Hello again,

I have been following the recent post on the Check Hybrid System Error @Hues10 as it relates to to the 12v battery and wanted to start a new thread so I don't get in trouble. So, for those who haven't read the previous thread, here is my story. I am having either too much drain on my 12v battery or it is not charging correctly. I purchased the Bluetooth battery monitor to see what the battery state is resting and driving. I am getting 12.6v at rest after driving. After putting the car into Ready mode, the monitor does not read 14.4v, instead it climbs oh so slowly. Recently I have shortened my commute to 10 mins. I do have to use a 4amp charger to get the battery back to 12.6 or higher (highest I have measured is 14.4 after trickle charging) if I let the car sit more than a few days. Today I watched the monitor as I drove home, it very slowly climbed to 12.94 v as I drove home. Why is it not showing a much higher voltage with the car in Ready as it should be charging at a much higher rate? I am going to attach some screen shots of the battery monitor if I can figure out how to get one of the longer history. Right now it is only allowing me to do a screenshot of the status page.

 

I believe you're overthinking what the 12 volt battery should be reading when driving - an also after being charged by the car's charging system.

Your trickle charger is quite different from your car's charger. And your battery is a 12 volt battery, not a 14.4 volt battery!

If your 12 volt battery is delivering anything in the 12 volt range before the car is started and being charged by the car's charging system, that is acceptable. If you see anything more than about 13.5 volts when driving with the car's charging system charging the battery, that is acceptable. The 12.6 volt you see soon after driving and stopping is perfectly in the range of what you should expect - nothing higher... My 12 volt battery load tested at 12.63 volts about 15 minutes after it was being charged by the car's charging system (see the analysis directly below).No one was expecting it to be at 14 volts or more after being charged by the car's charging system!





.

 

@bclexus You said in post #55 of the Check Hybrid Thread that it should read 14.1 or so when driving. Also, why would you say not to tend the battery when it gets so low it will not activate the HV to start the car? I've almost been stranded twice now.

I still have to change out the computer behind the glove box when I get time. Maybe that is the culprit of too much parasitic draw.

 

Yes, my voltage that charges the 12 volt battery reads 14.1 volts - 14.2 volts when the ICE is running.

Your 12 volt battery should never get so low it won't power up the accessories, including activation for MG-1 to start the engine using the traction battery. Thus, you should not 'have to' ever use a battery tender.

You obviously have a battery with either a bad cell or something is draining a good battery down to a level that makes it untrustworthy and essentially worthless.

 

I have created a 12V battery monster it seems. I too have the battery monitor now, and can confirm that while driving, the battery level shows over 14. Normally up to 14.5. I too have only a short 10 minute drive to the gym and back. So I check the battery level in the morning before I go. It is usually between 12.5 to 12.6 level, which I accept as being charged. If it dips below 12.4, I will put a tender on it. I guess I should measure the daily drop in it if I do not drive. It is funny to watch the battery level drop if you open the door, or even trunk, as the accessory lights kick on. But it goes back up fairly quickly.

 

@Hues10 - It truly is a 12 volt battery, you know! So, it's not going to maintain the higher voltage level it has while actually being charged. Anything at or above 12.0 volts is perfect.

Don't expect the battery to maintain anything close to a 100% State of Charge level after sitting for a while. A 40% - 50% State of Charge level is perfectly okay after sitting uncharged for multiple hours, including multiple days - because a 40% - 50% State of Charge level provides 12 volts - as you know it is a 12 volt battery! Right?

Don't expect a 12 volt battery to maintain a voltage greater than its cell makeup with each of the 6 cells producing approximately 2.1 volts (a 12V battery is actually a 12.6V battery).

Expecting a 12 volt battery to maintain a voltage greater than 12 volts would be like asking a 12 ounce drink glass to adequately hold more than 12 ounces - or a tightly packed 5lb bag of sugar to adequately hold more than 5lbs. Ain't gonna happen is it?

A 12 Volt battery has six 2.1 volt single cells in series producing a 100% fully charged output voltage of 12.6 volts. Actually each cell is 2.12 volts - so times 6 cells equals 12.7 volts.

If you ever see a 12 volt battery drop below 11.5 volts it is a weakly charged battery that might be getting toward the end of its useful life - - but only if the battery drops below 11.5 volts relatively soon after having received charging that brings it up to at least a 40% - 50% State of Charge level of (wait for it) 12 volts!

 

Totally believe you BCLexus. But this morning, the battery monitor read 12.36 and was in the red zone saying it was low. So I stuck the tender on it. **** and unnecessary, probably. But maybe our AGM battery is a little different with the parameters on state of charge from shown above. Since my driving is much different now with shorter 9 minute drives for 6 miles each way, I don’t think the battery is able to get fully charged up if I don’t drive for a couple of days. At least I am saving on gas.

 

@Hues10 - A sitting 12 volt battery (a 12 volt battery mind you) that is reading 12.36 volts is nicely charged up! It's actually charged to a level above 12 volts, right? That battery is charged to a state of charge that is about 75%, pushing close to its 100% voltage of 12.6 volts determined by its cell makeup of 6 cells times 2.1 volts, which equals 12.6 volts.

 

Don’t disagree with you, but the battery monitor itself is saying that at 12.36, the charge level is at 63% and shows as a low power symbol reading. I just want to get it back to above 12.4 or more since I do not drive far enough normally on a daily basis to get it charged to the full level of 12.61. The battery seems to lose .05 volts per day, so it would only take roughly five days to go from a full charge to below 12.4, and thus show as low per the battery monitor. Most people that drive the car daily for probably 30 minutes or more, never have to worry about the 12V battery not being nearly full when they go to start it. Plus it gets me used to when I am going to get a PHEV or full electric vehicle, and will have to charge it at home on a daily/nightly basis. Thanks for recommending the battery monitor. Saved me from having to hook up a voltmeter all the time.

 

@Hues10 - I think you'd be better served with this plug-in monitor (see below). I think after your 'Check Hybrid Message' episode you're running scared.

You might as well be concerned with the toilet bowel water level dropping .00005cm overnight!

 

What? The toilet bowl level drops? Now what do I need? Some automatic toilet water dispenser filler upper contraption. You are correct though. I am being overly cautious on the 12V battery level monitoring and charging exercise. Though I figure it doesn’t hurt it. Hopefully…

 

@spineman - Maybe so! But only if you find that your car has the problematic Network Gateway ECU with P/N 89100-30180 which is known to cause an extended current draw because it fails to go into sleep mode after 20-30 minutes which can drain the battery to a point the battery becomes seriously drained and ineffective. Although if the vehicle is driven daily or multiple times every week or two the battery draining problem may not even be noticeable.

If you do find that you have the problematic ECU in your car it should be replaced with the new version Network Gateway ECU P/N 89100-30181.

The Network Gateway ECU should only take about 30 minutes or so to go into full sleep mode. Then the current draw drops from as high as 0.75 amperes or more down to around 0.02 to 0.07 amperes, which is not going to drain a healthy battery. I think the new version Network Gateway ECU may go into full sleep mode as soon as 10-15 minutes.

Some people have aftermarket equipment like dashcams (that are wired for features like parking mode), insurance-related tracking devices, and Bluetooth devices like DTC scanners permanently plugged into their OBD2 port, etc. that can prevent the vehicle's Network Gateway ECU from going into its designed sleep mode. Those types of devices may not be the only things responsible for not allowing the Network Gateway ECU to go into sleep mode, which drains the 12 volt battery. The vehicle's CAN (Controller Area Network) is a communication system used in vehicles to enable ECUs (Electronic Control Units) to communicate with each other. It's so intertwined that any communication link that remains active should be considered a suspect in keeping the Network Gateway ECU from going into sleep mode.

 

I gave the car to my son and now he is having the problem happen several times a week now. ECU replaced. Battery tested several times and is fine. Even after charging overnight at times he has to press the start button 7-10 times, then it will finally start. I guess we will have to take it to dealer. Scanner reads no codes.

 

Going on 16 months with my one scare of the check hybrid system error message. I still say keeping the 12V battery charged is the reason why the message has not returned. I probably put the slow trickle charger on it every couple weeks to top it off. Still have the bluetooth battery monitor hooked up so I can see the voltage at any time. I sleep much easier at night. 2013 GSH with 82k miles on it. I wonder how long the Hybrid batter will last itself.

 

I have been having him watch the monitor and trickle charge too, but now the problem is different. The car starts fine on initial start but after you park it to go in the store and come out, you have to push the start button several times to start it, or break out the battery jump to get it started, so something is draining and not charging while the car is driving.