99 Civic Dash Lights Not Working. Once replaced all your lights should come back on that were not working. It sounds as though your stereo is interfering with your trucks dimmer reference signal.
The problem is with a set of resistors on the back of the instrument cluster. To check your fuses start by locating the interior fuse box. If the fuses are okay check the wiring harness.
First remove the instrument cluster and locate the Red wire in the Blue connector.
Last but not least you can check your light switch with a multimeter and see if it has intermittent faults. Make sure that the contacts are not corroded etc. Like a relay im guessing. Full 225 stanless exhaust with text pipe.