It was after few rides I noticed that the brake lights were not functioning. I checked it with pressing the pedal and recording the car from behind while doing it and had no luck. But all of the other taillights worked except for the reverse light and brakes. So I started diagnosing from the top.
I pulled the knob to get parking on and wired the brake lights from outside. The brake lights had earth coming from the harness so the holders were not directly contacted to the car body. The lights responded to the +12v I got from the parking pin and that confirmed that the bulbs were okay and the continuity from the tail light box to the wire harness socket was okay.
Then I looked above the brake pedal and found the switch that sends the signal to the lights. It had 2 contacts with one +12v wire clipped to it which sparked as it came in contact with the body mistakenly and yes no need to mount test lamps after that. The other contact is supposed to deliver +12v when the brake pedal is pushed. I mounted the +12v to one side (Upper clip) and mounted the test lamp to the other contact (lower clip). I did it with no prior knowledge to what goes where but with the simple belief that it had to be a simple mechanism to connect the two wires when brakes applied which allows the connections to be reversible. After mounting the free end of the test lamp to the body I pushed the brake pedal and luckily the test lamp was lit. Therefore there was no error in the brake switch.
After the two observations it was obvious that there has to be a continuity problem in the wire harness that runs behind to the tail lamps. So I removed the plastic panels of the right side of the car floor, removed back seats and lifted the velvet clothing to uncover the wiring harness. The wiring harness had been dangerously damaged and it had been rubbed over the car body by the seat and the brake light wire had been broken from the front part of the harness. The wire that goes to the fuel gauge in the dashboard had been completely worn about 7 centimeters off due to the continuous rubbing. The main issue here is that the wire harness lacking proper casing to cover it self properly under the seats and inside the panels.
So I removed the damaged wire parts and replaced them with fresh automobile cables (32/0.20 mm) and soldered them. After treating the damaged wires I covered the harness with insulation tape to prevent damage to a certain extent.
Meanwhile I earthed the fuel Gauge line to see if the fuel gauge works, Luckily it raised halfway up and that was a good sign.
After covering up and soldering the wiring harness was carefully placed to prevent further damage and we have working brake lights.
Pahan's Garage 