Remote FOB needs reset every day even with new battery
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Joined: Sep 2007
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From: Sydney Australia
W205 C250BT & R320cdi-L V251 (sold c220 cdi Elegance)
Remote FOB needs reset every day even with new battery
Hi,
Recently I have replaced my CR2025 remote battery as the W205 was reporting low battery.
Subsequent to that I am finding that i have to remove the remote battery and re-install it for it to become visible to the car.
It will immediately work, but again repeat with the same issue in a day or 2.
Any thoughts on what may be the cause?
Thanks in advance.
Recently I have replaced my CR2025 remote battery as the W205 was reporting low battery.
Subsequent to that I am finding that i have to remove the remote battery and re-install it for it to become visible to the car.
It will immediately work, but again repeat with the same issue in a day or 2.
Any thoughts on what may be the cause?
Thanks in advance.
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From: Cheshire UK
C200
The difference is the thickness - 2025 is 2.5mm thick, 2032 is 3.2mm thick.
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Member
Joined: Oct 2019
Posts: 145
Likes: 32
From: Cheshire UK
C200
MBWorld God!
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no worries at all thanks for confirming for us all. Do you think you want to switch to CR2032? I am considering if it is worth it with the extra thickness for longer battery life which means the cover might stick out a little.
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MBWorld God!
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Not sure, CR2025 is what my dealership puts in back when I had PPM here in Canada and so that is what I did. I don't recall seeing it specifically saying it is CR2032 but that is probably because I didn't actually check before putting it in.
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From: San Francisco Bay Area
2019 C63CS
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Interesting, let me grab my key and check, if there are no changes for the facelift I am surprised why my dealership puts CR2025 in it then. Does the new key fob consume more power or they design it so a CR2032 will fit better? I would think the new key fob actually consumes less since the key deactivates during inactivity but not sure when it is active it actually consumes more than the older key.
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Out Of Control!!
Joined: Nov 2018
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From: San Francisco Bay Area
2019 C63CS
In that case I'd recommend trying a new battery. Unfortunately with batteries you never know how long they've been sitting on a shelf and whether they were always stored at proper temperatures. It's not unusual for new batteries to be bad already. I also believe the CR 2032 is more common than the CR 2025, so the latter might be sitting on shelves longer.
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In that case I'd recommend trying a new battery. Unfortunately with batteries you never know how long they've been sitting on a shelf and whether they were always stored at proper temperatures. It's not unusual for new batteries to be bad already. I also believe the CR 2032 is more common than the CR 2025, so the latter might be sitting on shelves longer.
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From: San Francisco Bay Area
2019 C63CS
It seems his key fob stops working within a day or two, so if the key fob no longer communicates with the car properly then there won't be a low battery warning. Now it could also be an electrical fault in the key fob because it was opened up to change the battery. Maybe a bad contact or something. If a new battery doesn't do the trick, I'd try to clean it out with some contact cleaner spray. There might be debris in it.
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It seems his key fob stops working within a day or two, so if the key fob no longer communicates with the car properly then there won't be a low battery warning. Now it could also be an electrical fault in the key fob because it was opened up to change the battery. Maybe a bad contact or something. If a new battery doesn't do the trick, I'd try to clean it out with some contact cleaner spray. There might be debris in it.
Thread Starter
Member
Joined: Sep 2007
Posts: 210
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From: Sydney Australia
W205 C250BT & R320cdi-L V251 (sold c220 cdi Elegance)
Thread Starter
Member
Joined: Sep 2007
Posts: 210
Likes: 16
From: Sydney Australia
W205 C250BT & R320cdi-L V251 (sold c220 cdi Elegance)
In that case I'd recommend trying a new battery. Unfortunately with batteries you never know how long they've been sitting on a shelf and whether they were always stored at proper temperatures. It's not unusual for new batteries to be bad already. I also believe the CR 2032 is more common than the CR 2025, so the latter might be sitting on shelves longer.
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Is the exact symptoms happening on your other key? If so it might have to do with the EIS module in your vehicle if I remembered what you call that. Usually it is just a software issue if not a hardware replacement might be necessary.
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Joined: Sep 2007
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From: Sydney Australia
W205 C250BT & R320cdi-L V251 (sold c220 cdi Elegance)
I tested both batteries in a tester (identical to this https://www.amazon.com.au/Dlyfull-Un.../dp/B07DPLD6KB ) and both batteries reported well into the GOOD. Infact they were only a notch different.
How ever the issue does not occur with the other FOB, so my next test is to swap batteries and rule out a FOB issue and hopefully close this off as a fickle battery problem.
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Good point!
I tested both batteries in a tester (identical to this https://www.amazon.com.au/Dlyfull-Un.../dp/B07DPLD6KB ) and both batteries reported well into the GOOD. Infact they were only a notch different.
How ever the issue does not occur with the other FOB, so my next test is to swap batteries and rule out a FOB issue and hopefully close this off as a fickle battery problem.
I tested both batteries in a tester (identical to this https://www.amazon.com.au/Dlyfull-Un.../dp/B07DPLD6KB ) and both batteries reported well into the GOOD. Infact they were only a notch different.
How ever the issue does not occur with the other FOB, so my next test is to swap batteries and rule out a FOB issue and hopefully close this off as a fickle battery problem.
