Power Port Repeatedly Loses Power Every 10 seconds

[LIVETOLEARN]

My power station gets power from the 12V rear power port. Lately, it has stopped charging from the port. With multiple cables the port starts to put out 12v and cuts power within a second to 0v for ten seconds and this repeats. I've check this with just a multimeter and same result. The same result happens with the front 12v power port in the center console.

Any suggestions what to look for?

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[Brian_B]

The universal first thing to do when weird stuff starts happening:

Pull negative lead for about 5 minutes and reconnect. Put your battery on a charger over night. See if it continues after that.

That will reboot everything in the Bronco and ensure the battery is topped off.

 

[LIVETOLEARN]

The universal first thing to do when weird stuff starts happening:

Pull negative lead. Put your battery on a charger over night. See if it continues after that.

That will reboot everything in the Bronco and ensure the battery is topped off.

I'll do that tonight. Thank you.

 

[Brian_B]

I'll do that tonight. Thank you.

I should say I ninja edited the post:

Pull the lead for about 5 minutes then reconnect. When you connect the battery to the charger - make sure to use chassis ground or the side of the terminal, not the actual terminal post for the negative

Reason being the BMS system needs to see the charge going into the battery, and the BMS is that little thing sticking out the side of the negative battery terminal. That needs to be in the circuit for the system to see the charge. If you go straight to the negative post it bypasses the sensor and the BMS doesn’t see the charge going in (it doesn’t just react to voltage alone)

Positive can go right to the terminal post though.

 

[LIVETOLEARN]

I

I should say I ninja edited the post:

Pull the lead for about 5 minutes then reconnect. When you connect the battery to the charger - make sure to use chassis ground or the side of the terminal, not the actual terminal post for the negative

Reason being the BMS system needs to see the charge going into the battery, and the BMS is that little thing sticking out the side of the negative battery terminal. That needs to be in the circuit for the system to see the charge. If you go straight to the negative post it bypasses the sensor and the BMS doesn’t see the charge going in (it doesn’t just react to voltage alone)

Positive can go right to the terminal post though.

I am not using a charger for the power station but connecting the power from the 12v cigarette port to the input to the power station. So the power cut is from the Bronco. Also, I wasn't thinking BMS since there every 10 seconds it tries to power the outlet and then cuts power but all other aux power such as the radio and lights are unaffected. Am I wrong in thinking this way?

 

[Brian_B]

I

I am not using a charger for the power station but connecting the power from the 12v cigarette port to the input to the power station. So the power cut is from the Bronco. Also, I wasn't thinking BMS since there every 10 seconds it tries to power the outlet and then cuts power but all other aux power such as the radio and lights are unaffected. Am I wrong in thinking this way?

No you aren't wrong.

BMS governs a lot of different things though - like how many volts to get from the alternator, if to enable/disable Auto Start Stop, it can disable the touch unlock, it can disable telematics and auto-updating, and it can disable power points (which are the 12V outlets, not just the 120V inverter on the upper-tier package) - among many other things you wouldn't necessarily associate with a battery controller.

It looks at voltage, it looks at amps in/out (which is why it needs to be hooked up and in the loop when charging), it considers temperature and a few other things and it tries to calculate "battery health" - and it can disable a lot of crap if it thinks the battery health is poor - even if it's perfectly fine. There is a full reset procedure for the BMS - but it's really intended to be used when you outright replace the battery and it resets Battery Health back to 100%

I can't think of any good reason why it would cycle every 10 seconds.... headlamps and some other loads have a "soft" fuse that can be reset by the computer like a circuit breaker, but I think the power points have a standard replaceable fuse.

And since I can't think of any good reason why it should be doing that, that leads me to the weird stuff - rebooting the ECMs and modules and ensuring the battery are topped off are kind of like the "reboot the modem" fix when the internet goes out.

One of my biggest complaints about the Bronco is when the BMS does start to disable stuff, it isn't readily apparent until it gets so bad you get to the "Deep Sleep" mode. Stuff just stops working, or goes wonky, and there really isn't any indication. There are a lot of posts about auto-updates stopping for no reason, ASS stops working, touch doorlocks stop working, power points not staying on per the settings, etc... and a lot of it ends up tracing back to just the BMS thinking the battery health is poor but not giving any indication of it.

 

[Dkirk]

I had a similar issue in my motorhome not my Bronco. The power shutting of every 10 sec sounded like my issue. Thought it was my cable running from 12v PowerPoint. After multiple power cord change outs I traced the the issue to a bad ground. Issue solved. Have you been doing any electrical work on your Bronco? The new phones are very sensitive to less than ideal power supply.

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