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

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So you didn’t change anything, only new battery solved the issue, right?
Actually yes, recently i have charged main battery, but measured up my auxiliary battery in the end of charging cycle and it was 15,5 volts,I pretty sure that it is too much for it. Frankly,the charge was not finished yet,i decided to complete the charge, since the indlicator showed full. After a night, the voltage was 12.9 volts,it's ok.when car is in "ready" it shows 14.2 v,pretty good,like on non-electric cars.How many volts on auxiliary battery during charging by network do you guys have on it?
 
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Actually yes, recently i have charged main battery, but measured up my auxiliary battery in the end of charging cycle and it was 15,5 volts,I pretty sure that it is too much for it. Frankly,the charge was not finished yet,i decided to complete the charge, since the indlicator showed full. After a night, the voltage was 12.9 volts,it's ok.when car is in "ready" it shows 14.2 v,pretty good,like on non-electric cars.How many volts on auxiliary battery during charging by network do you guys have on it?
I believe it was 14.7 when I measured. 15.5 really sounds much. Extremely low temperature during charging could explain it probably. But I believe it is the same circuit that charges the 12V battery when the car is in the ready mode and when the HV battery is charging, so it sounds strange. Heck again when charging next time
 
Ok,got it.i'll check the voltage in the beginning of charging.yesterday i measured the battery after driving it was near 14,3 V.but ignition was OFF
What do you mean extremely low temperature?where?
I believe it was 14.7 when I measured. 15.5 really sounds much. Extremely low temperature during charging could explain it probably. But I believe it is the same circuit that charges the 12V battery when the car is in the ready mode and when the HV battery is charging, so it sounds strange. Heck again when charging next time
 
Environment--ambient air temperature. The charging voltage is raised a bit in cold weather.

But it sounds like your DCDC is putting out too high a voltage.
 
I am in Florida,here is hot like in hell)
So,yeah,it is pretty weird
I have a 8 amp charger , i will try to charge somewhere
 
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If the temperature sensor that is being used to adjust the DCDC output happens to be out of spec--it could be thinking that it's cold out even though it is hot as hell.

Also how sure are you about your volt meter? Calibrated? Expensive or HF?
 
I have spare parts for cap replacement in the Dog House and a few (should be working) OBC's in Denmark
And I can do the cap replacement. Done 2-4 of them by now.
Also have the OBD II Dongle for canIon, that via another app (Car Scanner) will reset codes.

And my 2011 I-MiEV is currently for sale, but I am not quitting this forum any time soon,
as I am great support for the Danish Ion, C-Zero, and i-MiEVs on Facebook.
Hej, hvordan får jeg fat i dig :) kunne godt være interreseret i stumper eller hjælp til rep :)
 
If the temperature sensor that is being used to adjust the DCDC output happens to be out of spec--it could be thinking that it's cold out even though it is hot as hell.

Also how sure are you about your volt meter? Calibrated? Expensive or HF?
Hello there, sorry for long answer
Now it's alright, i have normal voltage during charging, I don't know what it was, just kept going charging and once i left charging overnight, charging stoped by itself, and battery was full.i have another interesting issue. As i have an old main battery, car has approximately 30 miles range, but sometimes when it remains 6 miles i can't accelerate normally,top speed is 15 miles/h and "a tourtle" appears.but today i did already 35(!) miles range ,it remains 3 miles,but acceleration was good and tourtle appeared at 40 miles/hour.not big deal, just wondering why it happened
 
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sometimes when it remains 6 miles i can't accelerate normally, top speed is 15 miles/h and "a turtle" appears. But today i did already 35(!) miles range ,it remains 3 miles, but acceleration was good and turtle appeared at 40 miles/hour. Not big deal, just wondering why it happened.
I'd say that your cells are dissimilar in capacity. That means that one will get low first, usually when accelerating because that's when the load is the highest. The BMS should eventually learn about that low cell and reduce its estimated range to be more realistic. There isn't much that can be done about dissimilar capacity cells, other than replacing the worst ones. When dissimilar, you can balance at the top and have ragged bottom (early turtle), balance at the bottom and have ragged top (some cells can't accept regen).
 
2) As for the MOVs, do their specs have any bearing on what GDT to use? The originals in my charrger are Panasonic ZNR V20471U, which seems to have been replaced by ERZV20D471, shown here: https://www.digikey.com/en/products...31?s=N4IgTCBcDaIKYCcBeBaAbmADAEwCwHYBGEAXQF8g .
I finally figured out the varistor part numbering. The lead spacing (R for 7.5 mm and D for 10 mm) is in the manufacturer's part number, but missing from the number on the device!! So the above seems to be the correct part number, as the boards have 10 mm pad spacing and 3.5 mm offset (pads are at the corners of a 10 x 3.5 mm rectangle).

So the full Panasonic part number is ERZ-V20D471, and the DigiKey part number is P7234-ND. For Australian readers, the link is P7234-ND .
 
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My version of the Waffle Plate™ diode drop diagram. The forum software seems to resize the image. Full size image [edit link, here ].

1712406789549-png.454
I'm trying to access the full size image but the original "does not exist anymore", is it available somewhere else?
 
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[ Delete this line! This post is a candidate for replacing the first index post, with links corrected. A big chunk of it was copied from the AEVA index page. ]

[Edit Jan 2024 The forum software was updated and the page numbering is now different, some links may not be anchored correctly (tbd)

Also there is now a 10,000 character limit, so this post had to be broken into parts.
part 2 here: #1,264
part 3 here: #1,263
/edit]

This thread will be used to document the technical information and any schematics or firmware available to help troubleshoot and repair the OBC/DCDC Converter

Post #2 has troubleshooting steps and an index of this thread

Post #3 will hold a collection of circuit schematics

[edit Sydney EV video link showing a snubber capacitor repair with OBC removal]
Sydney EV video of iMiev charger repair

[Original post June 2018] There seems to be many failures reported lately (last 6 months or so)

Links to user's failures [and successful REPAIRS] in reverse order, latest at top:
[2023 edit]
##. Coulomb (July 2023). 2010 earlier version OBC in Australia. Failed isolation amplifier board in the Output Sense and Filter section beginning on page 110. Successful Repair by Coulomb

##. Philsuth (Aug 2021). Investigation of a 2010 earlier version OBC in Australia. Complete disassembly with some great details and pictures beginning on page 76. PhilSuth

[2020 edit to add additional repair efforts]
##. LucasH (Nov 2020). Does not charge, but DCDC is working. LucasH

##. ZetaFunction (July 2020). Sebastian's issue with the switching power supply on the bottom board, a new issue never seen before starts here: ZetaFunction on pages 54-59 still in progress.

##. DutchLincoln (June 2020). Great pictures of disassembly to repair damaged snubbers.
DutchLincoln

[previous list]
21. 11/28/2018, Reports and more repairs by Skylogger in WA

20. PM message, 10/2018, from tdigsi; looking for substitutes to replace the 680 and 220uF capacitors?
[EDIT: REPAIRED, replaced snubber caps and MCU fuse, now it is charging; going to replace HV caps anyway due to age and high mileage, est. >~5000 Hrs on caps.]

19. PM message, 9/2018, from Quixotix in Seattle; dealer says charrger is dead; recommended to request DTCs and open cover to inspect for damage, blown fuse, etc.

18. ChristopheFR, 9/2018, 2011 C-Zero in France, EVSE charging appears to start then quits, DCDC appears to work ok, Aux battery changed in 2015

17. skylogger#2, 9/2018, 2010 in Western Australia, blown snubber caps and MCU fuse, AC relay and precharge Rs
[EDIT: REPAIRED--SUCCESS!, 9/2018 ]

16. footswitch, 9/2018, 2012 not charging in Portugal, EVSE charging appears to start, then just quits, DCDC appears to work ok, still running with OEM Aux battery.

15. charliejuliet, 8/2018, failed charrger in Michigan UP, replaced with aftermarket DC/DC and Chademo charger.

14. redcane, 8/2018, 2010 not fully charging in Australia (east coast), OBC was replaced with a 2015 unit under recall in January 2017.
[EDIT: 1/8/2019,REPAIRED, replaced snubber caps and MCU fuse. Also replaced the pre-charge resistor, but that was not due to the OBC failure.]

13. skylogger, not charging in Western Australia, found blown surface mount capacitors.
[EDIT: SOLVED AND REPAIRED,8/12/2018, see picture of a twisted resistor causing open circuit on voltage monitoring]

12. beeline, 6/18, 2012 not charging, dealer estimates $4800+tax

11. mikedufty, 3/18, 2010 Australian model not charging fully in WA, charrger was replaced under recall. Dealer now pointing at EV-ECU as bad.

10. 1pk, intermittent charging level 1 and 2, found cracked bypass resistors at AC relay
[SWAPPED OUT OBC WITH USED 2013 UNIT, 8/13/2018]

9. Lic, 4/18, getting condenser timeout error P1A15, no main(+) contactor indication

8. jray3, 6/18, Mr. Bean dc converter not working, blown 20A fuse in the inverter

7. luvmymiev, 6/18, Category: i'll take bad charrgers for $4000--The question is:What did the dealer find?

6. electronpusher, 6/18, car not charging in New South Wales, blown snubber capacitors in the potted doghouse and fuse in the MCU.
[EDIT 10/7/2018: REPAIRED , replaced snubber caps and fuse and now it's working again, Good Job!]

5. Antaris, 3/18, service manager says the on board charging unit has failed.
[EDIT: REPLACED, Mits Canada replaced it for $800 Cdn]

4. fresnomiev, 3/16, dealer replaced charrger while troubleshooting by parts swapping, issue was MCU inverter.

3. pluto, 2/18, code 39 OBC, abnormal PFC voltage,

2. Sbess, 10/17,dealer says bad charrger

1. TorranceMiEV, not charging

iDriver, Nov 28, 2017, charrger fuse in MCU blown


Just for the historical record, mccluer had a very early report of charrger failure back in 2012

also DonDakin in 2013

also Malm, 3/2016


===
[edit: add a section of pictures of various items frequently referenced]

This shows the OBC on the left with the cover off and the upper control board removed showing the power board and flat ribbon cable, and the MCU on the right with the access cover open:
oNjGAeQ.jpg


MCU with cover open
833ozoP.jpg




Here is an OBC picture with the cover open, note scorch marks on inside cover and the full exposure of the tops of the electrolytic capacitors (credit to coulomb for pointing out this indicator of high temperatures):
OD2diIc.jpg


2015 version
83XRF4b.jpg



EMI Filter DogHouse (External Box on some versions)
uO22iKp.jpg



DCDC Converter Board in the bottom plenum from this post, http://myimiev.com/forum/viewtopic.php?f=23&t=4079&start=20#p36638
bLNOfTC.jpg
 
[ Delete this line! This is a candidate replacement for post 2 of this thread. ]

Here are some links for easy things to check:
1. 12V Aux Battery Test
2. Check or Replace OBC and EV-ECU relays in the fuse box
3. Check OBC power supply

Connectors make for quick and easy installation, but they are the most likely candidate for intermittent issues. The sliding contacts are prone to oxidation and dirt. Sometimes just disconnecting and cleaning the contacts with spray can of cleaner compound will provide a fix. With key OFF, just pull all the connectors on the EV-ECU and the BMU and clean all of them.

Troubleshooting Links:

Step 1: Diagnostic Trouble Codes from EV-ECU concerning OBC DTC for OBC

Step 2: DTC for the DC/DC Converter DTC for DC/DC

Step 3: Internal Trouble Code List for OBC OBC trouble codes

Step 4: At this point the dealer has no real repair options but to sell you a new box, or you can find a used one and replace it--it will work without any VIN re-coding needed according to jray3, who did this himself, or you can open the box and inspect for missing/burnt parts and we can try to fix it here. or maybe you could send it to an expert in Australia (coulomb or skylogger), or in USA (piev or kiev). It's heavy, ~27 lbs.

Another option may be to altogether replace the OEM charrger and converter with an aftermarket solution, such as was done here by charliejuliet.

The final option is to post your codes here and we will try to help you troubleshoot and repair your OBC.

HOW-TO Section
1. Coulomb instructs on how to release the flat ribbon cable connectors without damage: link.
2. Coulomb on measuring the pre-charge resistors while the bottom board is in place: link.
3.

Index:

1. Thermal imaging during charging FLIR images

2. What's touching the heatsink? Bottom Board

3. What's inside it? Waffle Plate™
Another view from IFAM recently posted here Here. Also one from the 2010 model marked up. The X-ray of the Waffle Plate™, and a second, smaller X-ray without the overlaps. Also an X-ray of the 2010 high voltage mini Waffle Plate™.

4. DC Bus Capacitors Swollen Caps and Precharge Simulation


Schematics and stuff:

1. AC Input Filter and Relay. Coulomb's version has a few more parts designators.

2. Output filter, original version, and within a block diagram.

3. Solder Pads to Waffle Plate
a better version is here:

3.1 Diode drops in waffle plate, and Coulomb's version.

4. Low Voltage Supplies and Relay Drive description

5. Control (Top) Board Voltage Supplies discussion/measurements on page 9

6. Bottom Board AC detection circuit sketch

7. Output HV and Current sensing circuit sketches (related to skylogger's twisted sister resistor finding)

8. OBC connections and E-03 connector wiring

9. ph

Notes of parts links:

Pictures and specs for blown snubber caps, Optional caps

for TAM ceramic resistors datasheet link,

PEC 20A 450VDC MCU fuse: Available from dealer parts dept; See also the Fuse Investigation thread for the OEM datasheet (post 3) and an equivalent Littelfuse 0HEV020.ZXISO available from Mouser, link

and Fujitsu AC relay datasheet; original https://www.fujitsu.com/downloads/MICRO/fcai/relays/ftr-k1kw.pdf no longer works; Archive.org copy. This post discusses replacement options.

The Panasonic varistor part number.

12V Aux Battery Notes and Links

Simon's excellent observations and testing: link

IGBT part numbers for the 2010 high voltage mini Waffle Plate™.


FSM testing:
http://mmc-manuals.ru/manuals/i-miev/online/Service_Manual/2012/54/html/M154100120213701ENG.HTM

Charging:
http://mmc-manuals.ru/manuals/i-miev/online/Service_Manual/2012/54/html/M154100110201101ENG.HTM

Removal and Installation (precautions for disconnecting negative terminal and extended d/c):
http://mmc-manuals.ru/manuals/i-miev/online/Service_Manual/2012/54/html/M154100230004500ENG.HTM

DTCs related to aux battery:

Low supply voltage (C2005,2006 DTC for EV-ECU):
http://mmc-manuals.ru/manuals/i-miev/online/Service_Manual/2012/54/html/M154920130001700ENG.HTM

High supply voltage EV-ECU, DTC C2007:
http://mmc-manuals.ru/manuals/i-miev/online/Service_Manual/2012/54/html/M154920150001100ENG.HTM

EMCU low supply voltage, DTC P0562:
http://mmc-manuals.ru/manuals/i-miev/online/Service_Manual/2012/54/html/M154930140001101ENG.HTM

OBC low supply voltage, OBC code 04:
http://mmc-manuals.ru/manuals/i-miev/online/Service_Manual/2012/54/html/M154955050003600ENG.HTM


Other aux battery related codes:
DCDC Converter, DTC P0A09:
http://mmc-manuals.ru/manuals/i-miev/online/Service_Manual/2012/54/html/M154920520002300ENG.HTM

ASC Traction controller, abnormal voltage readings (DTC):
http://mmc-manuals.ru/manuals/i-miev/online/Service_Manual/2012/35/html/M135500490016101ENG.HTM


ph
 
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