Best way to wire a dashcam with parking mode in Mercedes W211 E320
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W211, X254, W177
Best way to wire a dashcam with parking mode in Mercedes W211 E320
Hello,
I need to supply power to a dashcam in my W211 (2005, European version, E320 4MATIC, 3.0L V6 Diesel).
The dashcam has a parking mode, which requires 3 wires:
I initially considered the "instrument panel fuse box" (the one next to the driver’s legs, accessible when the door is open), but it looks like none of the fuses 21-42 is suitable.
Now I am thinking about the "engine compartment fuse box", using both F54a and F54b — the cigar lighter fuses (15A, ATO/ATC). Position F54a would serve as ACC, and F54b as the constantly present +12V.
(By the way, that’s a quite interesting Mercedes solution — you can change how the cigar lighter is powered by simply choosing which 2 out of 3 pins the fuse is attached to.)
The only challenge is getting the wires through the firewall (the metal plate between the engine and passenger compartments), but there is supposed to be a passage (grommet) near the engine compartment fuse box, right?
Is this a good idea? Any other suggestions?
PS: No worries about discharging the main battery — the dashcam will be configured to turn off completely if the main battery voltage drops below a selected threshold, which can be set between 11.8V and 12.6V in steps of 0.1V.
I need to supply power to a dashcam in my W211 (2005, European version, E320 4MATIC, 3.0L V6 Diesel).
The dashcam has a parking mode, which requires 3 wires:
- +12V (constantly present)
- ACC (+12V present when ignition is on)
- GND
I initially considered the "instrument panel fuse box" (the one next to the driver’s legs, accessible when the door is open), but it looks like none of the fuses 21-42 is suitable.
Now I am thinking about the "engine compartment fuse box", using both F54a and F54b — the cigar lighter fuses (15A, ATO/ATC). Position F54a would serve as ACC, and F54b as the constantly present +12V.
(By the way, that’s a quite interesting Mercedes solution — you can change how the cigar lighter is powered by simply choosing which 2 out of 3 pins the fuse is attached to.)
The only challenge is getting the wires through the firewall (the metal plate between the engine and passenger compartments), but there is supposed to be a passage (grommet) near the engine compartment fuse box, right?
Is this a good idea? Any other suggestions?
PS: No worries about discharging the main battery — the dashcam will be configured to turn off completely if the main battery voltage drops below a selected threshold, which can be set between 11.8V and 12.6V in steps of 0.1V.
