New car - fuse box power "vanishes" once the car is started

[oohaj]

Hi there! I'm in a bit of a pickle. I'm moving my dashcam from an older Honda Odyssey to the current generation and I ran into some problems.

- the fuse box has 12V when the car is off. As soon as I start the car (or turn on the ACC power) the 12V goes to something like 0.02V. The only fuses that stay at 12V are for the door locks.
- If I tap the door locks for battery power I still need ACC power and that I can't find at all. At least not on any of the cabin fuse boxes.

Is this some kind of smar power saving technology - the computer kills power to the circuits that aren't used? How can I bypass that?

I'd appreciate any suggestions. I've hardwired a few cars in the past, including '20 Acura, but none had this issue and I'm stumped. I'd prefer not to disassemble half of the dashboard to tap directly into an ACC powered wire, as this is a leased car.

Thanks!

 

[jokiin]

welcome to CAN-BUS, pain in the ass to deal with at times

 

[Mtrev]

Hi there! I'm in a bit of a pickle. I'm moving my dashcam from an older Honda Odyssey to the current generation and I ran into some problems.

- the fuse box has 12V when the car is off. As soon as I start the car (or turn on the ACC power) the 12V goes to something like 0.02V. The only fuses that stay at 12V are for the door locks.
- If I tap the door locks for battery power I still need ACC power and that I can't find at all. At least not on any of the cabin fuse boxes.

Is this some kind of smar power saving technology - the computer kills power to the circuits that aren't used? How can I bypass that?

I'd appreciate any suggestions. I've hardwired a few cars in the past, including '20 Acura, but none had this issue and I'm stumped. I'd prefer not to disassemble half of the dashboard to tap directly into an ACC powered wire, as this is a leased car.

Thanks!

I've never worked with Hondas but that sounds very strange, are you definitely testing it correctly? what does the fuse info say the fuses are used for?

 

[oohaj]

I've never worked with Hondas but that sounds very strange, are you definitely testing it correctly? what does the fuse info say the fuses are used for?

I pretty much tested every fuse. Things are perfectly normal when the car is off - 12V in the usual spots, power doors, power seats, mirrors etc, and no power on any accessory circuits - lighter, wipers, etc. Stuff gets annoying when I turn the car on. Most of the circuits appear to turn off and I can't find anything that would be ACC power.

 

[Kremmen]

I don't know about your model but all UK Hondas have what is called an 'Option Connector' it is an empty fusebox slot that can contain anything from 4 to 6 unused pins.

Those pins are usually:

Permanent power
Reverse selected
Lights on
Ignition Position 1
Ignition Position 2

If you can find it with a multimeter then that's where to aim for.

Here's a thread on a UK Honda forum where they sell the option connector plugs but any insulated 2mm crimp connector will work just fine.

8,9,10 Gen Civic, 3,4,5 Gen CR-V, 3G Jazz, Honda E...

www.civinfo.com

 

[oohaj]

Thanks for the info! I'll check it out!