QUOTE(delsoo @ Jan 21 2015, 07:54 PM)
Ok. I went to shop just now. They said switch rosak. They replace a switch, everything work as normal again
When the lights are not working, the fault can come from many things: fuse, switch, bulbs, wiring etc. In your case the fault was the switch (at the gearbox), not the fuse, or bulb, or wiring.
For DIY troubleshooting, if the reverse light & sensor are not working, the switch is the 2nd thing to check, after confirming the fuse first. Because in terms of dismantling/checking it is easy to check the fuse. The switch checking needs a multimeter to confirm either continuity, or the supply at the socket, all these are best left to the workshop.
So if you want to DIY, the most you can do is check the fuse first, if fuse is ok, go to the workshop for them to use suitable equipment to check the others. They have the equipment to check the wiring supply & the switch.
(From your earlier info, the reverse sensor stop working after the accident, so we try to link this event... the switch in front will not be damaged by the impact at the rear. This shows it is difficult to trouble shoot using info like this without actually working on the car...)
This post has been edited by Albert B: Jan 21 2015, 08:21 PM