Heater Fan Troubleshooting

[Lean Machine]

The heater fan on my 400se is not working and I want to try and find the problem. Simple things first so I want to check the fuse and the relay. According to my hand book the fuse no.6 is shared with the mirrors and the boot lock and they are both working, so it's not he fuse. Does anyone know which relay is the heater fan? and is it shared with anything else. Next I will check the wiring and of course the worst sinareo, if its the heater fan motor do I have to remove the dash to get to it? Any help or previous experiences would be welcome. Thanks.