OFT - Left it plugged in (3wks) and now car wont start

[troek]

the blank screen/resume feature is great, and i love using it during the day for stops and what not, so much better than the old way. but its not too much work if the car is gona be sitting more than a day to just unplug it. it would be amazing if we could just plug it in and leave it forever. but we have to remember, most of us bought this just for tuning and some data logging. so these added features are an awesome bonus IMO.

[Andrew025]

When it happened to me, my car wasn't sitting not being driven though.
I drove back and forth from work which is about 10 miles each way.
I think it was maybe the 4th day when my car wouldn't crank.

[troek]

in just one night?

[Andrew025]

Originally Posted by troek

in just one night?

Over the course of 3 days.
Back and forth from work each day with OFT plugged in the whole time.

[troek]

ahh i see what your saying. yeah, best bet is like you already are doing, just unplug it over night. its a pretty mild tune, unless your tracking there's no need to monitor it every time you drive the car anyway. I only use mine if ive made changes, or if im gona be driving hard/tracking.

[Andrew025]

Yeah, it's not a big deal.
I had it mounted perfectly to leave plugged in though

[1Cor10:23]

This is why I've been trying to source an OBD extension with a built on switch. There are a few online but they're not cheap...

[Foobar]

Originally Posted by 1Cor10:23

This is why I've been trying to source an OBD extension with a built on switch. There are a few online but they're not cheap...

Would probably be cheaper to just buy an extension and splice a switch in yourself. Battery power is on Pin 16, which is the lower right most pin if you're looking directly at your OBD2 port on the vehicle (narrow side down, wide side up).

[Target70]

Originally Posted by s2d4

To flatten the battery in 3 days, it'll need to draw ~1.27A constantly every single hour. Did you measure it with a multimeter?
Not enough to crank as per troek probably makes more sense, I wonder how much it actually draws? Perhaps it's something else like keeping the ECU awake.

This ^, I was wondering the same thing. It would make sense if the ecu normally goes into a standby mode when the car is off, but when I leave it on the datalog screen it always has up-to-date info from all the sensors, so maybe it is constantly sending/receiving when the oft is plugged in.

[1Cor10:23]

Originally Posted by Foobar

Would probably be cheaper to just buy an extension and splice a switch in yourself. Battery power is on Pin 16, which is the lower right most pin if you're looking directly at your OBD2 port on the vehicle (narrow side down, wide side up).

Yup, I've got a few extensions on the way, I'll experiment later now to find a good spot to house the switch...

[stugray]

Originally Posted by Target70

This ^, I was wondering the same thing. It would make sense if the ecu normally goes into a standby mode when the car is off, but when I leave it on the datalog screen it always has up-to-date info from all the sensors, so maybe it is constantly sending/receiving when the oft is plugged in.

Perhaps the fact that the OFT is talking to the ECU keeps the ECU awake?

That would make more sense than just the OFT draining the battery.

[Foobar]

Originally Posted by 1Cor10:23

Yup, I've got a few extensions on the way, I'll experiment later now to find a good spot to house the switch...

The light dimmer panel on the left side of the driver underdash panel is a good candidate. Can remove that whole panel from the underdash panel and work on it with unlimited access. Snap it back together and route the wires along the back of the panel, good to go.

[s2d4]

Originally Posted by stugray

Perhaps the fact that the OFT is talking to the ECU keeps the ECU awake?

That would make more sense than just the OFT draining the battery.

Yes, that is what I was referring to rather than OFT flattens batteries by its own power draw.

[stugray]

If you go through the trouble of making a custom cable with a switch, just take Ignition power and route it to pin 16 of the OBD-II connector instead of Battery.
Then the OFT will only get power when the car is on.