Monitor and/or control EV battery preconditioning

[mattxcnm]

Description

It would be great to be able to see when my EV is in battery preconditioning mode. The Ford website says this occurs when your navigation is set to a DC fast charger and I can see the battery temperature raising rapidly with this integration.

https://www.ford.com/support/how-tos/electric-vehicles/charging-management/preconditioning-overview/

https://www.ford.com/support/how-tos/electric-vehicles/public-charging/how-do-i-precondition-my-mustang-mach-e-battery-for-dc-fast-charging/

I would like to be able to see an entity that shows the preconditioning being active and better yet have the ability to turn it on myself as I do not plan on keeping the navigation subscription therefore I lose the ability to precondition.

If needed I can provide more data and logs to assist in this. I have a 2024 Mustang Mach-E extended eAWD.

AMAZING work on this integration!! Thank you so much for your time and effort.
TIA

JSON Object/Key

[marq24]

Hi Matt,

thanks for sharing this very interesting info - as owner of a Mach-E extended range I am quite surprised, that the linked Ford documentation indeed indicates, that Mach-E have battery preconditioning feature.

You just wrote

... and I can see the battery temperature raising rapidly with this integration

So you see that "something" is happening... I have to admit, that I haven't used any DC charger yet (but that's a different story) - so I can't deny (or confirm) that a 'battery preconditioning' might exist.

But I am really wondering how this is implemented @ Ford... What is very suspicious for me is, that (based on the provided docs) this only works while activity navigate with GoogleMaps (via AndroidCar). To be honest this limitation, does not make any sense for me. I would understand, if this would only work, when navigating with the Ford build in OnBoard navigation - but why this depends from Google services?! From a commercial angle: why I (as car manufacturer) should make my car-feature dependent from 3'rd party ?

But let's put this aside for a moment - let's "speculate" how this is currently working:

at home

Based on the documentation, as soon as the car is connected to your Wallbox, the system somehow decide if preconditioning becomes active - I haven't evaluated this deeper - but I expect, that in the EVData Sensor Attributes you might be able to finde an indicator?

while on road (@ navigating with Google)

When you are approaching the DC Station (again why it's required google services to know the car location/distance to DC station)... someone decided to activate 'battery preconditioning'...

Here is question is, who is this someone?

The Car

If this switch is triggered by the local onboard unit running on the car, then I do not see a way to trigger this from remote. If it#s really the car, then IMHO any external dependencies would be totally stupid [so the in place restrictions mentioned in the docs makes no sense - which makes it quite possible, that it's not the car]

A backend System

If a backend system makes the decision, then there "must" be a ON/OFF communication from/to car with a backend system. IF there is an option/way to sneak into this communication [aka man in the middle] it totally unknown

my conclution

As long as there is no button inside the car and/or a button in the FordPass App, I do not see a way to be able to have any kind of influence.

Have that said, there might be 'metric' data received by FordPass App (and now by the Integration) that at least would allow the have a Status Sensor - therefore we must monitor changes in the ALL the metrics... (and know at least a time frame in which we should analyse the data)... You know, that there is a "debug" all-metrics Sensor already available ?

[mattxcnm]

Battery temperature observed while "preconditioning"

On my last road trip, I did some experiments to see what happens when "preconditioning", following the steps given in that link above (I do not have AndroidAuto). I used the Ford OnBoard navigation and noticed that about 15-20 minutes before arriving at the DC fast charger the battery temperature would spike. I made sure this integration was running so I could collect data. Here is what I noticed:

A - Navigation started to DC-fast charger
B - Actually starting the DC fast charging (charger was broken so I had to move to a different one, which allowed the battery to cool)
C - Navigation started to DC-fast charger
D - DC fast charging started.

Charging each time took less than 30 minutes and the battery seemed to cool slightly after actually starting the charger but I only got 1 or 2 updates from the car while charging. Other than the 2 charging stops, driving was constant the whole time on this graph after point "A".

Debug metrics

I am also skeptical that a method of manually enabling this is unlikely, but having the data would be nice as I plan to analyze the car's metrics over its lifetime so the more data the better.

I believe I have the ""debug" all-metrics Sensor" enabled, is it "sensor.fordpass_[vin]_metrics"?

What is the best way to compare changes in the Metrics? Does Home Assistant save historical Attributes with Recorder?

I was thinking of using VS Code and comparing the entire Attributes portion of the Metrics sensor before and during "preconditioning".

[crowedavid]

HV battery preconditioning is not currently a function that can be enabled by the end user directly; there is no toggle for it in the car console, there is no toggle for it in fordpass. as noted in the links provided in the original comment for this issue there are only a few ways to trigger it currently:

• use "departure times" and have your car plugged in when they trigger
• navigate directly to a DC charger using in car systems (probably using android auto too but i haven't verified myself)
• navigate on a trip using either in car navigation system or android auto and let the navigation system add DC chargers

they also have some conditions that need to be met before the car will turn it on to make sure the precondition activity doesn't inhibit your ability to make it to the charger with some buffer remaining (5% SoC/10 miles estimated range).

many folks on the mach-e and lightning forums (probably elsewhere) have been asking ford for a "precondition now" button but silence appears to be the only answer so far. android auto and ford enabled the ability to trigger it last fall; i expect carplay will have the ability at some point. i'm quite a bit annoyed at the statement that a "Connected Navigation Subscription" is also required but i have a year left before that runs out before needing to decide or see if the requirement is actually in play.

now that we have a continuous stream of data with websockets (such a huge improvement!) you can intuit from the batteryTemperature data if your car is actually preconditioning prior to charging but that's about it.

@mattxcnm asked:

What is the best way to compare changes in the Metrics? Does Home Assistant save historical Attributes with Recorder?

the HA database doesn't save attribute data over time. you'll need to create a template sensor for the attribute(s) and then you can look at longer time history for comparisons. it looks like you've already done this for the battery temperature so you should be all set. if you also template the chargingVoltage and/or chargingAmperage you can line up when the actual charging sessions happen and see if the preconditioning is happening or not. note that those values also appear during regeneration so you may also want to watch chargingType. that's my current plan.

[marq24]

so with https://github.com/marq24/ha-fordpass/releases/tag/2025.6.18 you have the option to save all data read from the backend systems to the local file system of your HA instance - so next time you are approaching a DC station (on a planed trip) you might find some property in the data - I'll keep my fingers crossed.

[crowedavid]

data dump surprise find: ford uses SMS messaging to request the car to wake up and update ( press button.fordpass_VIN_remote_refresh ). that's one way to keep idle power usage very low. :-)