Posts: 2
Joined: Sun Jun 09, 2019 6:49 pm
Location: Perth, Australia

Heat Damaged Charger Plug

Wed Jun 12, 2019 3:18 am

Hi all. First post here and keen for some iMiev advice.

I'm from Perth, Australia and test-drove a 2012 iMiev for sale at a local car dealership today.

https://www.carsales.com.au/cars/detail ... 4455/?Cr=0

I've previously spent a few hours reading through the contents of a few posts here to better understand some of the iMiev issues I might be faced with.

The iMiev for sale has very low kilometres for its age (7200kms - 2012). That did have me very curious but was unanswered by the salesman.

More concerning is heat damage on the 15 Amp Level 2 car charger plug. My limited understanding is that the OBC can have a failure mode that causes high inrush current (Pre-charger circuit failure?). I read a couple of UWA chargers were damaged by a particular iMiev, but the same car would charge on higher capacity chargers.

I'm looking at the attached picture and presume that the charger has pulled much higher current than designed. One of the pins on the plug is so loose it seems it could fall off.

The vehicle has a 10 Amp plug and Level 1 charger (undamaged) and also a 15 Amp plug and Level 2 charger (pictured). I wasn't in a position to check the functionality of either.

Any feedback on what could cause this? I've read through the 38 pages of 'Troubleshooting and repair for On-board Charger, DC-DC Converter', so I think I'm across most of those components.


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Re: Heat Damaged Charger Plug

Wed Jun 12, 2019 7:28 am

Welcome to the forum! Sounds like you've found a very nice low miles (kms) car - Those are the best ones

The 'charger' is built into the car. What you're calling a charger is actually the EVSE (Electric Vehicle Supply Equipment) and a heat damaged plug on the EVSE has nothing to do with the condition of the charger in the car. The EVSE is nothing more than a 'smart' extension cord, used to connect the charger in the car to the AC mains in the house

Most times you see a melted plug on an EVSE it's due to an older, worn out socket in the house which causes a high resistance connection when you plug it in. EV's draw substantial current and for several hours, so even a slightly dirty connection at the wall can eventually result in an overheated connection - I'll bet the socket in the original owners house doesn't look much better than the plug in your photo. The EVSE regulates the amount of current sent to the car, so it wasn't caused by too much current for the charger, but obviously it was too much current for too long for the connection at the wall. You should be able to put a new plug on your EVSE and then make sure you use a new socket at your house to plug it into and you should not have that problem again

2012 iMiEV SE Premium, White
2012 iMiEV SE, White
2017 Chevy Volt Premier
2014 Ford Transit Connect XLT SWB wagon, 14,000 miles
1979 Honda CBX six into six

Posts: 2
Joined: Sun Jun 09, 2019 6:49 pm
Location: Perth, Australia

Re: Heat Damaged Charger Plug

Wed Jun 12, 2019 4:21 pm

Hi Don. Thanks for the quick reply!

Yes, my use of terminology for this new (for me) market needs improving. :oops:

My next step is to take it to a dedicated EV mechanic for an appraisal of the battery cells and functionality of both EVSE. I'd like to ensure that with the long storage time this vehicle must have experienced, there hasn't been any issues develop.

Any other useful tips when looking over a potential new (2nd-hand) iMiev?

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Re: Heat Damaged Charger Plug

Thu Jun 13, 2019 5:26 am

Howdy Icarus,

i assume that the dealer would let you test drive the car. When you turn on the key the dashboard will come alive and you can read the gauges. So check the "fuel" gauge to see how full it is and count how many bars are showing, Full is 16 bars. Half is 8 bars.

You probably won't know when or how it was last driven, or charged, or calibration charged, but at least you can look at the odometer data with the push-button display. Cycle thru the readings until you get to "RR" which is the range remaining. Note the value and do some quick math, a typical normal RR reading will be about 4 miles or 6.5 km per fuel bar. This is a quick and simple check on the overall health of the pack and the car in general, if you are close to this then the car is worthy, if not then questionable.

p.s. i agree totally with Don's post and think it would be an easy repair to the plug, maybe you can use that "damage" to get the price down a bit.
kiev = kenny's innovative electric vehicle

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Joined: Fri May 13, 2016 12:58 am
Location: North London suburbs, UK

Re: Heat Damaged Charger Plug

Fri Jun 14, 2019 2:51 pm

Hi and welcome to the forum.

As others have said... nothing to do with the car's on board charger or the EVSE charging lead (which would protect the car from any damage anyway).

I've had this happen on my own 2012 IMIEV in the UK, also running on 230-240V domestic. As has been said, if you draw too much current from a power outlet in the wall for extended periods, and 3Kw for several hours is a lot for typical domestic wiring (especially if it's on a spur, rather than a ring main - hopefully the language complies here), then that can quite easily happen.

It happened to me when I had no option but to charge from fairly long extension lead, and it melted the Mitsubishi supplied 3 pin British plug to the RCD protector, which tripped the circuit - but funnily enough, neither the RCD on the plug, nor the fuse in the plug went - it was the main breaker in the electrical box in the house. It was a hot day by UK standards (about 32 degrees last year).

The fix was just to remove the melted plug and replace it, and it's all working fine now (though I replaced it with a hard plastic one, rather than the soppy soft-touch rubber-type Mitsubishi had supplied - so get a good quality one).

I don't tend to use the Mitsubishi supplied charging cable, but rather my Level 2 wall charger and Type2-Type 1 lead,. Even though the charging rate is 3.3-3.6Kw vs 3 from the standard kit, the wall charger is wired directly to my home fuse box via a short cable with a 6 or 8mm cross sectional diameter, rather than 2.5mm from standard wall outlets - so it's far safer, and offers far lower resistance - better all round... never had any issues.

If you were really unlucky with a wall outlet melt, then I could envisage it damaging the wiring in the wall, which could be a significant pain, and potentially highly costly to fix... which is another reason I try not to charge off a standard domestic plug, especially if I need a full charge, and any length of extension lead.

Looks like you have found a nice low-mileage car, which should be fine, but do get the battery health checked out, as very hot weather and prolonged full charge state isn't good for the battery... and change the 12v battery as a precaution, unless you can verify it has been changed fairly recently.


2012 I-MIEV Keiko Silver 16K
2010 Insight ES-T 43K
2001 Accord Type-V (F23 manual)
2009 Hornet CB600F
2008 SH300

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