Dead Key Fob, No Problem: How to Start Your BMW When the Key Fob is Dead
Reviewed/Verified by:
Is your BMW not starting because the key fob battery is dead? You can still get in and start it: the fob hides a metal key for the door, and the car can read the fob’s chip at close range even with a flat battery. The steps below cover push button models and older models with a key slot.
At a Glance
- Slide out the emergency metal key and unlock the driver’s door; the alarm may sound.
- Hold the fob against the key symbol on the steering column or the marked console spot.
- Press the brake and the Start button; the car reads the fob’s chip even with a dead battery.
- Replace the fob battery afterwards (CR2032 or CR2450 on most keys).
- If it still won’t start, the car’s battery may be the real problem.
- A scanner such as the YOUCANIC UCAN-II Pro reads the BMW access and immobilizer modules if the car still will not start.
Symptoms
- You can’t start a BMW with a key.
- The BMW key battery is dead, and I can’t start the car.
- The Comfort Access key does not work
How to Manually Start BMW
Step 1
Remove the emergency key blade from the key fob.
Locate the small release button or lever on the back or side to remove the emergency key from a BMW key fob. Once you have located the release button, gently press it or move the lever to release the key. The emergency key should slide out from the key fob. In some models, the emergency key may be stored inside the key fob and requires pressing a button or opening a panel. Be sure to carefully handle the key fob and emergency key to prevent damaging the delicate electronic and mechanical components.
🔧 Find out what is actually wrong before you pay someone to guess
Dealer level diagnostics at home with the YOUCANIC UCAN-II Pro.
- ✔ Covers most makes and models, including many luxury brands. Send us your VIN and we will confirm your car before you order
- ✔ Reads every module, not just the engine, so you find the faults a basic reader says are not there
- ✔ Commands the car: test a fan or pump, bleed ABS, retract an electronic parking brake, register a battery
- ✔ No subscriptions. Free lifetime updates, so the price you pay is the whole price
- ✔ Backed by real mechanics in the USA you can email before and after you buy
Featured in The Wall Street Journal
Step 2
Unlock the driver’s door with the metal blade. (Alarm may go off.)
Step 3
Place the key into the ignition slot.
If your BMW doesn’t have an ignition slot, hold the key fob (not the metal blade) against the marked spot on the right side of the steering column; look for the key symbol. On many newer models the spot is instead in the center console, often marked in the cup holder or phone tray.
Step 4
Press the brake pedal, then press the start button to start the engine. If you hear a click from the engine or the engine is not turning over, there is a high probability the main car battery is discharged.
If your BMW doesn’t start, the key isn’t recognized. A check control message may appear on the dashboard stating the key was unrecognized. Your key may be defective, or the ignition module has a problem.
Tips
- Radio transmission can interfere with the frequency of the BMW key. Also, electronic devices in your pocket or charging in the car can cause interference with the keyless key fob.
- Use a BMW diagnostic scanner capable of reading BMW-specific fault codes to read DME fault codes via the OBD2 port under the dashboard.
The YOUCANIC UCAN-II Pro can read fault code through every control module on supported vehicles, including the DME module.
This guide will assist you if the key fob batteries have died or the key fob is not working. If the main BMW battery has died, follow this guide to get into the car, then follow the instructions in this guide to jump-start a BMW with a dead car battery.
Check these troubleshooting and repair guides for more help on your BMW.
Yes I have a 2007 525i I lost the key order a new one from the dealer and it does not work I charge the battery in the car I was wondering if the key Bob battery might be dead it has a rechargeable battery in it so you can’t just change it what to do the dealership said that you need to bring the car in and it’s either the key or the car and they’re going to charge me the diagnostic to my other key was working fine it has to be the key I guess what BMW does that make extra money someone please give me an answer on how to correct the problem without spending another $500
The dealer after market keys will fail not if but when
I have a similar issue. I got a mobile start put in 2 years ago and have on occasion had the car not recognize the key…after a few tries it usually would work. Recently it stopped recognizing the remote entirely. Neither my main or the spare will get any lights to light up. They both unlock, lock and open the trunk but nothing in the ignition recognizes them. Suggestions? Car is a 06 330xi E90
Having the exact same problem as you guys, have a 2005 E60 520d. Lost my 1 and only fob, ordered a new one through BMW (wakefield) Got it to the car, put it in the keyfob slot, a picture of a orange key come up with a line through it… Tried it again, nothing on dash, no sign of any response what so ever. Bmw have told me its either the key or the car…..
But i left my car unlocked at the time of losing the key for about 5 days until i got the new key, now after reading a few forums some people say that the car is not shuting down into standby mode or what ever and may have drained the battery. The indicater is green on the battery, but got a battery charger (trickler) to see if it makes any difference. I know its not the car as my old one worked fine without any issues. Reading through the comments im wondering if this is a procudure bmw pull to rake in extra money. On purchase of the replacement key, was told it would code itself to the car using the chassis….
Hi
I’ve a problem with my BMW key is 320d 2005 auto
My battery gone flat so I took apart the whole key change the battery on the weld it back
Worked 5 6 time open and close and stop working again
The battery is new .
I have a 2015 3 Series BMW that I lost my key pod to. I ordered another from the Dealership, this does not start my vehicle. I called back to the Dealership and was told to tow the vehicle in and the cost for diagnostic would be 145.00 plus145.00 to program the key pod. On top of just paying 374.00 for the key.
I can’t start my BMW 118i ,n it locks the door n the mobile key doesn’t work I can’t open or close the doors , PLS help I tried to start but it doesn’t show anything on the dashboard
Same here. Wondering how long does the battery last?
What was the resolution? I am having the same problem.
I have a bmw 328 xdrive my car is not working I replace a battery many of time but it show again replaced your battery
Where did you buy the key?
I tryed to program another key fob with my original key now it will not start my 2007 BMW 530i . I have power everywhere but will not do anything when I go to try and start it . Please help me .
My 06 330i will not do anything when the fob id in the slot. The park indicator light stays on all the time now