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Discussion Starter · #1 ·
Wanted to see if anyone else has had this issue- and if they know the root cause.

It seems like every other day I get in my beast in the morning and I have to reset the date and time. I have nothing pulling power off the battery while it's sitting over night. I assume it's a weak battery- but all other memory settings/ radio stations have never been erased.

Any idea of what's going on?
 

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Discussion Starter · #2 ·
Done some more research and it looks like this is "power save" mode. Assume it means it may be time for a new battery.
 

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I ahve a similar issue except my date and time reset is accompanied by a "high battery drain" check control message. Dealer checked the battery and alternator on first occurance and stated that they were fine. The resetting is now occuring anytime the car is locked for more than 10 minutes. Taking her back to the dealer next week. I'll keep you posted on what they find.
 

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I'm currently having this issue. I suspect mine is because I drive mine very short distances. I'm charging mine right now, and will see if that at least helps for a while. Any chance you drive short distances as well, thus not giving enough time to recharge fully?

Also, I'm getting a Voltmeter and going to check the voltage to make sure things are charging correctly.
 

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I only drive it on the weekends but the distance varies. I put about about 150 miles on it Friday and Saturday but had to reset the time again on Sunday afternoon.

I was hoping PVUM5 would respond since he was going to take his car to the dealership.
 

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I had the same issues.

I did a trickle charge on the battery for 24 hours, and then tested the battery for load. It checked out.

The next am, the same issue- reset date and time and a high battery drain error.

Took it to the dealer, and they determined the battery was dead- STRANGE, since I tested it myself.

I bit the bullet and had them drop a new battery (took a week to get) and reprogram. Just picked it up not even 10 minutes ago.

Let's see what happens tomorrow am when I go to fire it off.
 

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Alternator.....

I had the same issues.

I did a trickle charge on the battery for 24 hours, and then tested the battery for load. It checked out.

The next am, the same issue- reset date and time and a high battery drain error.

Took it to the dealer, and they determined the battery was dead- STRANGE, since I tested it myself.

I bit the bullet and had them drop a new battery (took a week to get) and reprogram. Just picked it up not even 10 minutes ago.

Let's see what happens tomorrow am when I go to fire it off.
Probably going bad....
 

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If you read my post above- I fully charged the battery and did a load test. Load tests only work if the battery has been trickle charged for at least 24 hours.

My dealer got my car at 3:30 in the afternoon, and reported at 9am the next day that the battery was tested and failed. That is less than a full charge time needed to do a load test, from what I know and understand.

We will see if its the battery. Most of these issues point to a power drain from the remote sensor not putting the car to sleep. In which case, I just burned $500 on a new battery I did not need. I am hoping for the best.

Most common causes:

1. TCU – Telematics Control Unit. This seems to be the most likely and common cause for the error you are getting. The TCU is a modular unit. There are at least 4 circuit boards inside the TCU, 1. Bluetooth Module, 2. Cell Phone Board, 3. GPS Interface, 4. Main Controller Board.
Have you had any issue with your Bluetooth pairing or phone?

2. iPod doc. I did not have the iPod connected, did you add one?
3. Comfort Access in the door handles
4. Driver and passenger seat modules.
5. Dead Battery/Cell
 

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My problem all started with the 'High Battery Drain' message, but it's always turned right over. I did some research on that message and it seems like the main cause is a bad comfort access sensor, usually passenger side, according to other posts. I don't have any accessories hooked up like V1 hardwire or IPod cable, the only thing that is not factory is the previous owner installed a DVD system for rear seat, which I took out, but I left the plastic wire taps that he installed, nothing is hooked up to them. Then recently (last two weeks) I am having the problem with resetting the time about 3 times in two weekends of driving.

Let me know what you figure out and I hope you didn't buy a battery for nothing too!
 

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Yes, Interstate is good and has a good warranty. You will need to get the battery registered in the ECU to ensure it maintains proper charging profile for a new battery versus an aged one.
 

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had the same until i replaced my battery.
 

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Should my battery be dead at 35k?

I just started having the date and time reset and after reading the posts if seems like the battery is the root of the problem. My beast only has 35k on it.

Should the battery be going dead with so few miles?

Thanks for the help guys cherrsagai
 

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I trickle charged for 24 hours and problem went away...

Sent from Samsung Galaxy Tablet via Tapatalk
 

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I just wanted to let everyone know that replacing the battery may not solve the issue.

I replaced my battery last Friday with BMW AGM battery, had it registered to the car. Saturday morning still got the high battery drain message, monday morning had to reset the clock. I took it back to the shop and they ran tests on it the last two days and have determined that I have a bad comfort access sensor.

Hopefully yours is just the battery becuase the sensor is $400+ without labor:eek:oohhh:!!!
 

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I trickle charged for 24 hours and problem went away...

Sent from Samsung Galaxy Tablet via Tapatalk
I lied. Went out today, started it, and the date/time reset. Hmmmm....I have driven very little, the last few days, so maybe too short of a drive. I still need to check the voltage regulator as well.
 
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