coulomb
Well-known member
Yes, I'm guessing lower ESR, and possibly it's hard to get 100 nF at 500 V in a single, reasonably sized SMD component that works with their pick and place machine.philsuth said:
The Troubleshooting and Repair for On-board Charger (OBC) Thread
- Thread starter kiev
- Start date
Help Support Mitsubishi i-MiEV Forum:
I'm making progress on the slow road to proper reassembly. I'd hoped to solder a chip capacitor in place of the original destroyed one, but a couple of hours of widening the pit in the waffle board and attempting the job convinced me that it wasn't going to work - at least at my soldering skill level. There is just too much heatsinking to make reasonable joins to a surface mount component in the confined space available.
Instead I have acquired a 630V (brown) greencap through hole capacitor, and connected it on one side to the pad where the chip capacitor was removed, and on the other side to the base of the connector to the boost inductor - electrically equivalent but easier to get to . I've made good solid solder joints on each side and the combined capacitance is as expected. Here's what it looks like:
After talking the photo I filled the pit with a capful of the two part silicone potting compound I'm going to be using on the top board - Chemtools PCT7000 - and after gently oven baking the module at 65C for 2.5 hours to cure it looks like this:
Tomorrow I solder the top board back in place again, do a retest to ensure I've not broken anything, then repot the top board, cure, and perform final reassembly and test. That's if all goes to plan....
Instead I have acquired a 630V (brown) greencap through hole capacitor, and connected it on one side to the pad where the chip capacitor was removed, and on the other side to the base of the connector to the boost inductor - electrically equivalent but easier to get to . I've made good solid solder joints on each side and the combined capacitance is as expected. Here's what it looks like:
After talking the photo I filled the pit with a capful of the two part silicone potting compound I'm going to be using on the top board - Chemtools PCT7000 - and after gently oven baking the module at 65C for 2.5 hours to cure it looks like this:
Tomorrow I solder the top board back in place again, do a retest to ensure I've not broken anything, then repot the top board, cure, and perform final reassembly and test. That's if all goes to plan....
This morning I soldered the module back together again, then put it back in the vehicle. I ran a charging test for about 5 minutes, just long enough to feel comfortable that I hadn't broken anything else. I then pulled the module out again, put the plastic wall back in place on the top board and secured it with a few drops of super glue, then repotted with the rest of the compound from yesterday. I gently warmed the module for 2.5 hours at 65C, and peeled off the little splashes and overflows easily afterwards. It looks almost as good as new.
Reassembled afterwards, went out for a much anticipated drive, then recharged again. All went well - after a little over two months I finally have my iMIEV back in action.
Huge thanks to all who followed along, commented and made suggestions, and especially to those who did all of the earlier reverse engineering work on the charrgers. While this particular unit was a little different in form, practically it was very similar, and the job would have been far harder without all of that work.
Reassembled afterwards, went out for a much anticipated drive, then recharged again. All went well - after a little over two months I finally have my iMIEV back in action.
Huge thanks to all who followed along, commented and made suggestions, and especially to those who did all of the earlier reverse engineering work on the charrgers. While this particular unit was a little different in form, practically it was very similar, and the job would have been far harder without all of that work.
Bravo! Great work on getting it repaired.
Is that potting compound something that could be easily removed if necessary?
Is that potting compound something that could be easily removed if necessary?
kiev said:
Thank you.
The potting compound is very similar to the original one used for the upper board, other than the colour of course. It hardens into a silicone rubber which can be dug out fairly easily. I was surprised how well it worked.
iOnico
Member
Some months have gone by since my last post. This post should be (hopefully) the final resume of my repair, as the car is charging again! The news isn’t that new as, after the repair had been done, I have observed the car for quite a while to see if everything works reliably. Having had two setbacks in situations where I thought that I had fixed the issue made me become careful with announcing victory too early...
First setback was when I thought that I had only the "classical" snubber caps issue and after replacing them the car still wouldn’t want to charge. The second one was after a long troubleshooting on the control board and the discovery of many damaged ICs I finally completely replaced the control board by another one. It was not 100% identical, some components were not in the same order, even if it was the same chips. So, at this point I can’t say if the failure of the repair was due to overseen damage on the power board (seems to be the more likely explanation) or if it was due to incompatibility of the replacement control board (seems to be the less likely explanation).
So, my repair finally ended as an easy “plug & play” repair. Due to a lack of knowledge, experience, good soldering and testing equipment and a complicated damage scenario with damage on many ICs of the control board and probably also one or more undiscovered damage(s) on the power board, this turned out to be the most implementable solution for me: getting an identical OBC box form a scrap yard as a donor and exchanging the two boards. That worked...
After the repair the car was announcing a much higher range expectation than before. I thought that this could be somehow due to the fact that the 12V battery was weak before and that it was providing a bad reference voltage, but actually this explanation didn’t satisfy me. I got the correct explanation after some days, when the little turtle icon went on and I had to call a neighbour to tow me the last 3 km home: obviously the calibration of range expectation and state of charge (SOC) aren’t correct any more. When the turtle icon went on, the car was announcing 15 km of remaining range and 2 remaining bars on the SOC. I assume that this wrong calibration is due to disconnection of the main and the 12V battery during longer periods while the car was waiting to be repaired and that it will correct itself with time and charging/discharging cycles.
That’s it. I want to thank all the people that have contributed to gather the knowledge in this forum and especially those who actively helped me by answering my questions during my repair journey.
First setback was when I thought that I had only the "classical" snubber caps issue and after replacing them the car still wouldn’t want to charge. The second one was after a long troubleshooting on the control board and the discovery of many damaged ICs I finally completely replaced the control board by another one. It was not 100% identical, some components were not in the same order, even if it was the same chips. So, at this point I can’t say if the failure of the repair was due to overseen damage on the power board (seems to be the more likely explanation) or if it was due to incompatibility of the replacement control board (seems to be the less likely explanation).
So, my repair finally ended as an easy “plug & play” repair. Due to a lack of knowledge, experience, good soldering and testing equipment and a complicated damage scenario with damage on many ICs of the control board and probably also one or more undiscovered damage(s) on the power board, this turned out to be the most implementable solution for me: getting an identical OBC box form a scrap yard as a donor and exchanging the two boards. That worked...
After the repair the car was announcing a much higher range expectation than before. I thought that this could be somehow due to the fact that the 12V battery was weak before and that it was providing a bad reference voltage, but actually this explanation didn’t satisfy me. I got the correct explanation after some days, when the little turtle icon went on and I had to call a neighbour to tow me the last 3 km home: obviously the calibration of range expectation and state of charge (SOC) aren’t correct any more. When the turtle icon went on, the car was announcing 15 km of remaining range and 2 remaining bars on the SOC. I assume that this wrong calibration is due to disconnection of the main and the 12V battery during longer periods while the car was waiting to be repaired and that it will correct itself with time and charging/discharging cycles.
That’s it. I want to thank all the people that have contributed to gather the knowledge in this forum and especially those who actively helped me by answering my questions during my repair journey.
haloo from georgia.
my country is near from the russia.
we have some nissan leaf in owre country.
I have problem with obc onboard charger on nissan leaf 2011 year.
problem is that my home charger not charges vehicle. i have other home charger, it do same.
we have not good repairmans, one of them says thet onboard charger that is back in the car is bad, i changed it myself. vehicle warks good. but i want repair old OBC block.
if anyone can tell me, from what i bigin repairings. whare i can search problems in onboard charger?
i allready open the cover off.
Top (Control) Board seems very well. there is not eny problems that i can see.
please halp me to search the problem in this OBC block.
my english is not so good as I want, excuse me for this.
Sorry for my poor English.
my country is near from the russia.
we have some nissan leaf in owre country.
I have problem with obc onboard charger on nissan leaf 2011 year.
problem is that my home charger not charges vehicle. i have other home charger, it do same.
we have not good repairmans, one of them says thet onboard charger that is back in the car is bad, i changed it myself. vehicle warks good. but i want repair old OBC block.
if anyone can tell me, from what i bigin repairings. whare i can search problems in onboard charger?
i allready open the cover off.
Top (Control) Board seems very well. there is not eny problems that i can see.
please halp me to search the problem in this OBC block.
my english is not so good as I want, excuse me for this.
Sorry for my poor English.
The miev and leaf OBC do have many of the same components. i would recommend that you post some high quality pictures of your boards over in the leaf forum, for example over in this thread with other repair activities, and i will give you some help over there:
https://mynissanleaf.com/viewtopic.php?f=30&t=28009&p=590974
https://mynissanleaf.com/viewtopic.php?f=30&t=28009&p=590974
I still have same problem 4,7Om resistor died again. It worked from last repair around 1.5 months. As I see in smart plug history, car was charging around 3 hours and on one moment power of charging went from 1.32kwt to 180 wt and after few minutes charging stopped. So I believe something happened with relay, it did disconnected and charging continued through resistors and one of resistors died. I don't understand why relay did disconnected but charging continued. I checked relay again- it looks fine, connects and disconnects without delays, without any increased resistance. Should I change relay anyway? What could be else wrong here?
coulomb
Well-known member
I assume that the relay signal must go through the ribbon cable. Those things can be cracked, or the connection at either end could be dodgy. Perhaps consider bypassing just the relay signal with a separate wire and sturdy connector; see if that makes it last.Lic said:
I suppose it could also be the power wires, and their chassis return. So maybe make it a 3-core cable/ribbon and 3-pin plug/socket. But power seems much less likely, because the charge continued.
@Lic, i don't remember if the snubber caps blew in your OBC, but we have been seeing many folks with splatter damage to the bottom of the control board such that the OBC won't function properly even with the snubber repair. i could imagine molten metal causing shorted or intermittent circuits and other faults.
Hi kiev,kiev said:
Thanks to remember me about it. I checked molten metal on back side of control board before and didn't see anything, but I will try to look again.
Right now I am waiting for new relay plus I think I will solder wires to resistors places and I will extend resistors by wires to be able to change resistors without main board removal. And I am searching for cheap used main board.
Hello, everyone
I just registered.
To the point: Defective OBC on I_MIEV Bj. 2011.
OBC 02/08/2011, with external EMI filter attached on Top of Case.
Visible defect on the blue capacitor C122 (one of two) which lies next to the relay center in the cast module on the lower board.
see link:
Mitsubishi i-MiEV On Board Charger (OBC) repair.
MIEV_OBC repair newer year of construction (Bj. 2011.12.25)
Here the module below with the power semiconductors has been removed to
replace the blue C121 and the green C122 with 2 new blue ones
https://www.youtube.com/watch?v=WVyXuSkn4jc
My circuit board has been removed, the black mush removed in the relevant area.
I checked the defective capacitor and carefully crumbled it to get its PINs free and save them in full length.
Reason: solder the new one to these pins to avoid soldering from below, because in addition,
the module below with the power semiconductors would have to be removed (56 solder points ! )
If I look at the soldering pattern of the 2 free PINs, then I am relatively sure, that the holes are vias (plated through)
So unsolder the pins and solder in the new component from above?
The distance between the capacitor and the circuit board would be 2 mm longer.
(A rough calculation with an inductance of around 1.2 nH per millimeter of cable length can be calculated. (Thanks to wikipedia)
So that shouldn't be a problem?
User Simon seems to have done it because of the soldered image.
Has replaced the 2 blue capacitors with 2 orange ones.
link
http://myimiev.com/forum/viewtopic.php?t=4079
Down the page to the photo series and then to the photo with the heading:
Beautiful Snubber Repair Job by Simon
(on the photo above, with the heading: Bottom Board "DogHouse" - the fenced-in potted area,
you can also see how my "DogHouse" looked like when it was still OK)
Although the second blue capacitor C121 is optically OK, I would also replace it.
2kV, 1000pF 1000pF = 1 nF ceramic capacitor
I documented all the steps with photos, which I will send on at the end of the repair. to:
https://www.goingelectric.de/forum/ and http://myimiev.com/forum/.
After reading a lot in https://www.goingelectric.de/forum/ and http://myimiev.com/forum/.
I examined other vulnerable components for possible defects:
The 2 ceramic resistors component R105 (the larger one) and component R106 (the smaller one)
Component R105 (the larger one) P10K TAM (manufacturer TAMURA) 4.7 Ohm J, 157 ° C.
Looks like new.
Measurement infinite Ohm = interruption!
I stripped the component carefully forensically to see internal defects.
P10K TAM (manufacturer TAMURA) 4.7 Ohm J, 157 ° C 105 (meaning of 105 unknown).
The 157 ° C relates to the trigger temperature of the integrated thermal fuse.
Although this has a declared current carrying capacity of 15A at 250V, it is pure
non-resetting temperature fuse. This is defective.
The wirewound resistor is OK.
Component R106 (the smaller one) 7K TAM (manufacturer TAMURA) 4.7 Ohm J, 105 (meaning of 105 unknown).
Optically OK, only 1 slightly brownish spot.
Measurement infinite Ohm = interruption!
Component carefully forensically stripped to see internal defects.
The wirewound resistor has partly burned out.
Wire diameter both approx. 0.40 mm
So both, probably 5 W.
I measured the 2 ceramic resistors in the installed state, through the narrow gap to the waffle plate module with the power semiconductors.
Used the following kitchen tools from my wife, as measuring tips:
2 x beef roulade skewers made of stainless steel Dm = 1.5 mm L = 100 mm, super-pointed. You can get any PIN.
Component K ??
Relay F + T (manufacturer) type: K1AK005W-KW 5Vdc 16A, 277, VAC RES.
Contact symbol for 1 contact NO, 16A 250VAC.
1040L2 China with VDE mark
Measurement of relay contact, resistance infinite = OK. Relay contact not glued.
Measured at the end of the series connection R105 - R106. Between # 11 and # 14 on user kiev`s circuit diagram.
Measurement relay K ?? Relay coil 5V, 59 Ohm, 85 mA and 0.43 W, energized with source 5V sc 300 mA
(for safety reasons source with small sc)
Energized at the free-wheeling diode D301, positive pole at the diode bar.
This freewheeling diode is missing on user kiev`s circuit diagram.
Relay clicks and contact closes with 0 ohms. Relay OK.
Although the MP capacitor C106, 2.2 µF, 310 VAC, optically is TOP, I also change it to be on the safe side. .
Removal:
The black mush, removed in the relevant area.
I removed the gray wall of the potting module on the small side of the capacitor, (gray wall can be glued on again)
The capacitor, sawn, blown, tattered. Horrific work. :mrgreen:
With an 12V craft drill, with a 2 mm grinding drill, I exposed the pins on the stripped floor.
Undercut the bottom of the capacitor, along its entire length with a fine, long cutter knife to solve it from the circuit board.
Get the 2 PINs in full length L = 14mm.
TIP: It's a lot easier.
Remove the black mush in the relevant area.
Remove the gray wall of the potting module on the small side of the capacitor, (gray wall can be glued on again)
Cover the complete circuit board outside the Doghouse. thigt, to protect it from dirtit.
With an 12V craft drill, with a 2 mm grinding drill, I would only expose the PINs on the small sides.
The PINs, are exactly in the middle of the small sides and directly behind the hard plastic housing.
Then, undercut the bottom of the capacitor, along its entire length with a fine, long cutter knife to solve it from the circuit board.
That's it.
All processes are documented with many meaningful photos.
I would now replace the defective parts, this week. The tension increases.
Important:
Do any of you have any tips on what else I should check?
Thank`s to kiev and others for the great job, you do.
Congratulations! to philsuth, you really deserved the success.
I only read part of the thread, so I only know part of the great people here.
With sunny greetings from Germany
siggs
(The nickname, that the gringos gave to me, instead of the unpronounceable Krautname Siegfried) :lol:
PS:
Thanks to the admin for the happy end, of this Registration. What is the problem ?
So far, I never had a problem with our E-mail.
I just registered.
To the point: Defective OBC on I_MIEV Bj. 2011.
OBC 02/08/2011, with external EMI filter attached on Top of Case.
Visible defect on the blue capacitor C122 (one of two) which lies next to the relay center in the cast module on the lower board.
see link:
Mitsubishi i-MiEV On Board Charger (OBC) repair.
MIEV_OBC repair newer year of construction (Bj. 2011.12.25)
Here the module below with the power semiconductors has been removed to
replace the blue C121 and the green C122 with 2 new blue ones
https://www.youtube.com/watch?v=WVyXuSkn4jc
My circuit board has been removed, the black mush removed in the relevant area.
I checked the defective capacitor and carefully crumbled it to get its PINs free and save them in full length.
Reason: solder the new one to these pins to avoid soldering from below, because in addition,
the module below with the power semiconductors would have to be removed (56 solder points ! )
If I look at the soldering pattern of the 2 free PINs, then I am relatively sure, that the holes are vias (plated through)
So unsolder the pins and solder in the new component from above?
The distance between the capacitor and the circuit board would be 2 mm longer.
(A rough calculation with an inductance of around 1.2 nH per millimeter of cable length can be calculated. (Thanks to wikipedia)
So that shouldn't be a problem?
User Simon seems to have done it because of the soldered image.
Has replaced the 2 blue capacitors with 2 orange ones.
link
http://myimiev.com/forum/viewtopic.php?t=4079
Down the page to the photo series and then to the photo with the heading:
Beautiful Snubber Repair Job by Simon
(on the photo above, with the heading: Bottom Board "DogHouse" - the fenced-in potted area,
you can also see how my "DogHouse" looked like when it was still OK)
Although the second blue capacitor C121 is optically OK, I would also replace it.
2kV, 1000pF 1000pF = 1 nF ceramic capacitor
I documented all the steps with photos, which I will send on at the end of the repair. to:
https://www.goingelectric.de/forum/ and http://myimiev.com/forum/.
After reading a lot in https://www.goingelectric.de/forum/ and http://myimiev.com/forum/.
I examined other vulnerable components for possible defects:
The 2 ceramic resistors component R105 (the larger one) and component R106 (the smaller one)
Component R105 (the larger one) P10K TAM (manufacturer TAMURA) 4.7 Ohm J, 157 ° C.
Looks like new.
Measurement infinite Ohm = interruption!
I stripped the component carefully forensically to see internal defects.
P10K TAM (manufacturer TAMURA) 4.7 Ohm J, 157 ° C 105 (meaning of 105 unknown).
The 157 ° C relates to the trigger temperature of the integrated thermal fuse.
Although this has a declared current carrying capacity of 15A at 250V, it is pure
non-resetting temperature fuse. This is defective.
The wirewound resistor is OK.
Component R106 (the smaller one) 7K TAM (manufacturer TAMURA) 4.7 Ohm J, 105 (meaning of 105 unknown).
Optically OK, only 1 slightly brownish spot.
Measurement infinite Ohm = interruption!
Component carefully forensically stripped to see internal defects.
The wirewound resistor has partly burned out.
Wire diameter both approx. 0.40 mm
So both, probably 5 W.
I measured the 2 ceramic resistors in the installed state, through the narrow gap to the waffle plate module with the power semiconductors.
Used the following kitchen tools from my wife, as measuring tips:
2 x beef roulade skewers made of stainless steel Dm = 1.5 mm L = 100 mm, super-pointed. You can get any PIN.
Component K ??
Relay F + T (manufacturer) type: K1AK005W-KW 5Vdc 16A, 277, VAC RES.
Contact symbol for 1 contact NO, 16A 250VAC.
1040L2 China with VDE mark
Measurement of relay contact, resistance infinite = OK. Relay contact not glued.
Measured at the end of the series connection R105 - R106. Between # 11 and # 14 on user kiev`s circuit diagram.
Measurement relay K ?? Relay coil 5V, 59 Ohm, 85 mA and 0.43 W, energized with source 5V sc 300 mA
(for safety reasons source with small sc)
Energized at the free-wheeling diode D301, positive pole at the diode bar.
This freewheeling diode is missing on user kiev`s circuit diagram.
Relay clicks and contact closes with 0 ohms. Relay OK.
Although the MP capacitor C106, 2.2 µF, 310 VAC, optically is TOP, I also change it to be on the safe side. .
Removal:
The black mush, removed in the relevant area.
I removed the gray wall of the potting module on the small side of the capacitor, (gray wall can be glued on again)
The capacitor, sawn, blown, tattered. Horrific work. :mrgreen:
With an 12V craft drill, with a 2 mm grinding drill, I exposed the pins on the stripped floor.
Undercut the bottom of the capacitor, along its entire length with a fine, long cutter knife to solve it from the circuit board.
Get the 2 PINs in full length L = 14mm.
TIP: It's a lot easier.
Remove the black mush in the relevant area.
Remove the gray wall of the potting module on the small side of the capacitor, (gray wall can be glued on again)
Cover the complete circuit board outside the Doghouse. thigt, to protect it from dirtit.
With an 12V craft drill, with a 2 mm grinding drill, I would only expose the PINs on the small sides.
The PINs, are exactly in the middle of the small sides and directly behind the hard plastic housing.
Then, undercut the bottom of the capacitor, along its entire length with a fine, long cutter knife to solve it from the circuit board.
That's it.
All processes are documented with many meaningful photos.
I would now replace the defective parts, this week. The tension increases.
Important:
Do any of you have any tips on what else I should check?
Thank`s to kiev and others for the great job, you do.
Congratulations! to philsuth, you really deserved the success.
I only read part of the thread, so I only know part of the great people here.
With sunny greetings from Germany
siggs
(The nickname, that the gringos gave to me, instead of the unpronounceable Krautname Siegfried) :lol:
PS:
Thanks to the admin for the happy end, of this Registration. What is the problem ?
So far, I never had a problem with our E-mail.
Great work there Siggs, glad it was a success. Thanks for sharing.
I checked again control board - I don't see anything wrong with it. I soldered wires with connector to resistors places and I connected resistors to this connector, so if resistor died I will take it out from connector, resolder connector to new resistor and connect it back. Also I used 8 5w 20om resistors to build up 2 40w 5om resistors. I don't know if it would help. Last time I used 10w 4.7 om resistors and it didn't help. Also I soldered wires with connectors to duplicate 5v line from control board to relay. Will see if it would work or not.
The main controller chip, IC701, looks to have some surface distress? Maybe damage or just marked up thru the conformal coating?
