Battery message in mfd
#1
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Battery message in mfd
Started up the car today that hasn’t been driven in about 2 weeks. Car was locked during the time. Upon start up I got a message that read something along the lines of battery in reserve or safe mode during parking or something like that. I have never seen this message before and don’t remember it being posted in the 991 forum. The car was in the garage as it always is. As I was backing out, the battery volts went to normal and driving it and parking for a bit a few times was no issue. Is there a way to retrieve the last messages that pop up in the mfd?
Any thoughts? Thanks in advance.
Any thoughts? Thanks in advance.
#2
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You might want to run a test on the battery. You might be near its end of life. I am about to do so on mine with that TOPDON BT200 I bought last fall since my original battery has gone through 9 full years of service.
You might be able to if you connect a diagnostic tester to the vehicle. Sometime past codes are stored if they were not erased.
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DR911s (06-20-2024)
#3
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Thanks…I’ll shoot the service dept foreman a message. He likely has seen this and make a recommendation. Having the battery checked is always a good idea. Getting stuck in a remote location makes for a lousy day.
#4
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I've never been a true believer in those quick battery tests (they are good for shops and garages because they are quick) compared to a real load test and capacity test that I used to do in the lab, but being a tool hound, I decided to get one of these, a TOPDON BT200 from Amazon.
Yesterday, I ran a battery test on my original 8Y 10M old Banner battery. No doubt after that amount of time, it'll be a bit tired compared to day-one.
2024-03-24 16:11:54
Health: 75% 694A
Charge: 100% 12.63V
Intenal R: 3.30 milli-ohm
Rated: 800A EN
Battery test done last September 2023...
Yesterday, I ran a battery test on my original 8Y 10M old Banner battery. No doubt after that amount of time, it'll be a bit tired compared to day-one.
2024-03-24 16:11:54
Health: 75% 694A
Charge: 100% 12.63V
Intenal R: 3.30 milli-ohm
Rated: 800A EN
Battery test done last September 2023...
Last edited by IXLR8; 04-03-2024 at 05:45 PM.
#6
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It is a BT200. I think the BT100 is the same but covers 12V which is all we really need. The BT200 covers both 12 & 24 V batteries and it was on sale at the time at Amazon, so I grabbed it.
Reliable? You mean accurate?
Normally to test a battery, I would do a load test using a 500A carbon pile lead tester, the type you would get at Harbor Freight or Amazon. It won't give you an internal resistance value but if it passes based on battery voltage drop at 1/2 the CCA, that is an indication it is good or bad.
The other test is a capacity test and is quite time consuming and most would not justify the cost of a Megger Torkel 840/860 or whatever replaced that unit now. So now you know why they have these quick and easy battery testers, plus they take up a heck of a lot less room. I'd buy it again.
I've run it on the batteries of my 5 vehicles. The battery on my motorcycle that went last year showed a ridiculous 76.92 milliohms on a 230A SAE battery. The new replacement was 11.36 milliohms. Take readings a few times a year and look at the trend. The higher the CCA, the lower the internal resistance has to be. Notice the internal resistance shown in the post above.
Maybe see what reviews YouTube has.
Reliable? You mean accurate?
Normally to test a battery, I would do a load test using a 500A carbon pile lead tester, the type you would get at Harbor Freight or Amazon. It won't give you an internal resistance value but if it passes based on battery voltage drop at 1/2 the CCA, that is an indication it is good or bad.
The other test is a capacity test and is quite time consuming and most would not justify the cost of a Megger Torkel 840/860 or whatever replaced that unit now. So now you know why they have these quick and easy battery testers, plus they take up a heck of a lot less room. I'd buy it again.
I've run it on the batteries of my 5 vehicles. The battery on my motorcycle that went last year showed a ridiculous 76.92 milliohms on a 230A SAE battery. The new replacement was 11.36 milliohms. Take readings a few times a year and look at the trend. The higher the CCA, the lower the internal resistance has to be. Notice the internal resistance shown in the post above.
Maybe see what reviews YouTube has.
#7
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Chatted with the foreman and he recommended putting the car on a battery maintainer. I was driving the car somewhat regularly but in the past year the work situation is not ideal to drive the 911 to work. I’ll hook that maintainer up and see how it goes.
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#8
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Thanks to you battery nerds, I bought that tester and ran it on my 2016 Banner. I had suspicion it was starting to go due to recent rear tail light faults that were not there. Results were correct
I got a Duracell H6/800 from Batteries Plus near me and they installed it NC. Of course I tipped the guy. Now I can hear how bad that battery was when I start the car. It turns so much faster, that Banner was toast and about to leave us stranded. Thanks again for the insight you all provide.
I got a Duracell H6/800 from Batteries Plus near me and they installed it NC. Of course I tipped the guy. Now I can hear how bad that battery was when I start the car. It turns so much faster, that Banner was toast and about to leave us stranded. Thanks again for the insight you all provide.
#9
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Bit late to the punch here, but that MFD message is stating that the battery low voltage disconnect had been triggered to save your battery from getting too low. It's either your battery starting to show its age, or you have developed a parasitic drain.
A maintainer will only mask the actual problem.
A maintainer will only mask the actual problem.
#10
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Spot-on and something I have said all along on various forums. I never believed in leaving a charger/maintainer connected 24/365 unless you tend to forget to check the battery voltage or have some accessory that draws current all the time.
The only time I use a charger/maintainer is during winter storage and even that is rare because I prefer to spot-charge my batteries and then disconnect them. When I see the battery voltage drop to 12.5V (no less), I'll reconnect the charger for a few hours. I just checked my 14 Ah AGM motorcycle battery that I disconnected 28 days ago and it is still sitting at 12.9V.
The only time I use a charger/maintainer is during winter storage and even that is rare because I prefer to spot-charge my batteries and then disconnect them. When I see the battery voltage drop to 12.5V (no less), I'll reconnect the charger for a few hours. I just checked my 14 Ah AGM motorcycle battery that I disconnected 28 days ago and it is still sitting at 12.9V.
#11
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Original battery from February 19 build. No signs of starting difficulties. Only had that message once. I have not been driving the car as much over the past many months and when I have they have been shorter trips. The day it happened took it for a long drive and then a longer one since then and all seems good and strong.
What is a reasonable voltage for the factory battery with car off? Thanks!
What is a reasonable voltage for the factory battery with car off? Thanks!
#13
#14
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My original battery is a Banner 999.611.080.12, 80ah 800A. Label says VRLA. No obvious AGM sticker like I have seen on some other Banner batteries. Cross referencing the part number brought me to this site
https://www.design911.co.uk/p/car-ba...m-porsche-oem/
Seems it is an AGM. Other sites just link to Porsche parts dept sites that don’t specify AGM. The NOCO charger requires that I choose battery type. Just want to verify before is before put it on a charger. Thanks!
https://www.design911.co.uk/p/car-ba...m-porsche-oem/
Seems it is an AGM. Other sites just link to Porsche parts dept sites that don’t specify AGM. The NOCO charger requires that I choose battery type. Just want to verify before is before put it on a charger. Thanks!
Last edited by Jack F; 04-07-2024 at 03:02 PM.
#15
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What do you mean by "quite a bit higher". I always check displays against the source using my Fluke 88. And from what I remember (and I'll measure it again), it was either spot on or off by 0.1V.