I recently fitted a K1S Dashcam (Koonlung K1S) to an Abarth 500, and wanted to have a tidy install with no wires showing if possible. To avoid having it plugged into the 12V lighter socket, I needed to find a suitable place to wire it into the dashboard fuse box. Although the fuse box is described in the manual, it doesn’t indicate which fuses are permanently live, and which are switched live. This information is not readily available on the interwebs either, so I figured it out with a meter and made some partial notes in the table below.
|F12||7.5||Right dipped headlamp power supply|
|F13||7.5||Left dipped headlight and headlight alignment control unit power supply|
|F32||7.5||Constant||Front, rear and luggage compartment roof lights|
|F36||10||Diagnosis socket, radio, climate control, EOBD|
|F37||5||Brake light switch, instrument panel node|
|F38||20||Door central locking|
|F43||15||Windscreen/rear window washer pump|
|F47||20||Constant||Driver's side electric windows|
|F48||20||Constant||Passenger side electric window|
|F49||5||Switched||Parking sensor, control backlighting, electric mirrors|
|F51||7.5||Switched||Radio switch, Blue&Me, climate control, brake lights, clutch|
|F53||5||Instrument panel node|
Obviously, there are a lot of fuses there which are “safety critical” such as the Airbag, Brake Lights etc. which are best avoided. Also, the fuse layout is probably the same on the standard Fiat 500, but you know… they might not be, so use this information at your own risk!
The picture of the fuse box in the manual is upside down (for right hand drive models) so here’s a rotated version with the fuse ratings added in blue. The Switched (S) and Constant (C) supply fuses are (partially) labelled in red:
To avoid cutting any wiring, I used one of these mini “add-a-circuit” widgets, which allow you make another connection to an existing fuse:
They need to be used with some care, because you could fit the original and new fuses in the wrong places, and fit it in the wrong orientation. As there were no instructions with it, I used the resistance range on my meter to double-check the wiring before fitting the fuses.
In the picture above/below, the left blade is the input side, which needs to go to the live supply in the fuse box. The right hand pin nearest the wire is the output, after the fuse. The original fuse goes in the lower two holes. The new fuse for your added circuit goes in the top two holes, and the output of that fuse is the red wire. Pretty self explanatory really:
When installed in one orientation (12V input to left blade as described above), the input goes through F1 to item A and the input goes through F2 to item B. If either fuse blows, the other item should still have power. However, when installed in the reverse orientation, note that the input will go through F1 to item A but will go through both F1 and F2 in series to item B. So you need to consider the orientation when installing it.
The wire projecting from the side of the “add-a-circuit”, and the fuses projecting sideways can make it impossible to fit in some positions and orientations (e.g. if they interfere with the side of the fuse box). This can limit your choices on which fuses it can be connected to.
Here’s a shot of it fitted in situ on the fuse box. In this case, it’s inserted into F49 (Parking Sensor, control backlighting, electric mirrors). Using a meter, I found that the left terminal in F49 was live with the fuse removed, hence the output wire faces right when installed:
Caution: whereas the left terminal of F49 was live, I found that it was the right terminal of F47 and F48 that was live, so it isn’t the same for every fuse.
For the ground connection, I used an eyelet crimp terminal under one of the two bolts which secures the bonnet release handle to the chassis. This is a very short distance from the fuse box, so easy to run a wire.