is relevant but the interior lights were left on and ran the Battery completely flat.  The seat memories had disappeared but my daughter thinks the seat heating was off before the Battery went flat (I am suspicious about coincidences though).  I restarted the car by connecting a moderately discharged spare car Battery in parallel with the flat one while it was in the car.  All seems good now with the Battery, but could something have gone wrong with the seat heater as a result of the flattening or recharging of the Battery?

I've looked at that diagram a few times Colin, but it looks too simplistic compared to what's actually under the seat.  One would imagine that it would be easy to simply unplug both 'seat heater controls' and swap them over, but I can't identify them in real life.

Mike

Edited December 5, 2023 by mikesands

[ColinBarber]

The diagram is simplified to just the heating components - obviously its more complicated than that in real life with the wiring for the motors, sensors and airbag.

I'd certainly start by trying to swap over the control module - it is the same part on both seats.

[mikesands]

.... But that's my problem I can';t identify what the control module actually looks like

Mike

[ColinBarber]

12 minutes ago, mikesands said:

.... But that's my problem I can';t identify what the control module actually looks like

Mike

looks like this:

https://afyal.com/en/part_8750105010_Toyota