Jump to content

Battery monoriting reset


Recommended Posts

Specific to your question about how to accomplish a Battery Monitoring System (BMS) reset without use of a scan tool, I have edited a portion of the 2013 Edge-MKX Workshop Manual to provide you the answer...

 

If the reset is not carried out [using a scan tool] it takes approximately 8 hours for the BCM to learn the new battery state of charge. During this 8 hour period, the vehicle must be undisturbed, with no doors opened or keyless entry button presses. If the vehicle is used before the BCM is allowed to learn the new battery state of charge, engine off load shedding can still occur and a message may be displayed.

 

The full Workshop Manual section from which this brief passage, which describes the entire Battery Management System and the proper connection of an external battery charger, can be downloaded using the following link...

 

Charging System - Principles of Operation - 2013 Edge-MKX Workshop Manual.pdf

 

While not mentioned in the document, it would not hurt to begin the 8 hour undisturbed period by fully locking the vehicle, which most promptly allows the vehicle's electronic modules to power down into their 'sleep' state.

 

Good luck!

 

  • Like 1
Link to comment
Share on other sites

Haz,

Thank you very much. I'll do the 8 hour undisturbed, see what happens.  I installed the new battery and started using car, not thinking or knowing about reset. Low battery message has only come on twice in the 6 month since new battery was installed. Get message when startinng.

Thanks again

Larry

Edited by Larry
Link to comment
Share on other sites

Haz using this method I assume does not reset the battery "days in service".  I have used Forscan Lite to reset the Battery Minder when a new battery was installed and it reset the days in-service to zero.  

 

A paragraph in a 2019 service manual says that it is important to reset, when a new battery is installed, so all of the charging algorithms know it is a new battery and not one that has been in-service.

 

Are these two different types of resets ?

Link to comment
Share on other sites

To reset the battery monitor on any Ford product:

 

1. Make sure all windows & doors are closed.
2. Turn ignition switch to on (don't start car). Wait 10 seconds.
3. Flash highbeams 5 times using the "flash to pass" stalk on the side of the steering wheel (on/off, on/off, on/off, on/off, on/off).
4. Press brake pedal 3 times in 10  seconds.
5. The battery light on instrument cluster will flash indicating the BMS has been reset.

Edited by enigma-2
  • Like 1
Link to comment
Share on other sites

11 hours ago, enigma-2 said:

To reset the battery monitor on any Ford product:

 

1. Make sure all windows & doors are closed.
2. Turn ignition switch to on (don't start car). Wait 10 seconds.
3. Flash highbeams 5 times using the "flash to pass" stalk on the side of the steering wheel (on/off, on/off, on/off, on/off, on/off).
4. Press brake pedal 3 times in 10  seconds.
5. The battery light on instrument cluster will flash indicating the BMS has been reset.


Where did you find this?  Have you actually done it?

Link to comment
Share on other sites

That is a great question, JoeVic!

 

The existence, usage, and effects of a Battery Monitoring System (BMS) Reset varies across the generations of Edge/MKX/Nautilus vehicles, according to my survey of relevant sections in each generation of Workshop Manuals.

 

Gen 2 vehicles' (2015-2023 Edge, 2016-2018 MKX, 2019-2023 Nautilus) Electrical Management System employs the most sophisticated and most effective charging and electrical circuit load shedding strategies, based upon algorithms in the Body Control Module (BCM) software, battery age calculations from a time-in-service counter, and battery state-of-charge judgements from up to 8-hours of battery voltage history stored in the BCM, as measured by the Battery Monitoring Sensor mounted on the negative battery terminal clamp.

 

Performing a BMS Reset on a Gen 2 vehicle is reserved for new battery installation only, per the Workshop Manual, which infers the BMS Reset establishes a new battery time-in-service counter start point, and erases the battery voltage history, which creates a new baseline of data for the algorithms in the BCM software to apply toward Electrical Management System charging and load shedding outcomes.

 

This limited use of a BMS Reset in Gen 2 vehicles provides only one method for dealing with invalid battery voltage data created when jump starting or externally charging the battery with the device's negative lead improperly attached to the negative battery post, which disrupts the Battery Monitoring Sensor's measurements. In this case, a valid span of historical values must be recreated by the leaving the vehicle undisturbed in sleep mode for a period of 8 hours, with no current draws above 300mA. The attainment of sleep mode occurs more promptly by locking the vehicle with all doors, hood, and liftgate closed, and with no subsequent presses of remote key/fob buttons.

 

If the 8 hour undisturbed vehicle corrective method is not applied after faulty data is recorded in the BCM, then Gen 2 load shedding events may occur sooner than actually needed until calibration is otherwise fulfilled.

 

It's worth noting that properly connecting the jump starter or external battery charger negative lead onto a body ground-point (shock tower sheet metal bolt head) avoids the faulty data creation and eliminates the need for 8 hours of undisturbed vehicle sleep mode, with normal state-of-charge calibration occurring during 4-6 hour periods of everyday vehicle downtime in sleep mode.

 

Gen 1+ vehicles' (2011-2014 Edge, 2011-2015 MKX) Battery Management System lacks Gen 2's BCM algorithms and battery age monitoring, but it still achieves enhanced charging and load shedding performance using the same up to 8-hours of battery voltage history stored in the BCM, as measured by the Battery Current Sensor mounted on the negative battery terminal clamp.

 

In Gen 1+ vehicle Workshop Manuals, surprisingly, no mention is made about performing a BMS Reset when a new battery is installed.  BMS Reset is to be employed when instances of faulty or an absence of battery voltage data history occurs in the BCM.

 

In Gen 1+ vehicles, to avoid the need for a BMS Reset, jump starting and external battery chargers negative lead should be connected to and engine or body ground point the key/ignition status should be 'ON', which allows the BCM to record battery voltage values when the external device is in use. If the key/ignition status is 'OFF' or the device's negative lead is attached to the negative battery post, then the BMS Reset must be performed, or as an alternative, leaving the vehicle undisturbed in sleep mode for a period of 8 hours. The attainment of sleep mode occurs more promptly by locking the vehicle with all doors, hood, and liftgate closed, and with no subsequent presses of remote key/fob buttons.

 

If a BMS Reset or the 8 hour undisturbed vehicle method is not applied after faulty data is recorded in the BCM, then Gen 1+ load shedding events may occur sooner than actually needed.

 

Gen 1 vehicles' (2007-2010 Edge/MKX) Powertrain Control Module (PCM) simultaneously monitors and controls the charging system and battery voltage, without any battery age awareness or battery state-of-charge-based load shedding capability. Lacking these, no BMS Reset procedure exists for Gen 1 vehicles.

 

Good luck!

 

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...