Alright guys, I'm really hoping someone can help me with this because I really don't want to have to bring the car into the dealership if I don't need to.. I'm past the warranty point, so I'd rather not have to pay a bunch of money for something that may be an easy fix.

This all started a week ago when I took a nap during lunch in my car.. I normally have the radio playing, but I'll keep the car in ACC mode so that the battery doesn't die on me. But in the midst of my nap, it was getting pretty warm in the car, so I wanted to crack the window a bit. And as you all know, there isn't power to the windows in ACC mode, so pushed the start button to turn the car on without starting the engine. I forgot to put the car back in ACC mode, and the battery died on me. I had a coworker jump my car with jumper cables, and I figured everything was fine.

I've done this multiple times, and I'm certain that I didn't reverse the polarities or anything while doing the jump, but when I got into my car to drive, I realized the NAV screen wasn't powered on. It was only the NAV screen that didn't work, all my climate control buttons and radio worked fine. A friend of mine told me that it probably just a blown fuse and to check the fuse boxes under the hood. I didn't have time to do that until today, mostly because it's been raining and I could deal with an unpowered NAV screen.

Even with the fuse diagrams on the lid of the fuse boxes, I didn't know which fuse was for the NAV screen (I read somewhere that there might not be a fuse that's designated only to it) so I decided to just check every fuse for both fuseboxes under the hood to see if any of them were blown. I didn't pull out any of the relays, just the fuses, but I didn't see anything wrong. I know there are more fuses under the dash but I didn't touch any of those. After checking each fuse and reseating them.. some new issues came up.

Not only did the NAV screen still stay unpowered when I started the car, I noticed the Slip Indicator light is always on when I start the engine, and the dash stays unpowered in ACC mode. Also, the car does not respond to any of my keyfob buttons. I have to manually pull out the key from the smartfob and stick it in the doorhandle to lock it now.

Anyone have any suggestions? I'm at a complete loss on what I could have done to cause this second batch of issues.. I figured that everything I did was reversible.. I'm pretty sure (not 100%) that I put all the fuses back in the correct positions where they were pulled.. but I could be wrong. If someone could take a picture of their two fuseboxes under the hood in their default positions that would be much appreciated... but I'm still not certain that that would correct these issues.

I guess at this point, the best option is to take it to the dealer and have them sort it out.. but I'm also not sure how much something like this would cost.. if it's really just a simple fuse issue and no hardware needs to be replaced, how much do you guys think they'd charge? I'd be pretty upset if I had to pay more than $150 if there was nothing that's physically broken/damaged.

Anyway, I'm open to suggestions before I take it to the dealer.. has anyone encountered something like this?

Let me know what you guys think, thanks. Sorry for the long write up.. I tend to get really wordy when I write..

Oh yeah, it's an IS 350 2015 F-Sport

 

Yeah, it's the original battery, but I haven't had issues with it in the past... all of the previous times that I needed to jump it, it was my own fault (i.e. leaving it on while i nap, or forgetting to turn off the emergency lights).. jeez, i'm coming off pretty airheaded in this post hahah. but yeah, the battery should be okay but do you think that would cause or fix all these other issues? I feel like even if I replaced the battery, the issues would still be there.

 

i too think it's the battery. If your battery has died multiple times due to draining, your battery has gone through a lot and is the likely cause for your issues.

Also, keeping the car in ACC mode does not save your battery. Your battery is the only thing powering your electronics, so if anything is ON, then it's running off of your battery. You're draining it every time you use any electronics without the engine running. The battery needs the alternator to be running in order to keep it charged up.

 

hmm okay, now that i think about it, it does make sense.. hopefully this fixes it. I'll go get the battery changed this weekend and let yall know. that'd definitely be a much cheaper fix than the dealership.. plus, it'd be nice to know that i didn't screw anything up!

fingers crossed!

Thanks guys!

 

You want an even cheaper fix...get your battery from Costco. Their “Kirkland” are relabeled interstate batteries. One of the best brands IMO.

 

Did you check the fuse box under the dash? There's 3 fuses there that pertain to the radio/NAV system. Radio, amp 1 and amp 2.

 

Thanks guys! Am going to go to Costco tomorrow morning and hope that a new battery solves the everything.. just found out the garage door button on my rear view mirror doesn't work either.. sheesh, problems all over the place.. I really hope it's the battery. Good to know about the return policy as well.

I'll keep yall posted!

 

if the engine starts without issue then its not the battery for those faults.
The battery still probably eventually needs to be replaced if this is still original and you depleted multiple times over its life.
sounds to me like there is blown fuse somewhere you are missing.

 

Does your auto dimming mirror work as well?

Agreed. I would pick up a test light and double check the fuse. One may have a hairline crack that you can't see with the naked eye.

 

Soo.. just to update yall, everything's back to normal. The 2nd batch of issues was because of a boneheaded mistake I made.. I put one of the fuses back in the wrong location, i miscounted the blanks and accidentally put one of the fuses into a slot that was supposed to be empty. Thank god for the fuse diagram on the fuse box lid, or I would've never been able to figure it out. Who knew that one fuse linked so many things together? (ACC dash light, clock, garage door opener on rearview, remote/keyless entry, slip indicator light, odometer trip memory)

As for the nav screen.. I bought a new battery but before I swapped the OEM one, I read somewhere in the forum that if I pulled off the ground terminal and left it off for 10-15 minutes, then reconnect it, the screen would come back to life. I tried this, and lo and behold... the screen came back on.

I ended up swapping in the new battery anyway... and man, it was more of a pain than I thought.. there's this plastic casing/harness around the battery that was fastened to the positive terminal cable, which was a pain to take off.. and when I took that off, I realized the OEM battery didn't have any handles or even ears to lift out. It's literally just a big brick of a block with the two terminal posts sticking out of the top. There wasn't enough clearance for me to stick my arm underneath to lift it out either, and the thing's pretty heavy.. so I had to use the terminal posts as part of the grip and pull it out.

Anyway, everything's all good now.. but now I'm thinking that there may not be anything wrong with my OEM battery.. so I'm hesitant to bring it in for the battery core recycling refund ($12).. wonder if I should just return the new battery since the OEM still seems to have some life in it.. ugh I'm also reluctant to swap it back in because of how much of a pain it was to take out, lol. But anyway, I'm just happy everything's good again, was pretty lame having to use the mechanical key to get into my car every time, kept worrying about missing the keyhole and putting a scratch in the paint too.

Thanks to everyone who offered their opinions & suggestions! Much appreciated

 

I have a question for ya'll, if the battery dies and you need to recharge the battery to get to costco or autozone for a new one. How should you recharge the battery without causing damage to the electrical system on our cars?

 

You could disconnect the battery from the car, then charge it if you want. When I worked at a Lexus dealership we would just hood up a battery charger and let it charge with no issues.