I agree with gts mate it's not worth the fuss,but if you really want a play then we can point you in the right direction.
The key components that should be checked are located under the keypad,so remove the three phillips screws that are located around the keypad chassis and gently lift out the keypad and remove the ribbon cable.
At the top are two voltage regulators,(the chassis you have removed is screwed through these and acts a heat sink),replace both regulators.
Below you will see a bank of diodes (D1's) check these for continuity,one or two will have failed.sandwiched between the two banks of D1 diodes you will see a resistor,replace that for the same value.
They are the key components that fail and cause the split DC/AUX voltage faults on the Accenta/Optima pcb,s.
Think we have all seen the fried resistor under the keypad's on these many times lol.
I still don't think it's worth the hassle though :D
e manno
November 2013