Charging stopped due to system malfunction

[asavage]

Kind of a dumb question I think. How do I remove the transparent plastic cover to access the HV terminals?

I used an o-ring pick tool (the right-angle variety: so useful). Pack of four for like $2 at HF.



In practice, I use only the right one, but I use it a lot.

Through the hold-down hole.

 

[Rakesh Suresh]

@asavage I have the rightmost tool, but I was worried about breaking it. I was able to pry it out now applying a bit more force

 

[hokiematt]

Kind of a dumb question I think. How do I remove the transparent plastic cover to access the HV terminals?

The plastic cover pulls straight out; there's a gasket around the perimeter to make it weather-resistant that also means a little force is required to remove it.

Note that there is an interlock pin molded into the clear cover (about a third of the way up from the bottom). Unless you insert something (non conductive) into the hole in the receptacle to close the switch inside the DC-DC assembly, the BMS will not turn on the contactors and you will get a 'Check EV System' fault displayed.

From your photo, it looks like there are interlock terminals on the other high voltage connectors as well (small terminals adjacent to the high voltage ones). As the interlock system is basically a bunch of closed jumpers in series, having any of these circuits open will keep the contactors from closing.

 

[asavage]

The connectors on the harness for the Cabin Heater, A/C Compressor, and Battery Heater all have jumpers molded into their KET connectors. Disconnect any one of them, and the HVIL (High Voltage InterLock) loop is broken, and the BMS disallows contactors closure.

Vlad recently posted a nice pic of the HVIL interlock on the DC-DC's input cover, over in the THC_d0013 thread.



More info on the HVIL system is linked from this post.

 

[alflash]

The connectors on the harness for the Cabin Heater, A/C Compressor, and Battery Heater all have jumpers molded into their KET connectors. Disconnect any one of them, and the HVIL (High Voltage InterLock) loop is broken, and the BMS disallows contactors closure.

Vlad recently posted a nice pic of the HVIL interlock on the DC-DC's input cover, over in the THC_d0013 thread.

View attachment 817

More info on the HVIL system is linked from this post.

+ To this Switch.
https://alflash.com.ua/2019/to_rav4ev/_hvil_switch.jpg

Checking the DC/DC Converter Compressor power supply voltage fuse
https://alflash.com.ua/2019/to_rav4ev/cond_fuse.jpg

+ photo of the one cause of cabin heater malfunction (burnt contact)
https://www.myrav4ev.com/threads/who-still-owns-a-rav4-ev.2572/page-3#post-30305

Another reason for a blown fuse is a broken transistor.
https://alflash.com.ua/2019/to_rav4ev/cabin_heater3.jpg

And this is a test of the cause of the transistor failure.
https://alflash.com.ua/2019/to_rav4ev/cabin_heater1.jpg
Unfortunately, low-skilled technicians only change the transistor, but do not check the resistance of the heating elements.
https://alflash.com.ua/2019/to_rav4ev/cabin_heater1.jpg

The photo shows the check of a serviceable element.

 

[Arlin]

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.

Hmm I have fuses coming. But I parked in front of work today for 10min to save time and it was at an EV charger so I plugged in... And I have not changed the fuses yet but it started charging with L2 (30a 208Vac).... I wonder if a contactor welded? And now its freed up? What else would cause this. I measured with a DMM and when it was not charging last week it failed that test.... I will check again today.

 

[asavage]

Arlin, you can't charge with "one good fuse" in the OBC. Whether you're charging with 120v or 240v (or 277v), the same two wires and fuses are in use. If one fuse fails, it's an incomplete path and the OBC will not charge.

Do you have a thread going on your issue? If so, post a screenshot from TPD on your thread (don't post it here, Rakesh has enough going on here).