The service manuel is very helpful, we where able to restore the device to its working operation again.
Text excerpt from page 6 (click to view)
KRC-16,191,265L/R,26,291
TEST MODE
1. How to enter the test mode • Reset the unit while holding the "FM" key and preset "6" key. • All indication segments go ON at the beginning of the test mode. 2. How to release the test mode • Simply reset the unit. • (NOTE) The test mode is not canceled by ACC OFF, power OFF, momentary power down or the panel off. 3. Audio adjustment • Set the volume level to -10dB (which is shown as "30" on the display). • Loudness OFF. • The BASS/TREBLE and BALANCE/FADER can be set to the full-boost/full-cut and fullfront/full-rear each by pressing the "Track UP" / "Track DOWN" keys. • Sound coordination doesn't appear for the feed.
