How to get in your McLaren when the battery is dead, and how to wake up the battery.

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0:00 Intro
0:52 Manual entry
2:52 Jack points
4:48 Wheel off
5:36 Fender liner screws
7:07 Manual cable pull
9:16 Access the battery
11:38 Method 1, wake up battery with jumper
13:45 Method 2, wake up battery with charger
14:48 Summary

[@chrisboraston]

Thanks so much!!!!! My 12C (On Mc Battery charger) went lifeless. Could never take wheel off as up against garage wall. Couldn't push car out as brake on. Had been pressing reset button (several times) and gave up. watched your video and learned to push and hold for 5 secs. Car came alive. You just save me thousands! Cheers from England!

[@DeeperImageAutomotive]

I'm really close to pulling the trigger on an MP4-12C and your videos have been helpful in understanding the car. I'm a big fan of DIY, and have worked on Corvettes, Vipers, Subarus, Nissans, among many others, but the McLaren life forums always scare me off lol.

[@McMedics]

Those forums have a lot of great info, and some misunderstood info, and a few kids posing as owners. Look at the date on the posts you're reading. If it's a 7 year old complaint it's probably not valid today.

[@cashfornothing]

NIce video! Keep em coming!

[@ellisjackson3355]

Thanks, good video. Never thought I'd face this problem in my life yet here I am

[@renemacias6356]

Great video! Keep them going. Hopefully, someday you'll be able to show how to remove the service reminder after a DIY oil change/service.

[@McMedics]

That is a dealer level tool function only, unless you "cheat" by just changing the date in the car. That's what many do.

[@renemacias6356]

@@McMedics Thanks for letting me know. Keep up the great work!

[@petermoore9512]

Huge thanks for this - I just used it successfully to retrieve keys locked in the frunk (yeah, one of those stupid things that you think you would never do!). I have a 570S and found a couple of minor differences in the required procedure.

[@McMedics]

Yup it's basically the same, things are in the same spot.

[@bentickner1]

worked like a charm. my battery died because the outlet the charger was in tripped the breaker from another tool. My doors were locked, but luckily the windows dropped before it died. I was able to open the the door with the key (used plier and turned it it back and forth 10degrees to unstick it) unlock is rotating the key toward the center of the car. I also was able to open the door with a coat hanger and bulling the door release red cloth pull (i wanted to see how hard this was). Once the door was opened I pulled the frunk release. As for charging I am glad I watched the video till the end first. the 5second butt0n push worked great to get the charger working.

[@gendronyves6288]

I had the same problem, I used the emergency key for the hidden lock. I thanks you because I did not know by this method for open the frunk

[@AutoAntus]

thanks, i am new at mclaren workshop soo, thanks a lot

[@fastercars2010]

Waking up the battery with a jump is key, yesterday I could not get my 570 to take the charge with the McLaren charger (even doing the Reset button a bunch of times). Might see you again at C&E in Atlanta? I have the Vermillion Red 570S.

[@McMedics]

C&E might not be a thing even this year, but when it's back I'll be back.

[@dr.warner2288]

does the 570s have the same removable rubber liner?

[@McMedics]

The 570 tub comes out all in 1 piece after screws come out. But, to access the battery there is a removable panel so you don't have to do that.

[@MrMB2343]

Hey man, quick question. Why were you taping it to get it 12V and not just leaving it on

[@McMedics]

Surging it wakes the BMS up, but you also don't want to jump start it or surge it with a lot of current as it can damage the battery in rare cases.

[@diogodimas8677]

Why dont people cut the trunk panel to make a "hole" for the battery? Since its plastic, use a plastic cutter to make a rectangular hole, then use tape or another method to hold the cut piece on the original panel, so when the battery is asleep, remove the "new" panel and normal process. Right?

[@McMedics]

This happening isn't a "normal" thing to start with. If the battery is asleep you still have to get into the car, that's the core problem, which doesn't help you with a hole in your trunk. Remember, what wakes it up (if you have a charger) is the charger itself, which doesn't require removing any trunk panel. Starting with the 570s they got wise to it and put an access panel in there to get to the battery.

[@OGCrypto33]

Imagine having locking wheel nuts and the key sits in your glovebox 😂

[@McMedics]

Imagine HAVING a glovebox!

[@odortiz]

i prefer to keep my cars in the garage with the windows open. mostly because it's tight, and i can reach in and pop hoods or parking brakes. perhaps a charging port that is accessible from the outside of the car would be handy in case you need to wake it up with the charger, or a jump pack.

[@McMedics]

I usually do have the window down, sometimes I don't, and this just happened to be one of those times. The last time I had the bumper off I almost did put a charging port accessible from the outside but I didn't find a place I found acceptable. I may revisit that again.

[@MethmalDhananjaya]

If the unlocking manual key cylinder doesnt work, why McLaren put them there in the first place?

[@McMedics]

They think it's supposed to work. It's so difficult to do, people break keys trying. When I changed to soft close latches I tested it, without it connected turned fine but connected to the latch I could never get it to turn.

[@MethmalDhananjaya]

​@@McMedics would be a interesting project if you convert it into a old-school physical latch if you don't care about car's resell value. 😂

[@McMedics]

I wouldn't want that at all! I love the swipe doors, and soft close. Figuring out how to keep the key cylinder working would be great but as little as they're needed not worth the time for most.

[@MethmalDhananjaya]

@@McMedics true, working barrel would be enough.

[@McMedics]

The barrel isn't the issue, that turns quite easily. It simply jams up trying to turn the mechanism in the latch.

[@yeeehaar]

First here! Thanks for the video - hope I never have to use it!

[@McMedics]

I hoped for the same, but I'm glad I had a little knowledge to fix it right away and was able to share this with everyone else.

[@bigmotor3845]

Did you find out why the battery discharged?

[@McMedics]

OBD2 Bluetooth dongle was left plugged in.

[@bigmotor3845]

@@McMedics A good bit of vehicles have come into my shop with the same issue.

[@osx86touch]

@@McMedics ​Holy shit guys, you just helped me realize what has been draining my battery after almost an entire season of confusion. Thank you so much for sharing! I have a BT dongle I use to track rpm and pedal pressure on track days and never bothered to yank it out. I’m going to start the jumping method you showed here since my 570 is not getting any feedback from the charger, even with the reset button tricks. Do you know if any standard booster will do here, even these devices are usually meant to be used for lead acids, or did you use a special one in this video?

[@McMedics]

@@osx86touch Try disconnecting the BMS plug on top first, then hit reset on the charger. If that doesn't work, there is a charger I've used that will wake one up. Otherwise you just want to surge it with anything 12v, just tap it, and make sure the BMS plug is unplugged.

[@osx86touch]

@@McMedics Appreciate the help, I’ll give it a shot with the regular charger after having unplugged the BMS and if it doesn’t work I’ll try that. Do you think something as simple as a 12V wall wart power supply with the leads cut off could do the trick here? I don’t have a booster pack on hand yet. Thanks so much again!

[@acrokos]

I always pop the hood open after each ride, just to avoid all of what you went through.

[@McMedics]

That can actually kill the battery.

[@acrokos]

@@McMedics I should have been more specific, not all the way open, latched close only to have the cable come out to battery tender.

[@McMedics]

Not fully latched can kill the battery, moot if it's on a tender

[@acrokos]

@@McMedics Yes. Been doing this since April 2018 with my 12c. No problems what's so ever. Now I got to figure out why my 650s is throwing off a battery management active error message. I already emailed your side kick ;)

[@BasedBidoof]

The text on this thumbnail is nearly impossible to read on my crap laptop. Just a tip for future thumbnail design

[@Executiveinvestments-]

Where do you get a price of $3K. lol My 720 was $400. Nice lie.

[@McMedics]

Yes, $400 is a nice lie. You can't buy a lithium battery for $400 for any car.

[@Executiveinvestments-]

@@McMedics nice lie? I have my receipt in front of me from the dealer. $400.69. You want to put money on it?

[@McMedics]

You might have a receipt for a lie they told you! They probably charges you $400 to wake up your battery and told you it was a new one. Even the Mercedes battery people try that doesn't work right is $1,600. Aftermarket with no BMS is $900. Check that battery production date vs your receipt, you got taken for a ride.

[@Executiveinvestments-]

@@McMedics makes sense. A receipt that I paid for but its a lie? LMFAO!!! Yeah Mclaren dealer took me for a ride. Makes sense since I seen them install it. Anymore dumb comments broke loser?

[@marcodebordo3695]

That’s not how you do it

[@McMedics]

I just did it in a video, so apparently it is.

[@marcodebordo3695]

Nope, you have a hidden key opener on the left side, you don’t need to take a wheel out

[@McMedics]

You do when the window doesn't roll down. When you use that key cylinder and open the door, the glass will break