12v Solar Charger Work?

[Zak Attack]

On our previous ICE vehicle, when we were out of the country for 4 or 5 weeks, we had a small 5w solar panel that sat on the dash and plugged into a power(lighter) outlet. This would act as a trickle charger and keep the 12v battery topped up.
Does anyone know if this would work on a (2025) MME?

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[SpaceEVDriver]

It would work just fine, but it’s entirely unnecessary.

 

[Maquis]

It would work just fine, but it’s entirely unnecessary.

I thought the 12V outlets shut off after several minutes?

 

[SpaceEVDriver]

I thought the 12V outlets shut off after several minutes?

I think you're right.
So that method wouldn't work and it's not necessary to have any supplemental 12v power.

 

[tbrumleve]

The HVB will keep the 12v charged as needed. If you’re talking a trickle charge for the HVB, there are solar solutions that’ll add a couple / few miles a day.

 

[Zak Attack]

It would work just fine, but it’s entirely unnecessary.

It would work just fine, but it’s entirely unnecessary.

On our previous ICE vehicle, when we were out of the country for 4 or 5 weeks, we had a small 5w solar panel that sat on the dash and plugged into a power(lighter) outlet. This would act as a trickle charger and keep the 12v battery topped up.
Does anyone know if this would work on a (2025) MME?

Just to be clear here, we would be parking our vehicle at an airport parking lot for 4-5 weeks and it would only have remaining 60% charge when leave it. So the only charging that would be happening (if it even works) would be the 5w solar solar panel left on the dash through the power/lighter outlet.

 

[SpaceEVDriver]

Just to be clear here, we would be parking our vehicle at an airport parking lot for 4-5 weeks and it would only have remaining 60% charge when leave it. So the only charging that would be happening (if it even works) would be the 5w solar solar panel left on the dash through the power/lighter outlet.

The manual says the following for a 30+ day storage, including a suggestion to disconnect the 12V battery.

But if I'm going to store the vehicle at the airport, I don't bother disconnecting the 12V battery. In part because I would need to bring an extra 12V battery to open the frunk when I want to reconnect the car’s 12V battery. Or I would need to leave the frunk open. Neither is a realistic option.

So, I leave it at whatever charge it has when I get to the airport, shut it off, and don’t use my phone to check on it while I'm away. Every time the phone is used to check on the vehicle, it causes the vehicle to wake up and use some of that 12V battery. Unless you run a connection from the 12V battery under the frunk to your solar panel, you won’t be able to trickle charge it.

 

[Maquis]

Just to be clear here, we would be parking our vehicle at an airport parking lot for 4-5 weeks and it would only have remaining 60% charge when leave it.

Park it and forget about it. It will be fine.

 

[HuntingPudel]

You likely will not have a problem unless your LVB is in a bad State of Health. In that case, a trickle charging solar panel won’t help. That said, if you are concerned about LVB discharge, you could hard wire a cigarette lighter socket to an unswitched fuse and ground, then plug your panel’s charging unit into that.

 

[Zak Attack]

The manual says the following for a 30+ day storage, including a suggestion to disconnect the 12V battery.

But if I'm going to store the vehicle at the airport, I don't bother disconnecting the 12V battery. In part because I would need to bring an extra 12V battery to open the frunk when I want to reconnect the car’s 12V battery. Or I would need to leave the frunk open. Neither is a realistic option.

So, I leave it at whatever charge it has when I get to the airport, shut it off, and don’t use my phone to check on it while I'm away. Every time the phone is used to check on the vehicle, it causes the vehicle to wake up and use some of that 12V battery. Unless you run a connection from the 12V battery under the frunk to your solar panel, you won’t be able to trickle charge it.

Thanks (for the best reply)

 

[AzYooper]

We left our Mach-E sitting in the garage with an 85% charge for five weeks, or 35 days while vacationing. We did this for two years in a row, so far. It "goes to sleep" and does not wake up until we return. We got back it and it has not been below 80%. We don't activate Ford Pass to check battery levels during our absence since this would "wake it up."

 

[doogie63]

I'm at the Ford dealership right now getting oil changed in my other car. I notice on their Mach-E they have a small solar panel in dash. They said they do it to trinkle charge it to keep charged. Didn't look like it was plugged into cigarette lighter. Look more like it was plugged in the OBDII. Took pictures but when I try to upload picture is all messed up.

 

[doogie63]

 

[HuntingPudel]

I'm at the Ford dealership right now getting oil changed in my other car. I notice on their Mach-E they have a small solar panel in dash. They said they do it to trinkle charge it to keep charged. Didn't look like it was plugged into cigarette lighter. Look more like it was plugged in the OBDII. Took pictures but when I try to upload picture is all messed up.

This would work fine for a panel with a relatively low power output. Something under 10W at 13V should be fine. Pin 16 is Batt+ and 4 is chassis gnd.

 

[Maui]

Hmmm… could be useful for airport parking etc.

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