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OBC Onboard Charger issue

868 Views 40 Replies 4 Participants Last post by  Electric Tire Shredder
Hi all, new member here.

Woke up the other morning and discovered that the fuse for the garage had switched off during the night. The 500e was being charged via the outlet charger.
After switching the fuse back on, there was a notification on the instrument panel saying "service charger system", and something along the line "plug not being detected". At the same time the flagpost where flashing.
After trying another charger (charging box), disconnecting 12v and HV, there seem to be no way the car would like to accept charging. Note that car is fully drivable, but obviously it will run out juice in not too long if used.

When charger is connected, and this attempts to charge the car, there is a sound coming from the OBC as you can hear in this video clip.
OBC Video

Question is if this is sufficient to conclude that I have a OBC issue?
Does anyone know if a used unit is a "simple" replace procedure, or does it need to be coded to the car in any way?

Any tip you may have will be greatly appreciated!
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Wow! That's 2 charge-only failures within less than a week, seemingly caused by a voltage spike.

My first step would be to go through the list in post #3 here: HOW TO FIX A "DEAD" 500E that suddenly...

Then the list in post #1 of that same thread, & if it still won't charge, see if the codes that won't clear indicate the OBC.

The PIM is supposedly coded to the motor, but a used unit is a simple replace procedure, with no need to be coded to the car. The OBC is even less coded to the car, so it should also be a simple replace procedure.
There's a place in Poland that repairs BPCMs, who might also be able to repair your OBCM:
Repair Options if Easy DIY Fails. 5/18/23 Update: Fresno...

Even if they say no, you could send them the bad one so they can at least try, or maybe learn for next time.
Thanks ETS. Think I have tried all measures in the refereed post. Regarding obd, I understand the 500 is picky about type. Do you know a specific type that will work? Did you watch the video? Any thoughts about the sound coming from the obcm?
By memory, it sounds like mine, but I think it's the coolant pump.

500e isn't very picky about OBD, as long as you don't use one with its own screen. Veepeak or $17 eBay Konnwei KW902 will work for everything I've seen anyone need EXCEPT for the unpreventable flashing odometer which can make it die while driving :oops:. So I recommend getting a setup that works for that, just in case, & also one that you can always have available in the car, in case you get the contactor glitch that's also unavoidable & prevents the car from starting...
It's also in the footnote labeled " 2, 5 " of the first post of the "how to fix" thread.
It should be a wired one? Or is Bluetooth ok? What's this about yellow version?
It can be an OBDLink SX wire, if you can have the app on a USB device that's always in the car, such as an Android with USB-C & an adapter for the SX wire's USB-A plug.

OBDLink LX Bluetooth is ok, or MX+.

Yellow adapter only works with those OBDLink units or others that cost more...
Yellow adapter is only needed to access certain OBD modules, including the one to fix the flashing odometer.

I've never seen it needed for anything else, but since the flashing odometer can make it die while driving, I recommend getting an OBDLink just in case...
You could also get a yellow adapter just in case, since it's cheap but can take a while to get the right kind, as shown at post #2 here:

Trusted source for "Yellow" OBD adapter?
Keep getting the no data message with the obd's I have. Assume this is due to not being compatible. Will source a kw902.
If you plan to keep the car, I very strongly recommend getting an OBDLink SX or LX.
If you plan to keep the car, I very strongly recommend getting an OBDLink SX or LX.
What about the CX? How well does it work?

I got a KW902 & it worked fine until my odometer started flashing.

Many others have got that too, as shown by forum post titles. Its unavoidable, & it can make the % gauge suddenly drop to 0%, making the car die while driving.

Fixing that requires a yellow adapter, & that won't work with a KW902
What about the CX?
I wouldn't bet on it, just to save $10 compared to the LX.

Halfway down the home page it does say "OBDLink MX+/LX/EX/SX/CX",
HOWEVER, at the compatibility page it says only:

"Compatible with OBDLink MX+, OBDLink LX
Compatible with OBDLink EX, OBDLink SX"

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If I was doing it all over again, I'd just get the $50 SX cable & a sub-$10 USB-A to USB-C adapter to plug into my phone.
Thanks ETS. Think I have tried all measures in the refereed post. Regarding obd, I understand the 500 is picky about type. Do you know a specific type that will work?

It should be a wired one?

Keep getting the no data message with the obd's I have.
If you tried one with a wire to its own screen, that can cause malfunctions. I believe those malfunctions will clear with the steps here, using a Veepeak, or Konnwei KW902, however as noted above, I very strongly recommend an OBDLink SX cable or LX Bluetooth, depending on what device you have the app on that can be kept charged up in the car for emergency use:

HOW TO FIX A "DEAD" 500E that suddenly...
Not tried with wired type, so should be good there.
A friend of mine working in a garage will bring a pro type obd for reading the codes.
Is there a specific one that should indicate obc failure? Will I know without doubt?

The shop in Poland say they can fix it, 500euros, plus shipping.
Might be cheaper to get a secondhand from scrapyard, not too many lying around though.

Also, when working on the high voltage, is it sufficient to pick out the fuse under the back seat? Or is further isolation required?
I wonder what "pro type" code reader your friend has, since most pros I've seen have wires to their own screen.

A local driver here had her 500e fail & her friend working in a garage refused to believe his "pro type" wired-to-screen reader shouldn't be used. I can understand his disbelief, since it's absolutely ridiculous that any car could be made this way, but unfortunately it's true in this case.

I suggested to the driver that she tell the pro that even without lightning, or breaker cycling, or doing anything at all except drive & charge, this car can fail on its own, with the contactor glitch that causes failure to start or drive, or proxy misalignment which can cause stalling while driving. Fortunately those are both very easy to fix, with about $110 worth of tools.
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