electronpusher
Posts: 43
Joined: Sun Jun 25, 2017 3:11 am

Re: Troubleshooting and repair for On-board Charger (OBC), DC-DC Converter

Sat Oct 06, 2018 12:20 am

Ok, relay is good, used bench top power supply set to 4.5V@500mA (@coulomb saw your post after I did the test), heard it click. Woot!

Ok, so about to check the resistors.

electronpusher
Posts: 43
Joined: Sun Jun 25, 2017 3:11 am

Re: Troubleshooting and repair for On-board Charger (OBC), DC-DC Converter

Sat Oct 06, 2018 12:47 am

Alrighty, the resistors measured 9.7Ω, which I assume is correct (4.7Ω x 2 = 9.4Ω), so I assume that it good. Here is how I tested it.

Image

Full image: https://i.imgur.com/JdW1Kyh.jpg

We are about to re-assemble the OBC, top up the coolant and run the coolant pump cycle, and see what happens.

I am going to use a solar fuse (1000V 20A) for testing so that we do not have to wait 4 weeks for the OEM fuse if something goes awry.

Image

If all is good, I'll repot the doghouse and call it fixed.

electronpusher
Posts: 43
Joined: Sun Jun 25, 2017 3:11 am

Re: Troubleshooting and repair for On-board Charger (OBC), DC-DC Converter

Sat Oct 06, 2018 5:46 am

And for the good news, it looks like ours is fixed, woot!

So, what did we do.

  • Replaced the two caps with new through the hole caps, however these were soldered to the pins with the two pins that were soldered onto the upriser board used for each leg of the caps (i.e. each leg had the two pins). It was tricky, but it helped by having something between the waffle plate and the PCB to prevent the pins dropping through while de-soldering the board and soldering the new board. The upriser needs to be cut into four pieces to be removed.
  • Checked the relay using a bench-top power supply set to 4.5V@500mA (though coulomb suggested that 200mA would be better, and I agree, lower amps, less likely to blow the diode if you get the polarity wrong). We were extra careful to triple check that we had the polarity correct.
  • Checked the resistors (2 x 4.7Ω) and they measured 9.7Ω, I assume they are in series and therefore 9.7Ω was expected.
  • Added thick cables to the solar fuse holder and crimped on some connectors, used a 1000V 20A PV fuse, this was done for testing so that we did not blow up the OEM fuse which takes 4 weeks to arrive.
  • Reassembled the OBC, re-installed in the car.
  • Turned on the car, and all error lights were gone. YAY!
  • Toped up the coolant, and set to purge the system using the non-MUT-III method (since we do not have a MUT-III).
  • Set the system to purge air for 15 mins, coolant level remained the same.
  • Plugged in the 10A charger that came with our outlander (a proper EVSE charger, not the dodgy cable that came with the car).
  • Contacts clicked, and she started to charge.
  • Left to charge for 30mins, checking it regularly, and bingo, we got an extra bar.

So, we are going to let it go for a bit longer and keep an eye on it, but I think it is fixed.

Next up we will install the OEM fuse tomorrow, and repot the doghouse with neutral cure silicone, reseal the top lid of the OBC with silicone, and we are done.

A big big thank you to @coulomb, @kiev and @skylogger for all your help.

Edit: Now have two bars more than when we started the charge. :)
Edit 2: Now three bars up, now at 3/4 charge.

electronpusher
Posts: 43
Joined: Sun Jun 25, 2017 3:11 am

Re: Troubleshooting and repair for On-board Charger (OBC), DC-DC Converter

Sat Oct 06, 2018 5:58 pm

This morning we have put in the OEM fuse, and put it back on charge. Once we are at 100% SOC, we are going to disconnect the HV and 12V, open the OBC and repot the doghouse with neutral cure silicone.

skylogger
Posts: 66
Joined: Sun Dec 14, 2014 3:54 am

Re: Troubleshooting and repair for On-board Charger (OBC), DC-DC Converter

Sat Oct 06, 2018 10:11 pm

Great news Electronpusher
It is now looking like the majority of faults on these chargers are not major "power train" issues
I'm starting to think that either there is a power surge, or like KIEV says, a low 12v aux supply which puts the
chargers controller into a destructive state. If these were caused by power surge, then replacing the caps
and fuse are all that was required to get back running. If it was a 12v aux battery situation, It might be a
one off situation or the 12v battery may need to be replaced. There is a chicken or the egg situation, where if the 20 amp fuse
blows, the sudden load change may cause an inductive spike which feeds back and blows the 2x snubber caps.
There could also be the alternative theory that when the caps blow, they may first form a short, which can blow the fuse, but
then the short does not last long, as the caps end up becoming vaporised.
It's good to see that a few of these chargers are now getting fixed without any waffle semiconductor faults.
Seems that the waffle semiconductors are fairly robust.

electronpusher
Posts: 43
Joined: Sun Jun 25, 2017 3:11 am

Re: Troubleshooting and repair for On-board Charger (OBC), DC-DC Converter

Sun Oct 07, 2018 1:03 am

Yes it is great, we are happy. Charged to 100% today and allowed to complete balancing. Then disconnected the 12V and drive battery, left it for a few hours and then filled the hole in the doghouse with neutral cure silicon. Now we have to wait 72 hours for it to fully cure, before I put the top back on the OBC with a fresh silicone seal, reconnect the 12V and drive battery and she is good to go.

Mitsubishi Cost $5000AUD ($4500 for the OBC and additional costs for labour ~$500).

My cost: ~$150 ($22AUD parts [$20AUD OEM Fuse, $2AUD snubber caps], and other things like coolant, heat transfer compound, solar fuse).

A nice little saving, and I learnt a lot too. A big FU to Mitsubishi.

ChristopheFR
Posts: 9
Joined: Sat Aug 11, 2018 1:08 am

Re: Troubleshooting and repair for On-board Charger (OBC), DC-DC Converter

Sun Oct 07, 2018 10:38 am

Hello tout le monde,

Today I made new photos. On this one we can see the fused resistor. I did not see last time. We also see that the rubbery potting has boiled.
Image
Another problem, the 2x 2.2 microfarad capacitor seems inflated on both long sides.
Good news: the relay operates with a 4.5 volt battery, and I get 0 ohm when it is activated.
Questions:
1) should I change the capacitor as a precaution? I have not found a supplier in Europe for the Okaya capacitor, do you think that one is correct?
https://content.kemet.com/datasheets/KE ... X2_310.pdf
Same nominal voltage, same characteristics and same dimensions.

2) The reference of the fused resistor is hidden by the resistor P10k. Is it a 5k or a 7k Tamura? what reference to change it?
3) If the P10K resistor is also fused, what reference to change it?

ChristopheFR
Posts: 9
Joined: Sat Aug 11, 2018 1:08 am

Re: Troubleshooting and repair for On-board Charger (OBC), DC-DC Converter

Sun Oct 07, 2018 10:41 am

Electronpusher : I forgot in my last message : félicitation pour cette excellente nouvelle! :P

Phximiev
Posts: 1187
Joined: Thu Jan 15, 2015 7:25 pm
Location: Phoenix

Re: Troubleshooting and repair for On-board Charger (OBC), DC-DC Converter

Sun Oct 07, 2018 11:13 am

Great job! Now is that the same board that controls the charging rate? And if so, how can the charging rate be increased?

:idea:
2012 iMIEV ES
2014 Chevy Volt

kiev
Posts: 779
Joined: Sun May 03, 2015 7:15 am
Location: The Heart o' Dixie
Contact: Website

Re: Troubleshooting and repair for On-board Charger (OBC), DC-DC Converter

Sun Oct 07, 2018 1:14 pm

ChristopheFR wrote:.... On this one we can see the fused resistor. I did not see last time. We also see that the rubbery potting has boiled.
Questions:
1) should I change the capacitor as a precaution? I have not found a supplier in Europe for the Okaya capacitor, do you think that one is correct?
https://content.kemet.com/datasheets/KE ... X2_310.pdf
Same nominal voltage, same characteristics and same dimensions.
2) The reference of the fused resistor is hidden by the resistor P10k. Is it a 5k or a 7k Tamura? what reference to change it?
3) If the P10K resistor is also fused, what reference to change it?


Good work to catch the resistor and the safety (X2) cap.
1. yes change it while you are in there, the kemet should be a good substitute.
2. and 3. It is a 7K without the internal fuse, not sure about substitutes for these parts.

The Tam datasheets are linked in this post: viewtopic.php?f=23&t=4079&start=140#p37274

Even though the relay seems okay by your test, it doesn't prove that it wasn't damaged--i would bet that it has been damaged and should also be replaced, especially since so many other parts have damage, you may as well replace the relay as cheap insurance. In addition you need to determine what caused the power resistors to get overheated--were the relay contacts frosted over and not making good contact, or did something interrupt the 5V supply to the relay coil?

You will need to desolder the waffle plate to get access for the cap and resistors, and the relay. Unless you are quite skilled at this sort of work, then i would recommend that you find an electronics repair shop with a powerful vacuum desoldering gun to help you make these repairs--it is difficult to desolder the plate without the right equipment.

Considering the amount of work to remove the plate is also why i recommend to replace the relay--once you are in there it is easy to replace, and you don't want to have to repeat all this because of an unknown failure of the relay.
kiev = kenny's innovative electric vehicle

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