LR4 "Smart" Charging Charging Strategy

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avslash

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@Daniele Gardellin

Any chance you could tell me exactly what the option you are disabling in the CCF file is called, and where it resides in the CCF menu structure?

Pat from GAP emailed me back and supposedly my IID Bluetooth is now granted access to the complete CCF file, but I don't see anything related to the BMS.
 

Robuk

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You could just disconnect the sensor (small plug) attached to the negative post of the starter battery (as pic), I have been running my Merc for the last 6 months with this sensor disconnected, I have a volt meter attached the the cig lighter socket to check voltage (see pic), it reads between 13.8 and 14.2 volts continuously ( standard charging voltage ), this standard regime also attempts to fully charge the battery not just to 75% as with smart charge, stop/start is also permanently deactivated, to return to normal reconnect sensor plug, Merc has just past it`s MOT with sensor disconnected. No CEL lights on dash, with sensor off line there is no need to register a new battery or use an AGM type as long as battery is not inside vehicle, in that case battery must be spill proof, if sensor is reconnected an AGM must be in place and it must then be registered.

ricksfreeautorepairadvice.com/gm-charging-system-problems/ good read you have to add http : // at front



cig.jpg
Merc neg sensor.jpg
 
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avslash

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I removed the battery sensor today and ran a straight grounding cable.

The truck immediately threw a red fault light for charging system failure from the body control module and the engine control unit module. A shame, because the voltage at idle was a steady 14.00, and I have never read that high at idle.

Hoping Patrick can get me hooked up with the ability to disable the BMS via the IIDTool. I am corresponding with him now.

Just thought I would let you guys know what was going on.
 

Robuk

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I removed the battery sensor today and ran a straight grounding cable.

The truck immediately threw a red fault light for charging system failure from the body control module and the engine control unit module. A shame, because the voltage at idle was a steady 14.00, and I have never read that high at idle.

Just disconnect the sensor and do nothing else, you should get NO EMl`s, where did you run the grounding cable from, that is obviously causing your charging system failure fault light, I have no problems with this disconnect on my C Class and SLK Mercs.
 

avslash

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Thanks Robuk for a timely bump to this thread. I just sat down to offer an update, as well.

I had replaced the starting battery ground strap with the BMS sensor with a straight ground strap. It almost immediately triggered a fault in the BCM (Body Control Module) and the ECM (Engine Control Module). I replaced the straight ground strap with the factory version, and the faults cleared.

However, I have another update to offer.

I had a PC issue which was preventing me from getting the "unlocked" version of the CCF file in the IIDTool. I got that sorted out with Patrick today, and now have the unlocked version on my IIDtool.

There is a setting under the "untested" menu to configure the vehicle without a BMS sensor. I uploaded the CCF into the vehicle with that modification, and the results are very promising.

After starting the truck with the modified CCF file loaded, and the factory ground strap with BMS sensor in place, I immediately noticed a voltage reading of 14.7. This is the highest voltage reading I have ever seen on the truck.

In a bit of driving around with the updated CCF, I never saw the voltage decline below 14.5 volts. This contrasts with my previous experience of seeing the voltage fluctuate anywhere from 14.5 at startup to as low as 12.7 while driving around, with about 13.7 volts being the average voltage I would see.

In the current configuration with the modified CCF and the factory ground strap with sensor, I am not getting any faults.

If I have time tomorrow, I plan to swap the factory ground strap with sensor out for a straight ground strap again and verify that there are no faults in that configuration.

Using the "Live Values" feature on the IIDTool, the highest "state of charge" I was typically able to get was 79%. I will monitor this over a few days and see if this mod allows that to creep somewhat higher.

Very happy with this development, and will update you guys after a bit of time with it. I have roughly $650.00 worth of batteries under the hood, and it ****** me off to no end to not be able to charge them to capacity due to some nanny function of the truck. Hopefully this did the trick. I can't say for sure yet, but the data looks promising at this point.
 

djkaosone

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@avslash Did you ever get the straight ground cable in? I emailed Pat at GAP IIDTool and he enabled my IIDTool, but I haven't quite got a chance to get to it. It's been raining in San Diego and I didn't want to mess with the electrical.

Any tips on how to get the IIDTool to see the new "untested" menu? PM me. Thanks in advance.
 
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TheWidup

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Forgive the ignorance here...but is this the reason for the dip in the headlights at night? Seems like they dim and come back a fair amount and wondering if it's charging related.
 

gsxr

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Forgive the ignorance here...but is this the reason for the dip in the headlights at night? Seems like they dim and come back a fair amount and wondering if it's charging related.
I've noticed the same thing and was also wondering how Land Rover could do anything like this on purpose. Makes me wonder if the lights are not supposed to dim visibly, and the intermittent dimming may indicate something is wrong / failing?

o_O
 

rally3

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The known issue of headlight dimming has been with non hid lights and it is when the heated windshield is automatically turning on and off, Land Rover changed the programming on later models to combat this,
the voltage fluctuation from the adaptive charging is not a sudden change, so it should not be noticeable
 

Robuk

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avslash,

That`s brilliant, Ford used to do a smart charge deactivation but it appears this is no longer allowed, the only way to get rid of smart charging in the Merc`s is the sensor disconnect, 8 months now and NO issues.
With the disconnect on Merc`s it also gets rid of stop/start which for me was the sole object of the exercise, deactivating the smart charge was a bonus. I assume your recoding also gets rid of the stop/start function. I have read that an AGM battery needs a float charge of around 13.8 which my Merc`s have, I would check that your higher 14.5 voltage does not overcharge the battery, perhaps this higher voltage will drop once the battery is fully charged.

My thinking on the disconnect is that it is seen by the EMU as a failed sensor, whereby the EMU would put the alternator into a pre-configured charging sequence for whatever battery was fitted before disconnect. Could you post voltage reading after a week or so with your recode.

Regards, Rob
 
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