Fuse 12 Investigation...

When I bought my car, it seemed that some equipment did not work. The clock, the antenna, the courtesy lights, door entry-lights, trunk light, hazard-lights, vanity mirror lights...

Honestly, I did not recognise all these elements not to work immediately, but only later after finding that the hazard lights are connected to fuse 12, while the turn signals (via fuse 5) worked fine...

Blown Fuse...

So, then I checked the fuse box on the right footwell area, and what a surprise! Fuse 12 was blown. So, that was an easy one, I just had to replace the fuse. Done, Boom, fuse blown again... An old-fashioned shortcircuit... :-(

So, maybe just to replace the hazard light switch... So I opened up the middle console to reach to the switch and I disconnected it. Replaced the fuse again and Boom! Fuse blown again :-(

Really time for a more thorough investigation...

I was at that time concerned about the hazard lights for the technical check-up, but they made no fuzz about it. Pfffhh...

So, with the car being technically approved, I started to drive the car last summer and promised myself to investigate the issue further during the winter break, as I should have plenty of time by that time...

Winter passed by...

Nothing happened to the car in the winter, although I made that promise to myself... So only in late February (22 and 23) I started to give it a good look.

So many devices...

So, starting to investigate Fuse 12: what devices are behind fuse 12?

So fuse 12 is important for quite a few devices, so indeed a good reason to do a structural fault detection.

Although..., I have seen on several internet pages that the retractable antenna is very often a cause of issues. So, trying to be smart, I disconnected the antenna, replaced the fuse, Boom!, again fuse blown :-(

Ok, ok, I gave up, let us start the real structural fault detection...

However, according to the fuse table, also the radio was supposed to be behind fuse 12, but that one has remained in service... So somebody has hampered with the wires. An additional topic to investigate...

Disconnecting all devices

So, there I started, disconnecting the devices 1 by 1: the trunk light, the entry lights, the roof lights, the vanity lights (in the mirror in the sun shields), the warning monitoring system (behind the glove compartment; but hey!, that one was already disconnected).

Aw, to reach the clock I had to remove the instrument panel. For this I needed special tools, I did not possess.

Ok, maybe I can disconnect the wires at the fusebox. This gives me also the possibility to investigate any short circuits by the wiring touching the car frame...

However, that was also easier said than done. I did not see an easy way to disconnect the wires from the fuse box while maintaining the possibility to reconnect them again later on...

So, there I was: halfway disconnecting devices, but not able to go all the way without severe implications... So, let us take another white torpedo fuse, connect it and... nothing... The fuse did not blow... Yippie! No need to remove the clock or to disconnect the wires from the fusebox!

I kept a few white torpedo fuses aside, so I could start reassembling everything to see which device would cause the short-circuit.

Fuse 12 survived

So, one by one I reconnected the several lights and put them back in the cases, sometimes I needed to glue, e.g. the vanity mirror back into the sun shield, the antenna, the hazard lights. But nothing happened... I even reconnected the alarm unit. Now something happened: the horn in my car started to protest loudly, so I quickly disconnected the plug again and kept the device as it was: disconnected.

So, I reassembled everything, but fuse 12 did not blow, not even once?! So I was not able to find the culprit. Although I have a suspicion: one of the roof light connectord was not very sound, so I isolated it a bit better before placing it back in the windshield. Other than that, no real changes...

I think the first test drive needs to show if fuse 12 will really hold.