getting the convenience functions disabled message....
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porsche
getting the convenience functions disabled message....
hey all i just started to drive the e55 after having it in storage for 6 months....i tried to trickle charge the trunk battery but i wasnt noticing it get to anywhere near 100%. when i start driving the vehicle its showing that convenience functions disabled often now. ive only driven it 2 days for a few 20 minute trips, would driving it for a few hours in one go help this for the alternator to properly charge battery? is it possible the trickle charger did something to the battery? any other tips?
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From: MA
2008 E350 4Matic, 2011 E350 4matic
Put it on a real battery charger with at least 8-10 amps. Trickle charger might not have enough power to fully charge up the battery. Don't forget to also charge up the aux battery.
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porsche
i think it was on a high end charger that has enough juice to jump start a vehicle so i dont think it was an issue of not having enough power, it wasnt a trickle charger i think it was the noco g26000 so its quite powerful
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From: In the Shadow of the Tetons
2013 ML350 Bluetec
high end charger notwithstanding, if it is set to trickle charge but the battery is way low you may not get there. Put it on a fast charge for a couple of hours first.
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'99 and '05 E55 AMG
A failing auxiliary battery can also cause the message. Put an automotive battery tester on both batteries and you won't have to guess. You can buy a decent tester for under $50 off the internet. Be sure to obtain one with a 100 to 1100 CCA capacity minimum. The auxiliary battery should be rated at ~200 CCA and the main rated at 900 CCA.
FWIW, I started getting the convenience functions disabled message and tested both batteries. The auxiliary was rated at 200 CCA but tested at 107 CCA. Rear rated at 900 CCA and tested 790 CCA. Replaced the auxiliary battery last August and haven't had a warning message since. EDIT: The BCM does monitor the health of the auxiliary battery and will throw the message if the auxiliary battery is weak.
Here's one example:
FWIW, I started getting the convenience functions disabled message and tested both batteries. The auxiliary was rated at 200 CCA but tested at 107 CCA. Rear rated at 900 CCA and tested 790 CCA. Replaced the auxiliary battery last August and haven't had a warning message since. EDIT: The BCM does monitor the health of the auxiliary battery and will throw the message if the auxiliary battery is weak.
Here's one example:
Last edited by bbirdwell; Nov 4, 2019 at 10:11 AM.
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porsche
oh ok good info, today while i was driving i had a device that tested the battery power, it was showing 14-14.1 volts while I was driving. It was showing 11.7 volts when the engine was shut off. Are those normal readings?
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From: MA
2008 E350 4Matic, 2011 E350 4matic
Yes those are normal. You can also get the voltage displayed on the dash. With the engine off, switch to the temperature display and then hit the reset button 3 times. That will display the voltage. Once it's displayed you can start the car and the voltage will jump up, you have to be driving or give it a little gas in order for the voltage to go up to 14+. But I believe that just does the main battery, not the aux battery. You need to make sure the aux battery is fully charged. Also 11.7 is a little on the low side but it's still acceptable if it's cold where you are. Those battery low messages are triggered when the voltage drops below 11.
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From: MA
2008 E350 4Matic, 2011 E350 4matic
This comes up a lot. State of charge refers to a battery at rest and typically at 70 degrees with no load. That is not the case with a battery still in the car and with colder temperatures out there. Voltage drops once it's connected to a load so the actual no load voltage of an 11.7 voltage battery will be higher and of course the voltage is also going to be higher at room temperature. Then you can use that state of charge chart. You could also say that 11.7 is probably slightly discharged too. If you fully charged the battery and let it sit for a little while afterwards with no load and then check the chart, that would be one way to tell how much life it has left. Or get a free load test at an auto parts store. In the winter, mine reads as low as 11.5 volts, but that's under 30 degrees. Last time I fully charged it, I think I had it up to 12.5.
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porsche
thanks for the info...the problem is its giving me those readings but everytime i start the car i get that message convenience functions temporarily unavailable....then 1 minute later with engine running it becomes available again.
should i just try to trickle charge the front battery??
should i just try to trickle charge the front battery??
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From: MA
2008 E350 4Matic, 2011 E350 4matic
thanks for the info...the problem is its giving me those readings but everytime i start the car i get that message convenience functions temporarily unavailable....then 1 minute later with engine running it becomes available again.
should i just try to trickle charge the front battery??
should i just try to trickle charge the front battery??
