instrument panel not working - voltage levels?

[reynolr]

Instument panel illumination has not worked since buying this car (1996 Civic DX)
I check the dimmer switch:
Red and Red/Black wire both have approx 8 volts on them. My schematics don't indicated voltage levels but I'm thinking that is wrong.
The previous "owners" i.e. neglectors, put in some trashy after market radio in place (because at least if the car don't run the we can always listen to the radio).
I took that getto box out but still have this problem: no illumination lights on dash but all other lights (check engine (of course) and blinkers, high beams, etc) work.
I've seen posts that suggest the computer is faulty. Any thoughts?

 

[RonJ]

In the unplugged dimmer switch connector with the light switch on, what voltage to body ground do you measure for the Red/Blk wire?

What voltage do you measure for the Red/Blk wire if you use the Blk wire as ground?

Do the lights turn on if you jump the Red wire to the Blk wire in the connector?