Super slow charge on NEMA14-50 on a 50 AMP circuit and using Ford Mobile Charger

[SLTX]

Am I losing my mind here or am I doing something wrong.

Plugged the mobile charger in today after driving around. Charge start at 90% and came home at 45%. Plug the truck up and looked on the Ford app. It showing charging ranging from 1.4 to 3.2. It peaked earlier at 4.7 kW. Thought it would do 7.2 or something in that neighborhood. Says it'll finish charging to 80% on Tuesday (tomorrow) at 8:38AM. Can't be serious. I checked the breaker and it's on a 50 AMP circuit. Sure it's a bit warm here (85 but feels like 91) but that can't be why it's charging so slow on 240/50, can it?

Did I do something wrong here?

TIA!

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[K6CCC]

Sounds like you are doing it right. A couple things to test (depending on what test capabilities you have). If you have a voltmeter, make sure that the 14-50 outlet really is sourcing 240 volts. It should be 115-120 from each hot terminal to the neutral, and 230-240 between the two hot terminals. Yea, those voltages could be a little out of the range I listed.
Second is if you have an OBD2 device and CarScanner, connect and see what it shows for the power source. It should show the voltage under load (once you get to the right screen).

 

[SLTX]

Sounds like you are doing it right. A couple things to test (depending on what test capabilities you have). If you have a voltmeter, make sure that the 14-50 outlet really is sourcing 240 volts. It should be 115-120 from each hot terminal to the neutral, and 230-240 between the two hot terminals. Yea, those voltages could be a little out of the range I listed.
Second is if you have an OBD2 device and CarScanner, connect and see what it shows for the power source. It should show the voltage under load (once you get to the right screen).

Yeah, going to have to go to University of Youtube to test the receptacle with a 2003 Radio Shack voltmeter.... go me.

You think it's safe to use my brother's Volvo's OEM charging cable to see if it might be the mobile charger?
I don't have carscanner (will Blue Driver work?). I do have the ODB-usb dongle (arrived yesterday.... wife is going crazy with all the Amazon packages for the truck and none for her... oops!). Is there an PC app I can use to check?

Thanks for the fast reply!!

 

[hturnerfamily]

if it's working, then the 240v output is also working, as the Mobile EVSE will not work without 240v power...so, if you are only able to refer to your APP, then while it's likely correct, the Mobile EVSE is also likely vacillating the power output to the truck, for some reason: many of us have seen the unit do this, and yes, it 'could' be heat related, but for most of us with issues with the unit, it's likely a faulty built-in sensor, derating the output to the truck.

Try another EVSE to see ... that's about all you can really do.

The 50amp breaker set would also not be faulty, although the NEMA 14-50 outlet could be suspect.
I would just try another EVSE first...

While I don't use the good ol' Ford Mobile EVSE anymore for 'everyday' charging, as it, too, started derating every session, I still have it with me 'just in case'... well,... what else is it good for?
Yes, it works, but when it slows to 3.2kw, versus the expected 6.4kw, it's a little concerning... the unit has little to no information about the output, either, like many others do...so, you can only guess.

 

[K6CCC]

if it's working, then the 240v output is also working, as the Mobile EVSE will not work without 240v power...

Nope. Works fine on 120V (albeit slowly). If you have the 14-50 adapter plug on the MCC, but the 14-50 outlet is hot on only one wire, the result will be pretty close to what the OP is seeing - hence my suggestion to measure it.

 

[SLTX]

if it's working, then the 240v output is also working, as the Mobile EVSE will not work without 240v power...so, if you are only able to refer to your APP, then while it's likely correct, the Mobile EVSE is also likely vacillating the power output to the truck, for some reason: many of us have seen the unit do this, and yes, it 'could' be heat related, but for most of us with issues with the unit, it's likely a faulty built-in sensor, derating the output to the truck.

Try another EVSE to see ... that's about all you can really do.

The 50amp breaker set would also not be faulty, although the NEMA 14-50 outlet could be suspect.
I would just try another EVSE first...

While I don't use the good ol' Ford Mobile EVSE anymore for 'everyday' charging, as it, too, started derating every session, I still have it with me 'just in case'... well,... what else is it good for?
Yes, it works, but when it slows to 3.2kw, versus the expected 6.4kw, it's a little concerning... the unit has little to no information about the output, either, like many others do...so, you can only guess.

I went outside and unplugged the charger and plugged it back in (the good ol' "Have you tried to turn it off and on" debugging tool). Now it shows what you mentioned. It's at 3kW bouncing between that and 5.9. The sun is setting here in Houston area and it's getting cooler so I'll monitor it in relation to the temp. After dinner, I'm going to raid my brother's charger and test it out.

Thank you!

 

[TaxmanHog]

The Ford Mobile Charger aka FMC suck, yours might be on its last leg, try the Volvo charger

 

[Maquis]

What color lights are showing on the FMC? Amber means it’s being derated due to temp. See the owners manual for a complete matrix of light combinations.

 

[SLTX]

Sorry, watching the playoffs.

The charger is blue.

I'll be trying the Volvo charger tomorrow. Too many Texas state bird (mosquitoes) out right now.

 

[Lucky Larry]

the mobile charger will do a maximum of 7.2 kw and pull 32 amps on a 240 volt circuit. the first place to start would be with the volt meter checking the voltage on the 2 hot lines as mentioned by
@K6CCC . if you don't have 240 volts next check for 120 volts on each hot line. if you only have 120 volts on 1 of the 2 hot lines, you may have a loose or broken wire on the hot line with no voltage on the receptacle. next flip your circuit breaker off and investigate the connections on the back of 14-50R receptacle for loose or broken wires.

 

[TaxmanHog]

Unseat and firmly plug in the 240v dongle into the FMC.

 

[Mal106]

Im sure you checked the obvious that the current limit isn't set in the APp.

 

[TaxmanHog]

Im sure you checked the obvious that the current limit isn't set in the APp.

Is that a feature in 2023 Lightnings?
I thought it was only on 2025 trucks!!


If he were using a FCSP then I'd agree the FCSP charging rate could be reduced, but he's using a nonadjustable FMC.

 

[Mal106]

I'm slowly finding the 25 to be a different beast.

 

[chl]

The FMPC has had a lot of heat related issues and failures, and is not the best idea for regular daily use, sometimes it is the 240v dongle does not seat well or has corrosion on the contacts that leads to electrical resistance and heat.

Get a good wall mounted hard-wired EVSE and put the FMPC in your Frunk for emergencies, as others have recommended.

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