Well about the combination switch, actually the fault occurs because there is no relay in the headlight circuit apart from a common relay for both high and low beams thats located in engine compartment relay box.
The switch fails to work because the LOW BEAM PIN heats up as well as oxidizes/corrodes at the connector on the combination switch. Also, partial erosion occurs inside the switch which can be corrected with sand paper and slightly adjusting gap of contact points (or you can say, slightly bending copper plate that supports one end of low beam contact, to keep pressure on the contact when its made).
Hard to make sense without pictures but one can see what I am talking when switch is disassembled. I shall do the other combo switch(from RL) that went fault last year and try to take pictures. The key is to disassemble the part. After years of use, and that too under heat when headlight is on, the plastic is brittle and its easy to crack the locks. Once disassembled, its fairly easy refurbish job. Dont forget to scrap pins inside connector as well to remove oxidation.
Next is to install two relays with the switch so that in future it does not heat up and remaining life in it is prolonged. One for low beam circuit and one for high. I'll try to highlight the connections from the manual.
1- You may take 12V from fusebox nearby
2- The relays are infact bypassing the high current away from the switch. The OEM wires themselves are capable. Thats why connection to GROUND is not taken from CHASSIS and black wire is Stripped and used as it is.
ABout the power side mirror switch, its easy to disassemble. In my case, the PCB track was scraped due to movement of the sliders. There are about 4 sliders inside. 3 for direction and one for LEFT or RIGHT motor selection.
I just repaired fine track connections and voila. It worked like a charm. Dont forget to use small amount of solder or your switch wont assemble :-).
Price of Combo Switch New From Honda: PKR 4000+. I guess we bought around 4700 for the RL. This time i wanted to save some cost
Price of Power Mirror Switch: Dont know. Was eager to DIY this and it worked.