Charging stopped due to system malfunction

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Rakesh Suresh

Member
Joined
Sep 5, 2024
Messages
23
Hello,

After around 68K miles of trouble free operation looks like car is exhibiting a bunch of issues all of a sudden. Now it failing to charge with this error message. Here is the diagnostic details. Thanks to @asavage for the cable and guide on how to use TPD, getting the info was a breeze.

TPD report.png

dc-dc.png
Resistances at the J1772 pins are what described here. I presume that it is a faulty OBC

Background:
  • Since 2023, Check EV system has been on after it was left with a dead 12v battery for several months. I got annoyed with the 12V battery dying all the time. I had installed a 12V LiTime Lithium battery with battery monitoring. Drove it for about 1 year with the Check EV system on. Drove it for a year thinking it was only related to the dead 12V battery

Current problems
1. Not charging
2. Cabin heater not working
3. Battery coolant pump error code
4. Found moisture on speed sensor


Questions:
  1. I bought a Gen 1 OBC and 2 FWH-50B fuses. Could someone point me to how to program this? After replacing, can this be tested before I put everything back? Decided to fix the pump first per advice below
  2. A few months ago, it started showing much lower range, around the value it would show if the heater was on. Almost appeared as if it thought the heater was on while it was not. Then noticed cabin heater was not working. Looking at the screenshot above, it appears DC-DC is working fine? I guess I need to follow this?
  3. Any pointers on how to go about fixing the battery coolant pump 2 issue?
  4. Per advice from @asavage, I checked the speed sensor and there were a few droplets of condensate which appeared colorless. Is a coolant delete a sufficient fix or should the LDU be taken apart to remove the coolant?

Thanks in advance !
 
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Sorry, Ramesh, I stopped reading after the screenshot. Replace the water pump No. 2 that serves the OBC, and "Bob's your Aunt". The OBC is probably overheating due to lack of coolant flow. The water pumps are consumables and fail; they're relatively cheap, and relatively easy to replace. Search on "water pump" and find a previous thread on this, where I posted a diagram as to which pump is No. 2 (there are four of them).
 
I went through several posts about water pump replacement and I have a few more questions:
1. In the screenshot, the thermal controller shows 30% for battery pump 2. Does that mean pump 2 is running at 30%?
2. Is further diagnosis required or should I just proceed to replacing the RH pump?
3. I presumed diagnosis is necessary. To disconnect D6, is that accessible on the DC-DC convertor or do I need to get under the car?
 
1-2. Yes, Thermal Control ECU, receiving a feedback signal*, "knows" that the pump motor is running with a duty cycle of 30%, shown in your screenehot.​
*

3. Please explain what "disconnect D6" means and what does DC-DC Converter have to do with the codes in the screenshota?​

I suggest doing Clear THC DTCs

and recheck/read the codes/alerts again.
 
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@alflash I I was referring to "Disconnect connector D6 from the water pump with motor RH (for HV battery)." which is a part of troubleshooting steps in page 3 of the pdf you linked above.

Will clear the code and report back
 
Looks like the pump 2 error message went away after clearing the code but charger malfunction exists. The heater is also not working

tpd-after clearing.png
 
Looks like the pump 2 error message went away after clearing the code but charger malfunction exists. The heater is also not working
...
A great step in the right direction. We have already avoided a needless purchase and replacement of the pump. :)

Moving on.
Is it possible to check the fuse for the cabin heater?
The check is described in T-SB-0111-14 "HVAC - Heater Inoperative" (let me know if it is needed).

Perhaps this video will be interesting


I'm sure that it would be useful to see a table with the results of checking the resistance between the contacts of the charging port connector.
Such photo fixations are welcome.
https://alflash.com.ua/2019/to_rav4ev/resistor_check.jpg
resistor_check.jpg
 
...

I'm sure that it would be useful to see a table with the results of checking the resistance between the contacts of the charging port connector.
Such photo fixations are welcome.
https://alflash.com.ua/2019/to_rav4ev/resistor_check.jpg
resistor_check.jpg
Thank you for such inattention to my request.
Dear Sir, I do not know (I hope I will survive this :) ) the results of checking the resistance between contacts 3 and 4, as well as between contacts 3 and 5 of this connector with the negative terminal of the 12V battery disconnected.
https://alflash.com.ua/2019/to_rav4ev/port.png
port.png


Sorry for bothering you with my request.
Have a successful and effective installation of the newly purchased pump.

For reference only.
https://alflash.com.ua/2019/to_rav4ev/078a.png
078a.png

and https://www.myrav4ev.com/threads/my...a-rav4-ev-not-charging-fuse-blown-issue.2530/

BR,
 
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@alflash I agree, I didn't pay attention to the pins you were referring to regarding the resistance check and thought they were the same as what was mentioned elsewhere on other threads. Moving forward, I will be less impatient and carefully read the instructions. I apologize for any frustration this may have caused and appreciate your help on this. Hope you can excuse me this time :)

To clarify, I had ordered the pump right after I saw the comment from asavage "Replace the water pump No. 2", before you commented.

Will do the resistance check and report back shortly.
 
I hope I have followed the instructions correctly this time.

Prep:
20240911_132800.jpg


Resistances:

Pin 3 and pin 4 - 2.467 Kohm
20240911_133258.jpg

Pin 3 and Pin 5 - 80.1 Kohm
20240911_133435.jpg
 
Mine did this today as well. One of the pins to the GND is open and the other measures 0 ohms I got lucky and found the 120Vac charger worked as it must be on the good pin lol Not sure if I should worry about the 0ohm reading or if it will go back up with the blown fuse replaced.
 
@alflash Then the next best hypothesis would be that the OBC is faulty, correct?

> Is it possible to check the fuse for the cabin heater

This would need checking the continuity between HV terminal and cabin heater terminal, correct?
 
@alflash Then the next best hypothesis would be that the OBC is faulty, correct?

> Is it possible to check the fuse for the cabin heater

This would need checking the continuity between HV terminal and cabin heater terminal, correct?
Yes, as show indescription of checking this fuse in T-SB-0111-14.
And in compliance with electrical safety regulations.
 
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Mine did this today as well. One of the pins to the GND is open and the other measures 0 ohms I got lucky and found the 120Vac charger worked as it must be on the good pin lol Not sure if I should worry about the 0ohm reading or if it will go back up with the blown fuse replaced.
Please illustrate between which contacts of the charging port connector the resistance is zero and please show a photo with the result of this measurement
 
There's a link to the "how to test the cabin heater and its fuse in the DC-DC Converter" service bulletin somewhere in this post.

That is toward the end of a 16-page thread on the cabin heater issues, and if you don't want to read much else, read from this other post forward, plus that SB, and you should have much of the current state of the cabin heater's ills in mind, other than actually replacing the fuse process (for which, you'll have to read a lot of the earlier thread).
 
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