Died on Freeway - What are these codes? - Solved - Locked Engine… ugh!

Decided to take it home. Now it’s acting like it’s a low battery, yet two of my jump box’s won’t start it. Have it hooked up to my battery tender now, showing 12.6 v. when I put the car in accessories mode, I get the Low Battery message. Ugh!

OEM BMW battery with 4/2021 date. My drive belt (serpentine belt) is still intact.

@Attacking Mid thank you for the response. Are you saying I need to attach a jumper cable from this binding post to another area in the engine bay?

Haven't got around to testing the ground strap(s) yet. Decided to charge the battery with my 4amp AGM charger for the past 20-22 hours.

Noticed this morning the light wasn't green like normal. The charger was showing 13.3-13.7 (which is normal) but the battery gauge (1-5 bars) just kept flashing between 3-4 bars.

Anyway, this is what I know so far:

Hooked up battery reader =12.9v
Opened door = 12.4v
Turned on Accessory mode = 12.1v
Turned to Run (not start) = 12.0v

After 20-30 sec of being in Run mode, the car defaulted back to Accessory mode

New battery, phantom drain, or something else? The battery is OEM BMW and less than 2 years old (4/2021 build date)

Had this happen on my MB S-Class. Had a newer battery, started having similar challenge. Went and bought another new battery (AGM), worked great for two days, then same issue. Discovered later, the cars amplifier wasn't going to sleep and was pulling like 1.5-2.0 amp draw.

Any help would be awesome.

I'M a knucklehead. Was reading the negative battery terminal wrong. It's very hard to read, but I think it says 19/16. I thought it was 19/21.



BMW wants $300 for new one. What brand should I get? Also, rusty at registration, but have the right programmer.

A good place to find good prices on AGM battery is rockauto. They can ship the AGMs. Replace with the same "ah" as what was coded for your X5 &no additional coding is needed. As far as registration, several obdll Bluetooth dongles will work with phone apps to register. FYI, all registration does is erase the last 5 days of 'state of charge & records the replace/installation date & miles on your key so dealer tech can read it. Your car will function ok without registration as it will be recording over the last 5 days of 'SOC'. It's important to code the replacement battery if it doesn't match original so the alternator will charge the new battery correctly. You can always replace with a higher AH battery but don't go less if you don't register as long as you stay within 5-10 AH. This is just my opinion &not others.Please do asy you fell is right for you. Many videos on this on YouTube. Good luck & safe driving.

No dice! No way something as easy as a new battery would help And yes I registered the new battery

It's as if the motor sounds like it's stuck. Just like it's halfway turned over and quits. No ticking, knocking, or multiple attempts to turn. Just a quick r... not a rrr. and that's it

Also tried the jumper cable trick on a few different areas of the engine (motor mount bolt and same bolt as braided ground wire) attached to the negative jump point.

Only codes showing active, is steering wheel angle, which is a given that I disconnected the battery... or the fact I turned the steering wheel super hard when trying to push it in my garage.

What should I try next?

One thing I did notice different, is when I open the door, the instrument cluster used to light up, but now doesn't. all the windows work, headlights turn on, idrive functions, instrument panel comes on when in accessory mode/run.

How long have you owned?
N55's are prone to rod bearing failure if oil pump isn't primed after OFHG replacement or oil cooler work. Rod bearings wear, then spin and jam crankshaft making rotation difficult or impossible.
Put wrench on crankshaft pulley and try to turn over. Only rotate CW looking afront of engine.

Addictive ShoppeRx said:

With spark plugs still in and belt off. Used about 300 ft-lbs on the crankshaft and wouldn't budge 😭 FMl!

Click to expand...

That's very bad, sorry to read.

Unfortunately, that sounds like an effect of that weeping injector(s) you'd had: oil dilution. Direct injectors of all makes tend to be more problematic, but gas is worse than diesel. It'd be worth sending in an oil sample to know for sure.

I guess you'll just have to LS-swap the car now.