Matheos
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Joined: Tue Jun 16, 2020 5:18 am
Location: Greece
Contact: YouTube

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

Wed Apr 21, 2021 10:43 pm

Hello again,
I have a question When the dealer says we can t communicate with OBC, does that mean the Upper board has fail?
And What is the surface mount element X501 on the top upper board near the high voltage section?

coulomb
Posts: 273
Joined: Sun Jun 10, 2018 8:32 pm
Location: Brisbane, Australia

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

Thu Apr 22, 2021 4:28 am

Matheos wrote: What is the surface mount element X501 on the top upper board near the high voltage section?

My guess is that it's the crystal for the processor on the other side of the board (IC701).

Sandrosan
Posts: 31
Joined: Tue Sep 24, 2019 2:43 am
Location: Milan, Italy

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

Thu Apr 22, 2021 4:35 am

@ Kiev,
thanks very much for the precious additional edit of your previous message that I just noted now.
This morning I removed the external power supply at 5 V and the transistor driver and fix back all in original condition.

Then I traced the circuit and make the draft in this link: https://we.tl/t-weFrPIjrum

Pls check if it correct.

Then I connected my PQA (logger) for monitoring the + 5V (on C705) that supplies the coil and the voltage on the collector of the TR301 together with the charging current.
Unfortunately the main battery was almost full (and there are some weak cells too) and then the charge current was reducing, a not good testing process! In fact the + 5V remanis stable and the voltage on the collector of TR301 too (close to 0 V apart the starting time). So I could not see any voltage fluctuation.

Now I have to discharge the main battery (using heating system it will take some 2 hrs I have noted, but I want to be there in case something goes wrong...).

On the other hand I fully agree on your sentence " Since you swapped the board and are getting the same behavior, then it is likely some issue with the 12V supply circuit external to the OBC (EV-ECU, fuse, OBC relay, loose terminal in some connector?...)".

But first I have to discharge the main battery, charge at full power (14A), hoping the voltage anomaly will appear again and ask the help of a friend of mine.
However I cannot do this today I hope in the next days.
Surely I will keep informed , hoping this will be of help for someone else.

Thanks

PS (Edit) I am wondering if the DC supply voltage circuits in the main board (IC317, IC702 etc and relative components) are involved on making the + 5V ? Or such part of DC supply voltage circuits are supplied by that +5V? Unfortunately such components are on the lower part of the main board that is not accessible without disassambling all the main board (action that I have never done till now and I am afraid of doing it).
Last edited by Sandrosan on Thu Apr 22, 2021 6:24 am, edited 1 time in total.

Matheos
Posts: 22
Joined: Tue Jun 16, 2020 5:18 am
Location: Greece
Contact: YouTube

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

Thu Apr 22, 2021 5:22 am

coulomb wrote:
Matheos wrote: What is the surface mount element X501 on the top upper board near the high voltage section?

My guess is that it's the crystal for the processor on the other side of the board (IC701).


Yes, I think you Have right! So what does the dealer mean by telling me he can not communicate with the OBC ?

Matheos
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Joined: Tue Jun 16, 2020 5:18 am
Location: Greece
Contact: YouTube

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

Sun Apr 25, 2021 11:15 pm

?

Sandrosan
Posts: 31
Joined: Tue Sep 24, 2019 2:43 am
Location: Milan, Italy

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

Mon Apr 26, 2021 5:46 am

Matheos,
I have learned that many dealers do not know too much, or almost nothing about EV car.... So I would not take too much into consideration such sentence.

Sandrosan
Posts: 31
Joined: Tue Sep 24, 2019 2:43 am
Location: Milan, Italy

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

Mon Apr 26, 2021 6:07 am

Hello to all,

This morning I have discharded the main battery and started the charging process with the max current, so 14A at 230V. Monitoring over time the 12V on pin 12 of CN101 connector , the 5V on C703 and the VCE of the Tr301.
The 12V is 14.2 V while charging.
The 5 V is 5.13V
The VCE is 0.065V approx. (so it is correctely saturated)

All of above voltages without any particular variation / fluctation! Even during the 20 mins pause at zero current (for balacing the celles I guess).

I have not touched anything in paricular from this test and the previous tests when the fluctuation occurs, so the problem is not showing anymore, very unfortunately.

While charging, I tried to move connectors, cables, flat cable, fuse box and 12V batt clips, but no fluctuation anymore....

Now there are 3 bars left to full battery, and no fluctuation.

To find out the problem when there is not the problem is hard :D
I need more tests and time.
If anyone has any extra advise, they will be welcome. Tks.

kiev
Posts: 1459
Joined: Sun May 03, 2015 7:15 am
Location: The Heart o' Dixie
Contact: Website

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

Mon Apr 26, 2021 7:06 am

The link did not show me the schematic, so i could not review it. Maybe you can post it as an image?

It sounds like your test was good but the problem did not occur. Was there anything different--temperature, charge or change the 12V aux battery, etc? An intermittent problem is the most difficult to solve.
kiev = kenny's innovative electric vehicle

Matheos
Posts: 22
Joined: Tue Jun 16, 2020 5:18 am
Location: Greece
Contact: YouTube

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

Mon Apr 26, 2021 1:02 pm

Another question : If the resistors are bad! Can you via a tool communicate with the OBC or not?

kiev
Posts: 1459
Joined: Sun May 03, 2015 7:15 am
Location: The Heart o' Dixie
Contact: Website

communication and OBC

Mon Apr 26, 2021 7:33 pm

If the big ceramic resistors have failed open, then no charging will occur and this will throw a DT Code. The code is stored in the EV-ECU, and it can only be retrieved by individuals and owners using aftermarket CAN buss tools such as an OBDII scantool or with a bluetooth or wifi dongle with one of the android/iOS applications.

The Mitsubishi i-MiEV, Citroen C-Zero and Peugeot iOn service departments all have different software packages and hardware to connect thru the OBCII port and communicate over the CAN buss with much more detail than the aftermarket solutions. Very few owners have been able to obtain these special tools but obviously they are highly desired and many fakes exist, so buyer beware.
kiev = kenny's innovative electric vehicle

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