The Troubleshooting and Repair for On-board Charger (OBC) Thread

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So, on my quest to get the OBC replaced, I found a 2016 charger in a salvage yard as posted above, but it was a Gen1 charger (EMI box on top). I believed any of them made after 2012 wouldn't have the waffle plate, but I want to have the car on the road, so I took it. This 2016 one comes with the little PCB instead of the two snubber caps, little board was burnt. It looks like all the drops in the waffle plate are good so it might just be the snubber caps which I'll receive today. Fingers crossed!
 
Hi , what kill électronic is often vibration and bad connection, so if you leave the capacitor without the black goo the might vibrate on the long run while driving the car and will probably be defective again .
 
Привіт позвони 0963020624

Another PM from Pavlo:
@Pavlo :
Hello, I became the owner of i-MiEV, everything worked perfectly, drove 126 kilometers.
But two weeks ago, problems started. There were errors u1116, p1A7E, P1A66, P1A33, P1A31, P1A39, P1B04.
In the process of more detailed diagnostics through OBD C ZERO, it was found that the temperature of 52 degrees is too high in CMU 9 in one of the cells, it was decided to replace the board on this unit with the same one from a used one. car.
After the replacement, the car drove, but soon the same problem appeared on the CMU 10, the board was replaced with a used one. All 88 cells were balanced, lowest voltage 4.05V, highest 4.07V, lowest cell resistance 1.17mΩ, highest 1.20mΩ.
After installing and connecting the battery, the car refuses to charge and there are errors u1116, p1A7E, P1A66, P1A33, P1A31, P1A39, B1105, everything points to a faulty CMU9 board in cell F 329.78329.78 V. I am attaching a photo of the reports.
Can you help or direct me to a discussion thread on this forum? Because I don't know what to do next?
 
Hi , what kill électronic is often vibration and bad connection, so if you leave the capacitor without the black goo the might vibrate on the long run while driving the car and will probably be defective again .
Why just those Cs and none of the other components ?
Are they carrying hf which might cause a tiny vibration ?
A bit like domestic AC sockets "unscrewing" the mains connections over the years ?
 
Another PM from Pavlo:
@Pavlo :
P1A66 -CMU09 Battery Cell High Voltage abnormal
PROBABLE CAUSE - The module (battery cell, CMU and battery cell voltage sensor) in the main battery is failed.
P1A7E - CMU09 battery cell voltage sensor abnormal
PROBABLE CAUSE
The module (battery cell, CMU and battery cell voltage sensor) in the main battery is failed. or The BMU is failed
P1A31 - Cell voltage abnormal high (BMU) The procedure for the next 3 is to check the CAN Bus between EV ECU and BMU. But probably due to CMU errors
P1A33 - Cell voltage sensor error (BMU)
P1A39 - Charging state signal error (BMU)
P1B04 - Maximum cell voltage abnormality during charging - Malfunction of BBMU or Main battery most likely due to CMU errors
 
I wanted to thank the folks in this Forum, especially Kenny and Coulomb for their wise advice. My I-Miev is back charging, repaired solely with the information provided here. You guys rock!
 
My version of the Waffle Plate™ diode drop diagram. The forum software seems to resize the image. Full size image here.

1712406789549-png.454
 

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Hello. I write and read through a translator, many things are not clear. The pictures don't open for some reason. The car stopped charging from the home network. I changed the fuse 20A 500V. I rewired the capacitors c121 and c122. Visually, the rest is all whole. Error P1A12. I checked, supplied power to the diode, the resistance changed from 9.6 to 0 ohms. that is, the resistors are intact. How to check the capacity that is near 310v 22mkF?
 
I now believe that the resistor in the Waffle Plate™ between pins 15 and 16 is not 0, but around 3.3 mΩ, based on around 9.8 mV measured at the end of the pins when I pushed 3.0 A into the pins low down. There seems to be an op-amp near these pins:

1713182860209.png

This emphasises the importance of not shorting pins 15 and 16 when re-soldering the Waffle Plate™; the same goes for pins 7 and 8. These pairs (15,16 and 7,8) appear to be the "voltage" terminals of the four terminal shunt resistors. The bulk of the current flows through the nearby pins, but as far as I can see, these sense wires connect directly to the edges of the SMD resistors.

You can more or less see this in the bottom left of the X-ray photo.
 
a PM from Serhiy2192
Hello Kiev!Sorry for bothering you,just would like to ask you about converter.i have a problem with my i-miev.it doesn't charge.it happend (i just assuming) after a couple times after fast charge using a chademo plug on regular city charger(then i have charged those 2 times using an original 120 v mitsubishi cable,it made a full charge,but with yellow led and pretty bad smelling in the trunk) i have heard that it's pretty common problem for this car.after removing the cover, I saw a burnt area on the cover as in your photo, but the wires, fuses, transformers all seem to be intact. also everything looks normal in the area of the blue capacitors (usually they are changed and everything is ok).I have not yet looked at what is happening under the second board, maybe the consequence is there.what do you think where to look next and what is the reason overheating? a faulty charger due to a voltage surge or something else? I'm still thinking about a pump that drives the coolant, but it's unlikely.
sorry for a lot of text))
Howdy @Serhiy2192, i am posting your message here so that everyone can benefit.

The scorched marks on the top cover are normal--the inductors inside the charger get quite hot while in action and the clear plastic insulation on the wire out-gasses and deposits on the lid. The coolant pump should be running during charging; if it's not then that is a problem.

The Chademo has no connection to the On-board Charger--it is totally unrelated to charging from the AC mains. Different plug, port, wires, contactors, controller, etc.

The most common faults in the OBC are either on the AC Input section, or in the HV DC Output section. Pictures of those faults can found on page 1 of this thread. You will need to unscrew the fasteners holding the upper control board to carefully lift and lean it over out of the way to inspect for damage.

Post up some pictures if you find something.
 
ПП від Serhiy2192

Привіт @Serhiy2192, я публікую ваше повідомлення тут, щоб усі могли отримати користь.

Обпалені сліди на верхній кришці є нормальним явищем: котушки індуктивності всередині зарядного пристрою стають досить гарячими під час роботи, а прозора пластикова ізоляція на дроті виділяє гази та відкладення на кришці. Під час заправки насос охолоджуючої рідини повинен працювати; якщо ні, то це проблема.

Chademo не має підключення до бортового зарядного пристрою - він абсолютно не пов'язаний із заряджанням від мережі змінного струму. Різні вилки, порти, дроти, контактори, контролери тощо.

Найпоширеніші несправності в OBC є або в секції входу змінного струму, або в секції виходу високої напруги постійного струму. Фотографії цих несправностей можна знайти на сторінці 1 цієї теми. Вам потрібно буде відкрутити кріплення, що тримають верхню панель керування, щоб обережно підняти та нахилити її, щоб перевірити наявність пошкоджень.

Опублікуйте кілька фотографій, якщо щось знайдете.
Thank you!)apreciate it!
 
Also check the pre-charge resistors. I have a photo somewhere of the two points to check between for around 9-10Ω, but can't find the photo. Sigh. I'm pretty sure it's neutral on the pins of the Waffle Plate™ and at the neutral input. Edit: Found the link.

1714095512119.png
 
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Also check the pre-charge resistors. I have a photo somewhere of the two points to check between for around 9-10Ω, but can't find the photo. Sigh. I'm pretty sure it's neutral on the pins of the Waffle Plate™ and at the neutral input. Edit: Found the link.

View attachment 519
Thank you!i checked the resistance between 1 point(near blue capacitors) and each of 4 points N ,it is 10,2 Ω

All 3 boards and radio elements seem to be intact. I checked the inductors on the large board, they all have a resistance of about 0.7 Ω,so I think there is no inter-turn shorting, but the stench comes from them. all the fuses are intact.I cannot check ceramic capacitors, have no special device

the ordinary charger 120 v 8 a looks good, when it's connected to the outlet without a car, a green lamp lights up, I don’t know how to check it, maybe the main reason was on it, after the last charging, the false yellow lamp was on. maybe the voltage in the network jumped, I wonder how much volts more than 120 is critical for my charger, cause sometimes the network shows 119-122,I think it is not significant.nobody knows how many was in this moment.but I tried to charge from other chargers in my city, the same story
 

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Were there any trouble codes thrown, DTCs read out by a scan tool?

What is the age and condition of your 12V battery? An old, weak or worn out battery can cause faults that prevent charging.

Did you try a different EVSE unit for AC charging (to rule out an issue with the mains power or the EVSE)?
 
Were there any trouble codes thrown, DTCs read out by a scan tool?

What is the age and condition of your 12V battery? An old, weak or worn out battery can cause faults that prevent charging.

Did you try a different EVSE unit for AC charging (to rule out an issue with the mains power or the EVSE)?
the battery is bad, about 30 miles on a full charge, it's about 50% capacity I suppose, I was already planning to do something about it, but here is this charging problem appear
unfortunately I didn't scan it, there were no errors on the dashboard, it was a very dump decision , I understand)) I might collect everything back and scan it, I don’t have a scanner exactly for this car, please advise some,or software for Pc,I saw several, but I can’t choose. I tried to charge from city stations, doesn't charge

12 v baterry ,i 'll check it ,let you know
 
yes, indeed, the 12-volt battery is already dead, now it shows 10.5 volts, although I drove it a one week ago, it should have been at least 11 with something, or even 12. it looks swollen, electrolyte is pouring from the nozzles. It arrived. I'm not surprised,cause the car was parked for a long time without driving, previous owner charged it before selling,because the car simply wouldn't start. I bought it about 3 weeks ago. That's the story. Thanks for the hint)
 
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The 12V battery is critically important for an EV, and not something you want to skimp on, or play around with trying to squeeze the last bit of use out of--it can result in expen$ive damage to nearly unavailable components.

Check the fuse under the access cover of the motor control unit aka drive inverter, located to the right of the OBC. If that fuse is blown then the DCDC converter located in the bottom plenum of the OBC will not get power to recharge the 12V battery, nor will it allow the OBC to charge the main HV pack (traction battery).

Nothing obviously blown in the OBC, eg precharge resistors, snubber capacitors. i suspect the bad 12V battery may be the root cause of your problem. Remedy that first, then try to drive/charge your car.

You could do the waffle plate diode drop checks while you have that power board out and disconnected, see coulomb's post #1308 on this page for a diagram with expected voltage drops.
 
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The 12V battery is critically important for an EV, and not something you want to skimp on, or play around with trying to squeeze the last bit of use out of--it can result in expen$ive damage to nearly unavailable components.

Check the fuse under the access cover of the motor control unit aka drive inverter, located to the right of the OBC. If that fuse is blown then the DCDC converter located in the bottom plenum of the OBC will not get power to recharge the 12V battery, nor will it allow the OBC to charge the main HV pack (traction battery).

Nothing obviously blown in the OBC, eg precharge resistors, snubber capacitors. i suspect the bad 12V battery may be the root cause of your problem. Remedy that first, then try to drive/charge your car.

You could do the waffle plate diode drop checks while you have that power board out and disconnected, see coulomb's post #1308 on this page for a diagram with expected voltage drops.
Apreciate it,Kiev
I've checked this fuse first of all before disassembling the OBC.it's ok

Good,I will put everything back together, and install a new 12v battery and try. I will write about the result
 
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