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

So for the past 3 weeks, I've left the OFT plugged into the car. Prior to this, I used to unplug it whenever I would park my car but after reading up about the new power saving mode in the recent update, I decided to just leave it plugged in. OFT is updated to the latest firmware.

Every week for the past 3 weeks, I used the car for 5 days and it was parked for 2 days with OFT plugged in. As of today, the car has been parked for 2 days and I go to start it, no go. Thankfully its parked inside my garage and I'm not left stranded somewhere. Last week I started the car after being parked for two days without any issues. No lights or electronics were left on this time when I parked the car two days ago. So my only guess is that it must be the OFT

The reason for my post is to figure out if anyone else has had this experience? If so, to warn others not to leave the OFT plugged in when parking for a few days.

I apologize if this has been mentioned before but I didn't come across anything like this before

I face-palmed after the first sentence, and started to conjure up ways to flame you... but after the remainder of the post, it donned on me you're a good guy and that I am a jackass.

gl OP, hope it works out! May this be a good lesson to the folks.

P.S. Would be awesome to have OFT integrated into the HU

The OFT can't possibly keep you from starting your car any more than keeping a code clearing tool plugged in. My guess is that something else drained your battery given the OFTs very minor current draw in sleep mode. Looks like you just need a jump start to get it up and running.

Yep, also I left mine plugged in for 3 days and it flattened by battery. Had to cancel my plans and trickle charge it overnight. Now I always unplug it if I know I won't drive it within 24 hours.

I believe in 'low power mode' the backlighting on the screen is still active and using some power.

I also unplug mine when it's gonna be more than a couple days of not driving. I wonder if it's possible for the OFT to be completely off yet still plugged in.

If it can't be done with software I wonder if it could be as simple as adding a toggle switch to the cable that cuts the power wire without having to unplug it every time. It would start back at the start screen instead of keeping its place like it does in low power mode though.

What's the actual current draw?
Pretty easy to do a calc on how many days it would take to drain the battery.

It's 3.

3A or 3mA?

3 days

Same thing happened to me.
Just had to jump my car and it was good.
I no longer keep it plugged in though.

this is all given that you have a full battery. it takes quite a few miles to recharge a battery, and if your constantly driving a couple miles, shuting down and restarting, your battery will always be teetering on the edge of "too weak to crank". wont take too much current draw to push you over that edge.

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.

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.

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.

in just one night?

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

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.

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

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).

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.

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

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.

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.

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

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.

I don't think you want to do that, since the OFT wants to know when the ignition is off during a flash cycle. You'd dump the whole flash process.

Yep, other OBD2 devices also need to be plugged in while you perform an off/on sequence. Suppose you could put in a triple switch or something, off, ignition, and battery, then you can choose which mode you want, but that's starting to get carried away. Maybe just Battery/Ignition to keep it simple.

this ^^^

I was planning on adding a switch to the extension for leaving it on all the time but just unplugging the extension and using the original OFT cable for flashing just to prevent any issues.

I flash with 1 meter extension in with oft and with tactrix that writes 7 times speed of oft no issues

I meant preventing any possible connection issues that would arise from having the switch soldered in.

Noob OFT question...does the OFT NEED to be plugged in all the time? More specifically, if i were to buy a OFT, connect it and flash it...does it need to stay connected/plugged in?

Soo noob, I know...

Nope. It only needs to be plugged in when flashing the ECU, datalogging or when using the realtime data displays/alerts.

Cheers,
shiv

I keep my car garaged as well. After the recent update I no longer leave it plugged in due to thinking it was causing battery drain. I noticed that it seems to not exit the real time data display mode automatically anymore. I thought it was great at first until I went to start my car after it sat for about 24-36hours. May or may not have been the OFT, but either way I no longer leave it plugged in. No battery problems since then and car has been parked for 3+ days.

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

Same thing happened to me. I Unplug it at night and it no longer happens. I freaked out when it first happened.

lollllllllllllllllllll

UPDATE:
This week, I've had it unplugged and never had any issues with starting the car after parking for a few days.

Well, I am glad to know, I wasn't the only one with this issue. Simply because its reassuring that it couldn't have been anything other than OFT. Last week when my car wouldn't start, I am sure nothing else could have been consuming power other than the OFT. Anyway, just for precaution, I keep jumper cables in my car now.