Steering Wheel Volume Control

[Simons]

My new to me LS430 has what I believe is a not that uncommon problem with the steering wheel volume controls. They only seem to bring up a preset volume. They wont actually adjust the volume up or down. I have read that I might need to spray some contact cleaner into the switch or that there may be some sort of reset to be done. Any advice or pointers please? Normal dial on the audio system works fine.

thanks

Simon

2003 LS430 45k