2025 Hybrid - Potential Battery Drain?

[johnDeere]

Did you have the update performed on the ACCM (air compressor control module) . That has eliminated the excessive drain on MOST vehicles. I recommend it

Hello Darryl,
I have not had the ACCM updated yet.
As for my 23 mav hybrid, my current drain can last sometimes up to 2 hours before my 'volt amp" meter shows .00.
I am normally up to 90%+ SOC, and can loose up to 5% over night, but can replenish it back to 90% by driving to work.
I would not say, I have the parasitic drain, that will drain the battery dead.
I have the 12v drain where things take time before they shut off completely.
I have one of these installed on my truck. (volt amp meter)
I also have "Car scanner" app installed on my truck, so I can see whats going on on my truck screen.

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[zen_]

Unless a person has had the SSM that says to update the ACCM, they haven't done what is necessary to solve the problem. If that doesn't work, it's one thing. But if that has not been tried, try it before condemning the Maverick. It actually gets rid of the parasitic drain for most vehicles.

My post was mostly just wondering why an AC control module is connected to the 12v system, which is interesting since apparently some Toyota / Lexus hybrids are configured the same way with the 12v battery powering up that same (?) module.

 

[HeyBales]

My post was mostly just wondering why an AC control module is connected to the 12v system, which is interesting since apparently some Toyota / Lexus hybrids are configured the same way with the 12v battery powering up that same (?) module.

All the modules use 12V, if key not to On state - it's running off the battery, if On or Started - then DCDC Converter from ICE/Regen/HVB.

Of course it requests compressor on/off/speed from the 3-Phase system.
It also has ability to request cooling fans and report to other modules - if it goes haywire it could be requesting actions when other modules have gone to sleep, so it keeps it's draw up. If it can communicate it could request unneeded actions that get stuck. Couple posters reported their fans running hours after truck shut-off. Was ECM left running to control that action?
Seems the whole system has claims in the service manual of disabling systems that shouldn't be drawing power - doesn't seem to work correctly.

 

[zen_]

All the modules use 12V, if key not to On state - it's running off the battery, if On or Started - then DCDC Convertor from ICE/Regen/HVB.

I must have falsely been under the impression for years that the 12v accessories were mostly powered by the stepped down current from the HV traction battery (used to charge the 12v battery). I had to take an Uber to the Toyota dealership to get a 12v battery for my Prius when it wouldn't turn turn on in a parking garage, and from what I gathered at the time, that was SOP because you just don't know it's dead until the voltage is too low to turn on the module that turns the HV relays on (ignition on).

 

[johnDeere]

I must have falsely been under the impression for years that the 12v accessories were mostly powered by the stepped down current from the HV traction battery (used to charge the 12v battery). I had to take an Uber to the Toyota dealership to get a 12v battery for my Prius when it wouldn't turn turn on in a parking garage, and from what I gathered at the time, that was SOP because you just don't know it's dead until the voltage is too low to turn on the module that turns the HV relays on (ignition on).

I had a 2006 toyota highlander hybrid that when the battery was low, the computers would not start up period. you had to use a jump box to get the computers to start.
Back then no sleep mode.

 

[HeyBales]

I must have falsely been under the impression for years that the 12v accessories were mostly powered by the stepped down current from the HV traction battery (used to charge the 12v battery). I had to take an Uber to the Toyota dealership to get a 12v battery for my Prius when it wouldn't turn turn on in a parking garage, and from what I gathered at the time, that was SOP because you just don't know it's dead until the voltage is too low to turn on the module that turns the HV relays on (ignition on).

I didn't say 12V battery, 12V system.

The HVB is not left connected to all the wires it uses when the vehicle is off.
For safety - off should be off, at least under the hood I guess.

When the 12VB power throws the relay to allow that power thru - now you got the DCDC supplying the 12V system.
That happens for the Mav when key goes to On, or keyless to Accessory mode.
I recall despite manual calling it Accessory mode, drivers reported it's actually closer to On, with the HVB connected. Or I'm mis-remembering, because manual sure seems to make it sound like Acc mode only.

Switching the Ignition to Accessory Mode
When the ignition is off, press the push button ignition switch once without your foot on the brake pedal.
All electrical circuits and accessories are operational and the warning lamps and indicators illuminate.
Note: Your vehicle has a battery saver feature that shuts your vehicle off when it detects a certain amount of battery drain, or after approximately 30 minutes of inactivity in accessory mode.

 

[Packer Bill]

I also have "Car scanner" app installed on my truck, so I can see whats going on on my truck screen.

How did you install the car scanner app on your truck screen? Are you using Android Auto?

 

[johnDeere]

How did you install the car scanner app on your truck screen? Are you using Android Auto?

I am using a ODB2 to Bluetooth unit and car scanner app on my Iphone with car play.

 

[Packer Bill]

I am using a ODB2 to Bluetooth unit and car scanner app on my Iphone with car play.

Thanks for responding so quickly.

I am using Android Auto. I finally was able to get Car Scanner show as being available in Android Auto. I am thinking that an update to Car Scanner app at the end December made it compatible with Android Auto. I will check this tonight when I drive my Maverick to a meeting.

 

[MakinDoForNow]

I didn't say 12V battery, 12V system.

The HVB is not left connected to all the wires it uses when the vehicle is off.
For safety - off should be off, at least under the hood I guess.

When the 12VB power throws the relay to allow that power thru - now you got the DCDC supplying the 12V system.
That happens for the Mav when key goes to On, or keyless to Accessory mode.
I recall despite manual calling it Accessory mode, drivers reported it's actually closer to On, with the HVB connected. Or I'm mis-remembering, because manual sure seems to make it sound like Acc mode only.

Switching the Ignition to Accessory Mode
When the ignition is off, press the push button ignition switch once without your foot on the brake pedal.
All electrical circuits and accessories are operational and the warning lamps and indicators illuminate.
Note: Your vehicle has a battery saver feature that shuts your vehicle off when it detects a certain amount of battery drain, or after approximately 30 minutes of inactivity in accessory mode.

Note: if you push the button without foot on brake within (10?) seconds of pushing it to turn ready state off without opening the door the truck is returned to ready state without verifying key is in vehicle. Pushing button once after 10 seconds then turning something on or plugging into power points you should get pop up showing extended accessory mode is active. (If I remember correctly).

 

[Darryl]

My post was mostly just wondering why an AC control module is connected to the 12v system, which is interesting since apparently some Toyota / Lexus hybrids are configured the same way with the 12v battery powering up that same (?) module.

The control side of the ACCM is 12 volts. The actual compressor runs off of the high voltage battery. That's true for every module that interacts with the high voltage system. By the way. The air conditioner control module is integrated into the compressor. At this particular time. You can't service them separately

 

[KenE]

So far so good! My issues didn't start till after truck was two years old.

My Mav is nine months old so 15 more months of grace period Lol !

 

[KenE]

Thanks for responding so quickly.

I am using Android Auto. I finally was able to get Car Scanner show as being available in Android Auto. I am thinking that an update to Car Scanner app at the end December made it compatible with Android Auto. I will check this tonight when I drive my Maverick to a meeting.

I use Car Scanner via Android Auto. Works fine but I'm not able to get more than four (4) lines of data on the screen. Others shiw eight (8) lines of data. I assume it's a font setting somewhere OR they are using Apple Car Play, meaning 4 lines of data is an Android Auto limitation?? I'd sure like to get 6 or 8 lines if data to see at once.

 

[Neils Bohr]

My Mav is nine months old so 15 more months of grace period Lol !

Lol! Good news is mine is fixed for now.

 

[KenE]

Lol! Good news is mine is fixed for now.

Keep fingers crossed. Our Mavericks are like a mystery movie - always guessing, who's the villain? Is there a happy ending, or even an ending. Ha!

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