charliejuliett
Posts: 13
Joined: Fri Jun 10, 2016 1:01 pm

Eliminating Mitsu's Onboard Charger/DC-DC Converter

Tue Aug 28, 2018 10:13 am

My 2012 imiev recently had its OBC fail in the middle of a charge cycle. (35K miles) The aux battery was in good condition and the car was charging in a cool garage. I live far from a Mitsubishi dealer (Upper Peninsula of Michigan) so I decided to try and fix the problem myself. The car was back on the road in 9 days.

Here is what I did:

1) Removed the entire assembly that houses OBC. Covered all open connectors with shrink wrap covers.
2) Rerouted the cooling hoses to account for the dcdc converter charger box being gone.
3) Replaced fuse in the inverter box with a 400vdc 4amp fuse
4) Used the carsoft i909 to clear the error codes on the ev ecu.
5) Plasma cut an 1/8 aluminum plate to mount the coolant tank and a brand new HLG-600H-15A from Meanwell. This power supply is meant to drive LED lights, it has adjustable voltage and current pots built in with a remote and 5V output line, and has a 431 VDC input limit.
6) Wired up the high voltage DC from the inverter box to the input of the mean well power supply, put an arduino micro controller on the 5v line to trigger the remote line a second after the supply gets input voltage. (otherwise the car will trip an error code during start up) The output of the power supply is set to 14 volts (after the diode) and routed though a high power diode which is affixed to the aluminum plate with thermal paste.
7) The expensive part (but worthwhile, I can charge the miev at 7.2 kw now) I bought a chademo charger from evseadapters.com, I use that since I no longer have an on board charger. Takes about an hour to go from 20% to 80%.

A couple notes: with the high beams on and the hvac fan on high, when the brake booster pump kicks on I can draw more current than the power supply can manage, so my voltage will dip into the 12.7 range for a few seconds. So far it has not been an issue, I just use a voltmeter in the 12v power jack to keep an eye on things. The red battery indicator light will stay lit on the dash since the car thinks it has no DC DC converter- I took apart the dash and put electrical tape over the back side of the overlay.


3700$ total into this endeavor, but I got the car 4 years ago for 5900 and its been a real treat to drive so it was not hard to justify. Link to the charger:
https://www.evseadapters.com/collection ... ck-charger

Here are some pictures of the fix and the fancy new charger:
https://drive.google.com/drive/folders/ ... sp=sharing


Response to some very good questions about this mod:

1) The setec charger takes the car to 80%, you need to restart the charger manually to charge to 95% (See comment 6)

2) Cell balancing does appear to be taking place, I have 4.10 volts across the board according to canion when I charge to 95%

3) I also bought the J1772 EVSE to nema 14-50 outlet from evseadapters.com to use at public charging stations, though I mainly charge at home. I can route the cables through the rear window so the charger stays inside the car if its rainy or snowing.

4) The meanwell power supply is completely sealed except for the access ports for the pots only have a rubber plug in them.

5) I thought about using the Elcon PFC2500 Charger, and at less than 800 bucks that would have been cheaper. I still think I would have gone this route if I had more time and skill.

6) The charger does cut off at 5 amps, or about 95% SOC. All cells appear to be balanced, will update if this is no longer the case in a few years.
Last edited by charliejuliett on Mon Sep 17, 2018 5:55 pm, edited 3 times in total.

jray3
Posts: 1575
Joined: Tue Dec 06, 2011 1:05 am
Location: Tacoma area, WA
Contact: Website

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

Tue Aug 28, 2018 10:30 am

charliejuliett wrote: I live far from any Mitsubishi dealer (Upper Peninsula of Michigan) so I decided to try and fix the problem myself. The car was back on the road in 9 days.
Hot Damn- you fixed the problem for less than a dealer would've charged, and successfully doubled charging speed while retaining CHAdeMO ability! The main downside I see for that Meanwell power supply will be salty water intrusion in your environment. Could be a good time to add a belly pan.

Thank you CJ- this is the sort of hacking that will be of increasing importance to keep these cars on the road in future years!
2012 i-SE "MR BEAN" 94,000 miles
2000 Mazda Miata EV, 78 kW, 17 kWh
1983 Grumman Kurbwatt EV,170 kW, 32 kWh
1983 Mazda RX-7 EV 43 kW 10 kWh
1971 "Karmann Eclectric" EV 240 kW 19 kWh
1965 Karmann Ghia Cabriolet

JoeS
Site Moderator
Posts: 3574
Joined: Thu Dec 15, 2011 5:47 am
Location: Los Altos Hills, California

Eliminating Mitsu's Onboard Charger/DC-DC

Tue Aug 28, 2018 10:46 am

Charliejuliett, thank you!! I'm still digesting the details of your mod, but this is exactly what I had in mind when the charger/dc-dc problems started getting serious. The bonus is that you have a higher-power charging capability that is also portable. As jray3 pointed out - at less than the cost of a replacement Mitsubishi part!

I created a new topic and moved your post in here so as not to dilute the excellent thread that kiev and his astute team have in pursuing and repairing the i-MiEV's onboard charger/dc-dc.

Edit: Now that my excitement has died down, I have a number of questions -

1. When using public J1772 EVSE you would simply use an adapter such as one from http://www.tucsonev.com/? Oh, I see that evseadapters.com has one also.

2. Does the i-MiEV shut off at 80% or can you force it past that?

3. Does cell balancing take place?

Once again, the CHAdeMO charger that you are using is -

https://www.evseadapters.com/collections/ev-chargers-and-evses/products/portable-chademo-ccs-combo-dc-quick-charger

Yet another edit: More questions -

4. I recall that one of the problems with the way CHAdeMO was implemented on the i-MiEV (unlike the Leaf) is that CHAdeMO supposedly shuts off below 5A dc input current. Have you seen this?

5. Had you considered a conventional EV charger?

One more Edit:

Here are the specifications for the HLG-600H-15A power supply -

https://www.meanwell.com/Upload/PDF/HLG-600H/HLG-600H-SPEC.PDF

It is rated for 36A and the "A" part number suffix means the output voltage is adjustable
EVs: 2 Wht/Blu SE Prem., '13 Tesla MS85, 3 156v CorbinSparrows (2 Li-ion), 24v EcoScoot(LiFePO4)
EV Conv: 156v '86 Ram PU, 144v '65 Saab 96
Hybrids: 48v1kW bike
ICE: '88 Isuzu Trooper. Mothballed: '67 Saab (orig.owner), '76 MBZ L206D RHD RV

JoeS
Site Moderator
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Joined: Thu Dec 15, 2011 5:47 am
Location: Los Altos Hills, California

Re: Eliminating Mitsu's Onboard Charger/DC-DC Converter

Wed Aug 29, 2018 5:43 am

NOTE: I just noticed that charliejuliett edited his original post and answered our questions there. My bad in doing those edits first, as we should keep these threads as ongoing conversations instead of going back and changing our posts (other than to correct errors that we should subsequently also note).
EVs: 2 Wht/Blu SE Prem., '13 Tesla MS85, 3 156v CorbinSparrows (2 Li-ion), 24v EcoScoot(LiFePO4)
EV Conv: 156v '86 Ram PU, 144v '65 Saab 96
Hybrids: 48v1kW bike
ICE: '88 Isuzu Trooper. Mothballed: '67 Saab (orig.owner), '76 MBZ L206D RHD RV

charliejuliett
Posts: 13
Joined: Fri Jun 10, 2016 1:01 pm

Re: Eliminating Mitsu's Onboard Charger/DC-DC Converter

Wed Aug 29, 2018 8:14 am

It seems my forum etiquette is lacking by going back and editing my original post without notice, I will do my best to conform and follow the rules from now on. :oops: I have been a longtime lurker on this site and a big thanks to those who post- there is tons of good information. I credit finding the 2 inch hitch and gas heater add-ons to the site, and they make the car a whole lot more useful.

I wanted to try and fix the charger on my car like others on this site are doing, but I realized pretty quickly that it would be well outside my comfort zone. Its a shame these things fail as early as they do and I really wish mitsu would send out a recall as the failure rate seems high.

So if you don't have a degree in electrical engineering- my caveman/brute force approach may be worth considering. I know the 36 amp output is nowhere near the original 90 amp unit its replacing, but it is possible to put these things in parallel if you find your DC demands are too high, but so far so good with just one. A benefit I forgot to add, the car lost about 30 lbs! I should note that it gains it all back and more if the setec charger is in the back.

CJ

JoeS
Site Moderator
Posts: 3574
Joined: Thu Dec 15, 2011 5:47 am
Location: Los Altos Hills, California

Re: Eliminating Mitsu's Onboard Charger/DC-DC Converter

Wed Aug 29, 2018 9:22 am

charliejuliett, no worries about the forum etiquette - I've been a worse transgressor in the past. Glad I found your post update by accident.

1. The 36A output should be fine for most applications and I might add not to run more than one window motor at a time.

2. I'm interested in some details of your Arduino time delay, as I haven't dabbled in that world.
EVs: 2 Wht/Blu SE Prem., '13 Tesla MS85, 3 156v CorbinSparrows (2 Li-ion), 24v EcoScoot(LiFePO4)
EV Conv: 156v '86 Ram PU, 144v '65 Saab 96
Hybrids: 48v1kW bike
ICE: '88 Isuzu Trooper. Mothballed: '67 Saab (orig.owner), '76 MBZ L206D RHD RV

coulomb
Posts: 106
Joined: Sun Jun 10, 2018 8:32 pm
Location: Brisbane, Australia

Re: Eliminating Mitsu's Onboard Charger/DC-DC Converter

Wed Aug 29, 2018 6:00 pm

This is a wonderful initiative. My only concern is that you might need some protection against excessive current in the input stage of the Meanwell, due to rapid pack voltage changes. For example see this:

http://www.evric.kestar.com.au/recommend.htm#DCDCDiode

I hope that your old charger can be used as parts to repair other people's chargers, and/or help reverse engineer them for repair. I think your solution, elegant as it is, won't be ideal for everyone.

charliejuliett
Posts: 13
Joined: Fri Jun 10, 2016 1:01 pm

Re: Eliminating Mitsu's Onboard Charger/DC-DC Converter

Fri Aug 31, 2018 5:56 am

Finally put together a wiring diagram of how to connect the off the shelf dc dc converter, which I should mention is less than 200$. As coulomb mentioned above, this solution is not for everyone, but it is quick if you have only one car to rely on as I did. The arduino code is a simple variation of the "blink" example, about as simple as it gets:

void setup() {
// initialize digital pin 13 as an output.
pinMode(13, OUTPUT);
digitalWrite(13, LOW);
}

void loop() {
delay(1000);
digitalWrite(13, HIGH);
}

I hope to someday find a imiev with a busted charger/dcdc converter for cheap and use this fix and my new 7kw charger to give it a second lease on life!

A link to the wiring diagram here:
https://drive.google.com/drive/folders/ ... sp=sharing

jray3
Posts: 1575
Joined: Tue Dec 06, 2011 1:05 am
Location: Tacoma area, WA
Contact: Website

Re: Eliminating Mitsu's Onboard Charger/DC-DC Converter

Fri Aug 31, 2018 10:59 am

charliejuliett wrote:Finally put together a wiring diagram of how to connect the off the shelf dc dc converter,

That diagram's a beaut! What program did you use to draw it? I've gotta put down the crayons sooner or later...
2012 i-SE "MR BEAN" 94,000 miles
2000 Mazda Miata EV, 78 kW, 17 kWh
1983 Grumman Kurbwatt EV,170 kW, 32 kWh
1983 Mazda RX-7 EV 43 kW 10 kWh
1971 "Karmann Eclectric" EV 240 kW 19 kWh
1965 Karmann Ghia Cabriolet

charliejuliett
Posts: 13
Joined: Fri Jun 10, 2016 1:01 pm

Re: Eliminating Mitsu's Onboard Charger/DC-DC Converter

Fri Aug 31, 2018 11:42 am

Some real top notch engineering grade tools... MS word with some help from MS paint! :lol:

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