Jump to content

Ford Professional Technician System (PTS) - "What's New" Item on Battery Load Shed


Haz

Recommended Posts

From PTS...

 

The Workshop Manual, Section 414-01, Description and Operation has been updated on all 2020 and later vehicles with a new folder called Battery Load Shed . 

This folder has information on systems that are affected by battery state of charge during any vehicle system diagnostics.

 

 

414-01 Battery, Mounting and Cables 2020 Edge
Description and Operation Procedure revision date: 07/26/2023

Battery Load Shed

The main purpose of controlling electrical consumption with a load management strategy is to:

  • Limit battery discharge
  • Monitor the battery charge status

 

The alternator is not dimensioned to support all loads in all situations. In some situations energy has to be drawn from the battery. These are mainly during:

  • engine idle
  • cold climate with a lot of electrical heating functions active
  • warm conditions with the engine cooling fan running
  • large transient loads (i.e. EPAS )

 

During cold conditions, the charge acceptance of the battery is very low which increases the time needed to recharge the battery. This means that it can take up to several hours of driving before the battery is recharged.

 

The electrical consumption control is using Ignition_Status, Remote_Start_Status and EngineStateInternal in order to define the load management strategy during the different operating states of the vehicle.

 

The BCM is the primary module that is responsible for controlling the load management strategy. The BCM processes measurements of the system and uses the information for calculations and load prioritization

 

The strategy allows drain to occur from the battery. Load Management minimizes the drain by controlling the time and magnitude of the drain that can occur. The battery drain changes depending on the driving cycle and the types of loads the driver has activated, therefore, the BCM must be able to shut down or reduce the loads if necessary. The intent of the initial load shed stage, LSHED1, is to reduce electrical loads in a manner that is not noticed by the vehicle operator. During LSHED1, requests are sent in a prioritized order for the appropriate modules to begin shedding available loads. In order to prevent customer satisfaction issues, the loads are requested to reduce power consumption with minimum impact to the customer.

 

The second load shed event, LSHED2, occurs in two stages, SHED2_TRANS and SHED2_CONTIN. During operation of a vehicle equipped with large transient loads, there are transient peaks for current draw. The Load Management algorithm reacts to these spikes by using the SHED2_TRANS state. This state requires all non-critical loads to shed immediately, without customer indication, so that large transient loads can operate normally with little to no adverse impact to the customer. SHED2_CONTIN is a continuous deactivation of the loads to ensure the vehicle is able to re-start once the ignition is turned off. During SHED2_CONTIN, a message is displayed to the vehicle operator notifying them of the vehicle's charging system status.

 

Independent of load shed requests, the Load Management control can request boosts to the engine idle speed. Boosting the engine idle speed allows for increased output of the alternator to deliver more current to the battery. Idle speed increases are done through network IBoost messages.

 

The load shed charts provide a general overview of the features available on the vehicle based on the build options.

 

Load Shed Charts

  Priority List Load Shedding 1

 
Priority List Load Shedding 1, Engine Running System Affected Battery State Of Charge (SOC) Battery Voltage
Charging system at 95 % capacity Heated washer fluid Below 62% Below 11.6 Volts
Heated steering wheel
Smart trailer tow battery charge
Heated and cooled seats
Heated back glass, Heated mirrors
Heated wind screen (windshield)
Rear Aux blower
Engine cooling fan
 

  Priority List Load Shedding 2

 
Priority List Load Shedding 2, Engine Running (which includes load shedding 1) System Affected Battery State Of Charge (SOC) Battery Voltage
Charging system at 95 % capacity Energy management relay Below or equal to 50% Below 9 Volts
Non-Chime related information
110 volt inverter
12 volt power points
Ambient lighting
Manual climate control blower (less FMVSS required for operation)

NOTE: The electric booster heater has it's own Load Management strategy which includes idle boost request to the PCM and current limiting capabilities.

Electric booster heater
 

  Priority List Load Shedding Engine Off

 
Priority List Load Shedding Engine Off System Affected Battery State Of Charge (SOC) Battery Voltage

NOTE: Battery SOC threshold may increase slightly as the battery temperature gets colder (i.e. < 0°C /32°F)

  • Ignition on/engine off for > 30 minutes and battery voltage <= to 12.8 Volts (Gasoline engines)
  • Ignition on/engine off for > 30 minutes and battery voltage <= to 13.2 Volts (Electric vehicles)
  • Ignition on/engine off for > 5 minutes and battery voltage <= to 12.8 Volts and battery SOC < 40% (Gasoline engines)
  • Ignition on/engine off for > 5 minutes and battery voltage <= to 13.2 Volts and battery SOC < 40% (Electric vehicles)
Heated washer fluid Loads determined by the engine off timer by the BCM sets the load control status
Heated steering wheel
Smart trailer tow battery charge
Heated and cooled seat (Rear Driver) - stage 3
Heated and cooled seat (Rear Passenger) - stage 3
Heated seat Only (Rear Driver)
Heated seat Only (Rear Passenger)
Heated wind screen (windshield)
Dual automatic climate control front blower (less FMVSS required for operation)
Manual climate control blower (less FMVSS required for operation)

NOTE: Battery SOC threshold may increase slightly as the battery temperature gets colder (i.e. < 0°C /32°F)

  • Ignition on/engine off for > 30 minutes and battery voltage <= to 12.8 Volts (Gasoline engines)
  • Ignition on/engine off for > 30 minutes and battery voltage <= to 13.2 Volts (Electric vehicles)
  • Ignition on/engine off for > 5 minutes and battery voltage <= to 12.8 Volts and battery SOC < 40% (Gasoline engines)
  • Ignition on/engine off for > 5 minutes and battery voltage <= to 13.2 Volts and battery SOC < 40% (Electric vehicles)
Heated back glass, Heated mirrors Loads determined by the engine off timer by the BCM sets the load control status
Split-screen Heated back glass, Heated mirrors
Energy management relay
Infotainment
Electronic Finish Panel (less FMVSS required operation)
110 volt inverter
12 volt power points
Ambient lighting

 

© Copyright 2023, Ford Motor Company.

 


 

 

Document download link> Battery Load Shed - Description and Operation - 2020 & Later Workshop Manuals.pdf

 

 

Edited by Haz
  • Like 2
Link to comment
Share on other sites

I have a 2020 Edge and I have this issue.  I bought a new battery six months ago.  Last week, I received a message on the Sync screen to turn off accessories and all of the keyless entry system except for the driver's door was inoperative.  I charged the battery and the message disappeared from the Sync screen and the keyless entry system again works on all four doors.  I know most of you don't care for the stop/start system, but mine has rarely worked.  I do not drive long distances so that may contribute to my problem.

  • Thanks 1
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...