Jun 9, 2015, 07:26 PM
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DIY: Smartkey Battery Replacement
Thread Starter
Super Member
Joined: Oct 2007
Posts: 811
Likes: 2
From: Toronto, ON
2011 E350 4Matic Wagon, 2013 C350 4Matic Sedan
DIY: Smartkey Battery Replacement
My car has been giving me the "Replacement Keyfob Battery" error message so I decided to take the key apart to check what batteries are needed. Here's a pictorial guide to the disassembly...
Starting with the key:
First you take out the valet key by sliding the lever to the left:
Locate the slider inside the cavity and use the hook on the valet key to slide it towards the notched side of the fob:
At the same time, push the chrome portion of the end of the fob out (this part takes a little coordination as you are the holding the slider in the open position as well as prying the battery holder out):
Now slide the entire assembly out of the fob:
Turn it over and you will see two batteries:
Batteries slide out sideways under the positive terminals. OE parts are Panasonic CR2025 (3V) x2:
Mec.ca is selling Energizer ones for ca$1.99.
Replacement batteries slide under the positive terminal. Then slide the battery assembly back into the fob. It will only go in one way due to the shape. You will hear a click when it is fully inserted. Slide the valet key back in. And you are rocking again.
Hope this helps!
Starting with the key:
First you take out the valet key by sliding the lever to the left:
Locate the slider inside the cavity and use the hook on the valet key to slide it towards the notched side of the fob:
At the same time, push the chrome portion of the end of the fob out (this part takes a little coordination as you are the holding the slider in the open position as well as prying the battery holder out):
Now slide the entire assembly out of the fob:
Turn it over and you will see two batteries:
Batteries slide out sideways under the positive terminals. OE parts are Panasonic CR2025 (3V) x2:
Mec.ca is selling Energizer ones for ca$1.99.
Replacement batteries slide under the positive terminal. Then slide the battery assembly back into the fob. It will only go in one way due to the shape. You will hear a click when it is fully inserted. Slide the valet key back in. And you are rocking again.
Hope this helps!
Super Member
Joined: Dec 2008
Posts: 651
Likes: 2
From: London, UK
MB W204, VW Polo, Audi R8 V10 - SOLD.
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MBWorld Fanatic!
Joined: Feb 2004
Posts: 3,986
Likes: 6
From: SEATTLE WASHINGTON USA
'08 C300 Lux Barolo Red Beige Leather P2 MM 18" wheels '84 944
MBWorld Fanatic!
Joined: Mar 2009
Posts: 3,135
Likes: 272
From: Sweden
S213
Its one of many thing that is different between EU and US cars.
US cars also:
Is covered with warning labels everywhere
Have an emergency trunk opener
Have driver side knee protection
Has a auto shifter that displays gear with LED.s
have amber front side markers
Have different layout on some buttons
And more I most likely have missed
Thread Starter
Super Member
Joined: Oct 2007
Posts: 811
Likes: 2
From: Toronto, ON
2011 E350 4Matic Wagon, 2013 C350 4Matic Sedan
Vic Viper-- And thanks to the US, we Canadians end up with all that stuff as well. And more... But it doesn't matter as the car is what it is here. If those differences really bother somebody, then buy another car.
And since I have KG, my keyfob is always in a leather sleeve. So I never have to look at the panic button.
And since I have KG, my keyfob is always in a leather sleeve. So I never have to look at the panic button.
Member
Joined: Dec 2007
Posts: 79
Likes: 0
From: Richmond Hill, Ontario, Canada
MB 2008 C300 sport, 2008 Rally blue Subaru Impreza 2.5 SI 1995 MB C280 W202
My car has been giving me the "Replacement Keyfob Battery" error message so I decided to take the key apart to check what batteries are needed. Here's a pictorial guide to the disassembly...
Starting with the key:
First you take out the valet key by sliding the lever to the left:
Locate the slider inside the cavity and use the hook on the valet key to slide it towards the notched side of the fob:
At the same time, push the chrome portion of the end of the fob out (this part takes a little coordination as you are the holding the slider in the open position as well as prying the battery holder out):
Now slide the entire assembly out of the fob:
Turn it over and you will see two batteries:
Batteries slide out sideways under the positive terminals. OE parts are Panasonic CR2025 (3V) x2:
Mec.ca is selling Energizer ones for ca$1.99.
Replacement batteries slide under the positive terminal. Then slide the battery assembly back into the fob. It will only go in one way due to the shape. You will hear a click when it is fully inserted. Slide the valet key back in. And you are rocking again.
Hope this helps!
Starting with the key:
First you take out the valet key by sliding the lever to the left:
Locate the slider inside the cavity and use the hook on the valet key to slide it towards the notched side of the fob:
At the same time, push the chrome portion of the end of the fob out (this part takes a little coordination as you are the holding the slider in the open position as well as prying the battery holder out):
Now slide the entire assembly out of the fob:
Turn it over and you will see two batteries:
Batteries slide out sideways under the positive terminals. OE parts are Panasonic CR2025 (3V) x2:
Mec.ca is selling Energizer ones for ca$1.99.
Replacement batteries slide under the positive terminal. Then slide the battery assembly back into the fob. It will only go in one way due to the shape. You will hear a click when it is fully inserted. Slide the valet key back in. And you are rocking again.
Hope this helps!
i don't get it...can't pull out the chrome part... need help
can anyone post it on youtube and let me know the link?
The dealer want to charge $40 bucks for the damm battery replacement
MBWorld Fanatic!
Joined: Feb 2004
Posts: 3,986
Likes: 6
From: SEATTLE WASHINGTON USA
'08 C300 Lux Barolo Red Beige Leather P2 MM 18" wheels '84 944
Sex and sirens
When sex comes to mind, the last thing I would be thinking about would be my car key.
The panic button does have a use, provided the car does not have TeleAid, and mine does not by choice.
Picture yourself relaxing in a coffee shop, admiring your MB, parked at the curb where you can keep an eye on it. You see an unsavory type stop by the car and you don't like his looks. Pressing the ugly red button sets the alarm siren howling, and the terrorist moves along to bomb something else.
You Euros have plenty to panic about, seems to me.
The panic button does have a use, provided the car does not have TeleAid, and mine does not by choice.
Picture yourself relaxing in a coffee shop, admiring your MB, parked at the curb where you can keep an eye on it. You see an unsavory type stop by the car and you don't like his looks. Pressing the ugly red button sets the alarm siren howling, and the terrorist moves along to bomb something else.
You Euros have plenty to panic about, seems to me.
MBWorld Fanatic!
Joined: Mar 2009
Posts: 3,135
Likes: 272
From: Sweden
S213
When sex comes to mind, the last thing I would be thinking about would be my car key.
The panic button does have a use, provided the car does not have TeleAid, and mine does not by choice.
Picture yourself relaxing in a coffee shop, admiring your MB, parked at the curb where you can keep an eye on it. You see an unsavory type stop by the car and you don't like his looks. Pressing the ugly red button sets the alarm siren howling, and the terrorist moves along to bomb something else.
You Euros have plenty to panic about, seems to me.
The panic button does have a use, provided the car does not have TeleAid, and mine does not by choice.
Picture yourself relaxing in a coffee shop, admiring your MB, parked at the curb where you can keep an eye on it. You see an unsavory type stop by the car and you don't like his looks. Pressing the ugly red button sets the alarm siren howling, and the terrorist moves along to bomb something else.
You Euros have plenty to panic about, seems to me.
Seems like you havnt been to Sweden
LOL!
Senior Member
Joined: Dec 2008
Posts: 312
Likes: 2
C350 Elegance
Peabears,
Thank you kindly, great input. Regards,
JV
Europeans, politics aside the track record is not very convincing as an example of foresight toward oportunistic leaderships. I am sorry to have read about things consumated in such a manner that led to a whole new concept in crimes of lesa-humanitatis without appeal from natives or outsiders. I really would have liked to have a panic button escape to prevent them.
Thank you kindly, great input. Regards,
JV
Europeans, politics aside the track record is not very convincing as an example of foresight toward oportunistic leaderships. I am sorry to have read about things consumated in such a manner that led to a whole new concept in crimes of lesa-humanitatis without appeal from natives or outsiders. I really would have liked to have a panic button escape to prevent them.
Super Member
Joined: Aug 2008
Posts: 552
Likes: 9
From: Homeless
'20 Targa 4 DD, ' 18 Volvo S60 T6
The big red button is a Vanity Button - so when put it on the table / bar it draws attention.
Very clever for MB to disguise this as a Panic Button.
Also used to stop girls in their tracks for 5 secs when walking beside your parked car so you have time to jump out of the cafe chair and chat with them -before they are gone
Very clever for MB to disguise this as a Panic Button.
Also used to stop girls in their tracks for 5 secs when walking beside your parked car so you have time to jump out of the cafe chair and chat with them -before they are gone
Super Member
Joined: Apr 2010
Posts: 667
Likes: 8
From: Boston 'burbs
2018 E300 Lux, 2006 Corvette Z51, 2015 Mercedes ML350 (wife's)
surprised that no one knows the real reason for the panic button-- finding your car in the parking garage after getting off the elevator on the wrong floor lol
MBWorld Fanatic!
Joined: Feb 2004
Posts: 3,986
Likes: 6
From: SEATTLE WASHINGTON USA
'08 C300 Lux Barolo Red Beige Leather P2 MM 18" wheels '84 944
Panic and cost
You do realize, don't you, that if the car has Teleaid (some dopey new name, now) when the alarm goes off the alarm center in Texas is notified and you get a bill. Used to be five bucks on your Visa card.
Newbie
Joined: Feb 2020
Posts: 5
Likes: 0
C300 2008
My car has been giving me the "Replacement Keyfob Battery" error message so I decided to take the key apart to check what batteries are needed. Here's a pictorial guide to the disassembly...
Starting with the key:
First you take out the valet key by sliding the lever to the left:
Locate the slider inside the cavity and use the hook on the valet key to slide it towards the notched side of the fob:
At the same time, push the chrome portion of the end of the fob out (this part takes a little coordination as you are the holding the slider in the open position as well as prying the battery holder out):
Now slide the entire assembly out of the fob:
Turn it over and you will see two batteries:
Batteries slide out sideways under the positive terminals. OE parts are Panasonic CR2025 (3V) x2:
Mec.ca is selling Energizer ones for ca$1.99.
Replacement batteries slide under the positive terminal. Then slide the battery assembly back into the fob. It will only go in one way due to the shape. You will hear a click when it is fully inserted. Slide the valet key back in. And you are rocking again.
Hope this helps!
Starting with the key:
First you take out the valet key by sliding the lever to the left:
Locate the slider inside the cavity and use the hook on the valet key to slide it towards the notched side of the fob:
At the same time, push the chrome portion of the end of the fob out (this part takes a little coordination as you are the holding the slider in the open position as well as prying the battery holder out):
Now slide the entire assembly out of the fob:
Turn it over and you will see two batteries:
Batteries slide out sideways under the positive terminals. OE parts are Panasonic CR2025 (3V) x2:
Mec.ca is selling Energizer ones for ca$1.99.
Replacement batteries slide under the positive terminal. Then slide the battery assembly back into the fob. It will only go in one way due to the shape. You will hear a click when it is fully inserted. Slide the valet key back in. And you are rocking again.
Hope this helps!
MBWorld Fanatic!
Joined: Jul 2008
Posts: 8,384
Likes: 800
2019 G70 6MT & 2022 Ford Maverick XL
