After being in denial for several months, I’ve finally bothered to check if the devices attached to the OBDC-II port affect battery life. They do.
I have a Scangauge-e and a Garmin ecoroute HD attached by double adapter to the OBDC-II port.
The Scangauge sleeps when the car is turned off and wakes when the car wakes to pump up the brake pressure when the driver’s door is opened before being started.
The Garmin ecoroute HD is always thinking, according to the Garmin Knowledge Base.
|Question: Will the ecoRoute HD drain power from the car’s battery when not in use?|
|The ecoRoute HD accessory only draws small amounts of the car’s battery power. There should never be any instances of the accessory causing the battery in the car not to function correctly.Note that ecoRoute HD will be powered and working even when not connected to a compatible Garmin device or application.|
|Last modified on: 10/10/2011|
Well… small amounts of the car’s battery is significant when the battery is very small, as it is in the Prius. At least the article points out that power is drawn at all times.
Last weekend I was staying in Sydney and I made a point of unplugging the OBDC adapter each time I handed the car over to the valet. Even with using the car every day I didn’t want the risk of flattening the battery.
Only problem with unplugging each time is that the ecoroute HD has to reconnect to the GPS, a ritual that can only be completed when standing perfectly still.
So I’m trying with just the Scangauge attached to see what drain occurs overnight with a full battery…