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Discussion Starter · #21 ·
I may of missed it in one of your previous posts, but are you having any issues other than the ESS not working?

As you may recall from another thread, I'm in the same situation as you with a battery that tests good. However, ESS is not working....it says it is in battery protection mode. But everything else works fine, including remote starts with the seat warmer activating as it should.

Its been 2+ months for me and since I hate ESS I'm quite happy with the situation. So as long as my battery continues to test Ok, I'm just going to leave it as is. So it would appear from my experience thus far that I also have a a failed/failing? IBS. The question I have, which may not be answerable right now, is whether the only function of the IBS is to handle the ESS system?
That is the only issue I have. Just that ESS doesn't work. I do tend to like using it though, and I also don't like when something doesn't work as designed or configured, so some of this is a OCD sort of thing.
 

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Tell me you work for the railway without telling me you work for the railroad. I might know a thing or two about locomotives :p

None of the locomotives I deal with use coolant, just plain old water.........and the AESS systems still mess up all the time, like shutting down when its too cold, then having the engine dump it's water, or if you catch it in time restart it and be load limited until it warms up again
I was an electrical engineer at GE working on locomotive prototype development and also on troubleshooting and testing locomotives after catastrophic repairs for 21 years. Every production model with the 'meatball'.

Yes, locomotives run straight water with a nalco rust preventative and AESS sure has it's issues and always will.
 

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I was an electrical engineer at GE working on locomotive prototype development and also on troubleshooting and testing locomotives after catastrophic repairs for 21 years. Every production model with the 'meatball'.

Yes, locomotives run straight water with a nalco rust preventative and AESS sure has it's issues and always will.
Now that's a locomotive!!! Got to see Union Pacific "Big Boy" run through my town a couple years ago. Serious Bada$$ machine!!!😎
 

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Discussion Starter · #25 ·
Just for some comparison of duty cycle of the alternator on the same battery

Fully charged


Drained

That interesting. I actually took a look at the duty cycle on the way home. It was around 15 to 20 percent almost the entire time. The OBDLink software has access to some really good PIDs in it. I have been leaving SOC, voltage just before IBS wakeup, Generator Duty Cycle, Voltage, current temperature. etc. I have noticed the resting voltage is 12.6V, and it doesn't really matter how long I leave it, so I can probably rule out phantom drain. Also keeps me from having to leave the hood popped every time I park it.

Yesterday I tried something new to see if I could force the IBS into calibration mode. I unplugged the sensor, and then started the car. I have left it unplugged, as well as the battery terminals off before and it did nothing, so my though was for the engine computer to know it could not read the IBS, and then see if it would make it relearn the battery. Obviously I got the error messages when it was unplugged, but when I plugged it back in, SOC immediately went to 98% and the ESS worked on the first stop. Then after driving about 5 minutes, the SOC dropped back to 58% like it has in the past. This leads me back to the IBS not working correctly. I also tried the PID that would let me read the calculated resistance provided by the IBS. I was going to compare it to what I had with my battery tester. I did not have a value, so I'm not sure if that was an issue with the IBS, or just one of those that doesn't provide the type of information I would expect. My new IBS gets here on Tuesday, so that will be the true test most likely.

On a side note, I am going to be using the OBDLink software much more often. It pulls way more than even alfaobd can do. There were probably 2 or 3 dozen PIDs just for the IBS sensor.
 

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The question I have, which may not be answerable right now, is whether the only function of the IBS is to handle the ESS system?
This device is also called the "Battery Temperature Sensor", or BTS.

Found this in the service manual:

OPERATION
The BTS is used to determine the battery temperature and control battery charging rate. This temperature data, along with data from monitored line voltage, is used by the PCM to vary the battery charging rate. System voltage will be higher at colder temperatures and is gradually reduced at warmer temperatures.
The PCM sends 5 volts to the sensor and is grounded through the sensor return line. As temperature increases, resistance in the sensor decreases and the detection voltage at the PCM increases.
The BTS is also used for OBD II diagnostics. Certain faults and OBD II monitors are either enabled or disabled, depending upon BTS input (for example, disable purge and enable Leak Detection Pump (LDP) and O2 sensor heater tests). Most OBD II monitors are disabled below 20F.

and...

A battery temperature sensor, located in the battery tray housing, is used to sense battery temperature.
This temperature data, along with data from monitored line voltage, is used by the PCM to vary the battery charging rate. This is done by cycling the ground path to control the strength of the rotor magnetic field. The PCM then compensates and regulates generator current output accordingly.

So it doesn't "handle the ESS system", but given that a battery is either out of spec or the BTS is sensing an out-of-spec battery the ESS is probably the first symptom. A disabled BTS is not allowing optimum charging of the battery, so battery life is most likely impacted. How much? One online site says 10% to 20%.

IMO it doesn't seem like a cost-effective trade-off to live with a defective IBS at the expense of shorter battery life.
 

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This device is also called the "Battery Temperature Sensor", or BTS.

Found this in the service manual:

OPERATION
The BTS is used to determine the battery temperature and control battery charging rate. This temperature data, along with data from monitored line voltage, is used by the PCM to vary the battery charging rate. System voltage will be higher at colder temperatures and is gradually reduced at warmer temperatures.
The PCM sends 5 volts to the sensor and is grounded through the sensor return line. As temperature increases, resistance in the sensor decreases and the detection voltage at the PCM increases.
The BTS is also used for OBD II diagnostics. Certain faults and OBD II monitors are either enabled or disabled, depending upon BTS input (for example, disable purge and enable Leak Detection Pump (LDP) and O2 sensor heater tests). Most OBD II monitors are disabled below 20F.

and...

A battery temperature sensor, located in the battery tray housing, is used to sense battery temperature.
This temperature data, along with data from monitored line voltage, is used by the PCM to vary the battery charging rate. This is done by cycling the ground path to control the strength of the rotor magnetic field. The PCM then compensates and regulates generator current output accordingly.

So it doesn't "handle the ESS system", but given that a battery is either out of spec or the BTS is sensing an out-of-spec battery the ESS is probably the first symptom. A disabled BTS is not allowing optimum charging of the battery, so battery life is most likely impacted. How much? One online site says 10% to 20%.

IMO it doesn't seem like a cost-effective trade-off to live with a defective IBS at the expense of shorter battery life.
Interesting. Thanks for posting.

Perhaps I will have it replaced then as I have an extended warranty. For that matter, if the IBS is cheaper than my deductible I might as well do it myself.
 

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Discussion Starter · #28 ·
This device is also called the "Battery Temperature Sensor", or BTS.

Found this in the service manual:

OPERATION
The BTS is used to determine the battery temperature and control battery charging rate. This temperature data, along with data from monitored line voltage, is used by the PCM to vary the battery charging rate. System voltage will be higher at colder temperatures and is gradually reduced at warmer temperatures.
The PCM sends 5 volts to the sensor and is grounded through the sensor return line. As temperature increases, resistance in the sensor decreases and the detection voltage at the PCM increases.
The BTS is also used for OBD II diagnostics. Certain faults and OBD II monitors are either enabled or disabled, depending upon BTS input (for example, disable purge and enable Leak Detection Pump (LDP) and O2 sensor heater tests). Most OBD II monitors are disabled below 20F.

and...

A battery temperature sensor, located in the battery tray housing, is used to sense battery temperature.
This temperature data, along with data from monitored line voltage, is used by the PCM to vary the battery charging rate. This is done by cycling the ground path to control the strength of the rotor magnetic field. The PCM then compensates and regulates generator current output accordingly.

So it doesn't "handle the ESS system", but given that a battery is either out of spec or the BTS is sensing an out-of-spec battery the ESS is probably the first symptom. A disabled BTS is not allowing optimum charging of the battery, so battery life is most likely impacted. How much? One online site says 10% to 20%.

IMO it doesn't seem like a cost-effective trade-off to live with a defective IBS at the expense of shorter battery life.
Correct. The IBS doesn't control the ESS, but that is the only parameter that is not being met currently. It's failing the battery OK check. The temperature actually appears accurate on it. The only thing I can see that appears off so far is the State of Charge (as well as come of the capacity numbers which is probably driving off the SOC). Its showing in the 50s, when the battery tester is showing in the upper 95s or 100. The battery has a capacity of 74 amps. I put a 30 amp load on it for probably an hour. Even with the that load on, it was still keeping 11.9v at the end. When resting voltage came back up to like 12.1 or 12.2. So at that point is still should have had about 60 percent. SOC in the IBS showed 30%, and was charging at 90A when I restarted it. Over the course of about 3 trips totaling 45 minutes, amps were back down to 4 to 5 amps. SOC still was only showing 60 percent again. From time to time I will throw a batter tender on it, just to make sure it's topped off, and I have always connected directly to the terminals. I probably should connect just behind the IBS as it won't see the current going in. If you look at the lifetime current in vs the lifetime current out, you can see the difference. I'm not sure if it is remembering that in the calculation, which is why I was trying to reset it.
 

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This is an interesting read that might apply...

 
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Discussion Starter · #30 ·
This is an interesting read that might apply...

That is a very good writeup of the operation. I just can't get it into the calibration mode. The only time I thought I had it was when I unplugged just the sensor and started it up, and waiting to get the code. Then I plugged it back in and I could see the SOC was 98% (was previously 56ish%) The 98% matched my battery tester. Then I drove it and at the first stop ESS started working. It shouldm't have if it was relearning. Then started up like normal. About 5 minutes later, I watched the SOC drop back from 99% to 55%. I never had another stop where I could have tested it again before that. All the other parameters stayed the same. IBS current, IBS battery voltage, Generator duty cycle, IBS battery temp, etc. There is a parameter that measures internal battery resistance, but it doesn't show a value. I wanted to compare that to the Battery Tester as that's how the tester determines SOH, so figured the IBS would do something similar. It will list SOH, but does so in mA (vs %), and there were two different ones I needed to add together, so I wasn't going to do that while driving. At this point I'll probably just wait till I get the new IBS on Tuesday, and then give it a shot. If that doesn't check out, I'll drop the battery off at Battery Plus so they can check it the week I'm out of town.
 
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It looks like you are doing exactly what is needed and having Batteries+ take a good look at can't hurt and you've dug up a lot of useful information here. Good luck
 
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This device is also called the "Battery Temperature Sensor", or BTS.

Found this in the service manual:

OPERATION
The BTS is used to determine the battery temperature and control battery charging rate. This temperature data, along with data from monitored line voltage, is used by the PCM to vary the battery charging rate. System voltage will be higher at colder temperatures and is gradually reduced at warmer temperatures.
The PCM sends 5 volts to the sensor and is grounded through the sensor return line. As temperature increases, resistance in the sensor decreases and the detection voltage at the PCM increases.
The BTS is also used for OBD II diagnostics. Certain faults and OBD II monitors are either enabled or disabled, depending upon BTS input (for example, disable purge and enable Leak Detection Pump (LDP) and O2 sensor heater tests). Most OBD II monitors are disabled below 20F.

and...

A battery temperature sensor, located in the battery tray housing, is used to sense battery temperature.
This temperature data, along with data from monitored line voltage, is used by the PCM to vary the battery charging rate. This is done by cycling the ground path to control the strength of the rotor magnetic field. The PCM then compensates and regulates generator current output accordingly.

So it doesn't "handle the ESS system", but given that a battery is either out of spec or the BTS is sensing an out-of-spec battery the ESS is probably the first symptom. A disabled BTS is not allowing optimum charging of the battery, so battery life is most likely impacted. How much? One online site says 10% to 20%.

IMO it doesn't seem like a cost-effective trade-off to live with a defective IBS at the expense of shorter battery life.
In my 2014 V6 TH I have the an X2Power AGM battery all wrapped up in closed cell foam insulation which is aluminized on both sides.
I DO NOT have an IBS or ESS.
So the battery temperature sensor does not know the temperature of my battery, only the ambient engine compartment temperature.
So will having a different battery type and not knowing the actual temperature of my battery cause a battery charging issue? Or any other issue?
I have been using AGM batteries for about 5 years now and I think battery charging has been just fine.
I understand that flooded and AGM batteries have different charging requirements because my battery charger has a setting for each one.
I was hoping my Jeep dealer could change the software installed in my PCM so it would properly charge an AGM battery but that isn't going to happen.
I think this is a non issue but maybe somebody would like to make a comment.
 

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In my 2014 V6 TH I have the an X2Power AGM battery all wrapped up in closed cell foam insulation which is aluminized on both sides.
I DO NOT have an IBS or ESS.
So the battery temperature sensor does not know the temperature of my battery, only the ambient engine compartment temperature.
So will having a different battery type and not knowing the actual temperature of my battery cause a battery charging issue? Or any other issue?
I have been using AGM batteries for about 5 years now and I think battery charging has been just fine.
I understand that flooded and AGM batteries have different charging requirements because my battery charger has a setting for each one.
I was hoping my Jeep dealer could change the software installed in my PCM so it would properly charge an AGM battery but that isn't going to happen.
I think this is a non issue but maybe somebody would like to make a comment.
Sure, I'll comment. You simply aren't getting optimized charging for your AGM. That doesn't mean it won't charge - sure it will. You just won't be getting that supposed 10%-20% life increase that a proper charging profile would be giving.

I put AGM batteries in all my vehicles and only the KL has the fancy charging profiles. Frankly, the AGM batteries in my other vehicles seem to last much longer than the old wet-cell types. They also respond much better to deep discharge. And they all have the old-fashioned take-whatever-the-alternator-gives charging system.

Think of it this way - how much fuel is the ESS saving? Probably very little for most people. I'll bet those that disable ESS see little MPG decrease - but that doesn't mean it isn't saving fuel. Having an optimal AGM charging profile is pretty much in the same boat. It helps - but by how much? Most people probably wouldn't notice.

I believe the point here is IF you have the IBS and ESS, or IF your vehicle demands an AGM, then an optimal charging system probably will help with the life of the battery.
 

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In my 2014 V6 TH I have the an X2Power AGM battery all wrapped up in closed cell foam insulation which is aluminized on both sides.
I DO NOT have an IBS or ESS.
So the battery temperature sensor does not know the temperature of my battery, only the ambient engine compartment temperature.
So will having a different battery type and not knowing the actual temperature of my battery cause a battery charging issue? Or any other issue?
I have been using AGM batteries for about 5 years now and I think battery charging has been just fine.
I understand that flooded and AGM batteries have different charging requirements because my battery charger has a setting for each one.
I was hoping my Jeep dealer could change the software installed in my PCM so it would properly charge an AGM battery but that isn't going to happen.
I think this is a non issue but maybe somebody would like to make a comment.
No worries. AGM batteries have been around much longer than IBS. They are designed to operate and charge with 'regular' battery vehicles.

The difference here is that AGM batteries can accomodate higher Amp charging than flooded batteries, and this advantage is absolutely needed for ESS-equipped vehicles. So in other words, your non-ESS Jeep will benefit from the longer lasting, better cold delivery, somewhat better heat resistance and definitely the many-many more discharge/charge cycles provided by your Northstar (X2 Power) premium AGM, compared to flooded and even lesser lead-calcium AGMs. You won't get those high Amp charging bursts controlled by an IBS, but you don't need them ;)
 
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Think of it this way - how much fuel is the ESS saving? Probably very little for most people. I'll bet those that disable ESS see little MPG increase - but that doesn't mean it isn't saving fuel. Having an optimal AGM charging profile is pretty much in the same boat. It helps - but by how much? Most people probably wouldn't notice.
When it can take 4 light changes to go one block in city traffic, the MPGs really do increase with ESS! Now that my ESS is consistent, my MPGs is up 2+... :cool:
 
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