Battery Fail – Garmin ecoroute HD

ScanGauge II
ScanGauge II (Photo credit: bikesandwich)

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…

ScanGauge e – and a big thanks to Jon

I read a Prius forum based in the USA, I’ve joined what seems to be the only Prius club in Australia, which is based in Queensland and apart from the white GenII with the Tesla sticker I see in Belconnen, there doesn’t seem to be a hardcore Prius scene in Canberra.  I see a few Gen II, Gen III and Prius v, but none seem to have been modified or tinkered with in any way.

So it has taken me from Australia Day until the end of September to finally meet someone who knows his LOD from his LHK.

Jon was visiting Canberra for Floriade (you really must see it) and took some time away from his family to meet me, talk Prius and sell me a ScanGauge-e.  Here’s the thing… the reason he had one for sale is that he had already reached the limit of 4 ScanGauges daisy-chained together and couldn’t fit any more.

Jon has not 1, but 4 ScanGauges and a tyre pressure monitor in his Gen II. Every conceivable piece of data captured.

As mentioned, I already use a Garmin 2460LT GPS and Garmin Mechanic with ecoRoute™ HD.  The ecoroute captures data from the OBDCII port and transmits them by Bluetooth to the GPS for display.  It is even clever enough to store capture data until the GPS is connected.

In my short time of using the ScanGauge-e I can say that there’s a fair degree of overlap with the functions in the ecoroute.  However, there’s a difference in how data are presented: The Garmin has separate screens for Fuel Consumption, ‘eco score’, 5 gauges (out of a choice of 12) and of course the map.  ScanGauge-e has a 2 line dot matrix display that can display two parameters from a choice of 19 and a fuel consumption graph.  Both have a method of recording fuel used, but whereas the ecoroute records each fill up on a spreadsheet, the ScanGauge uses the data to calibrate and calculate Distance to Empty and similar functions.  Since the DTE function on the Prius is incredibly conservative (I drove 35 km beyond the DTE = 0km mark at freeway speeds and still had 4 litres of fuel left) having an independent DTE is a boon, especially if I want to hit my first 1000 km tank in relative safety.

Jon helped with the initial set-up and calibration.  I even had to fill up, which is the time to start the calibration.  Only problem was the fuel price set at $75.0.  Despite holding the button in, the value took a long time to change.  Of course, the hidden cents value was dropping rapidly, but only the tens of cents value was displayed.  Today I used a handy clamp to wind the price back to a more realistic cost per litre.  Only took 20 minutes to reach $1.46.

My clamp-based, button-holding, value-reducing solution.  Halfway there

Makeshift installation was a bit wiry.  The OBDCII splitter worked fine (you can’t always feed OBDC data to two devices). The main issue was the amount of cable to conceal and devices to place.  Today I re-installed all of my devices in the interests of safety and efficiency.  I routed the cables under the steering column, using some unused switch blanks to enter and exit the dash.

Neat. In a fashion