my Miev will not charge

[redcane]

To me, it sounds like some other new fault has been introduced. [...] I think to go farther, you really need access to a MUT III, or get a dealer to run a scan on your car to see what the new fault actually is before you can go forward.

My carsoft i909 (MUT alternative) turned up yesterday, and it read an active P1A15 error code. So that gives us an idea of where the issue lies. It is indeed a new error code. The service manual suggests to check wiring harnesses and the 280A fuse in the battery pack. It also suggests a CAN bus test, which I'm not sure if I can perform with an i909. My plan is to read through anything related to the diagnostic steps in the service manual, and see what I can figure out. I don't really want to go back to the dealer to pay to get codes read off it, plus at the moment it would need to get towed there.

[kiev]

Swapping the EV-ECU did not fix the problem. Not sure what to do next.

Sorry to hear Mike. So with the EVECU swap, your car would start and go to READY, but it won't charge. And this is on the second OBC unit that replaced the original? This is looking like connectors or wiring harness issue, or possibly the low voltage power supply to the OBC (fuses and relays). Is there a DTC code coming up now in the EV-ECU, and what is the number code coming up from within the OBC? These will pinpoint the source of the issue.

[mikedufty]

They haven't been all that communicative about the technical side. I don't even know if it is still not just charging or doesn't drive at all now. Will try to find out more.

[skylogger]

REDCANE: If your fault is the fuses inside the battery pack, here is some info:
There are four fuses inside the main battery pack, that can be accessed/replaced, without having to remove the battery pack from the car.
There is a plastic cover, that covers the whole under belly of the car/battery pack, that is held on by a bunch of 10mm screws, but there is also two screws that have a weird plastic cap over them, that I had to break off, then has a non standard bolt head (not hex, not star) but I was able to jam a flat blade screw driver into them and remove them. once this plastic cover is removed, you will see two small door plates one on left and one on right. Behind these plate covers are the fuses.

[redcane]

REDCANE: If your fault is the fuses inside the battery pack, here is some info [...] Behind these plate covers are the fuses.

I appreciate the information on getting to the fuses. It seems like the fuses are near the main connections to the pack (also need checking as part of the P1A15 diagnoses procedure from the service manual).



I don't think it is the main drive fuse itself - 280A 300V is a lot of power to not notice the smoke come out somewhere. However I do want to check why the contactors aren't actuating. So we will likely want to check if we can apply voltage to the contactors and operate them, along with checking if there is voltage to them from the ECU. I'm not sure if the P1A15 trouble code is a symptom of the contactors not operating, or the cause of them not operating. I'm hoping the contactors can be physically accessed near the fuses.

[kiev]

Was this the car that had the service plug removed? Has it ever worked since the plug was re-installed?

Was it installed properly? The i909 can read the status of the service plug switch.

Can the i909 read your pack voltage with key to ACC or ON?

Is the Aux battery new or fresh? a worn out aux can prevent READY.

Does the car have DCQC Chademo port? It is possible to use the DCQC relay next to the EV-ECU to turn on the DCQC contactor and read the battery voltage at the fat terminal sockets.

Maybe the big pack fuse has blown, but then you have to wonder how and why did it blow? Did something short out in the MCU, etc...

[coulomb]

A worn out aux can prevent READY.

If it's been sitting idle in the workshop for months, even a new auxiliary battery could die, or at least require a good long charge.

That would be worth checking for sure.

[redcane]

This is the car that had the service plug removed.

After replacing the service plug, the contactors chattered the first two attempts to start it, and haven't been heard from since.

The i909 showed a stored trouble code for the service plug (P0A0A). The code isn't listed as active. I'm unable to clear codes from the EV-ECU, which I guess is due to the active P1A15 code. I've been able to clear codes from other ECUs.

The i909 can get readings from all the cell monitoring units. We can also get cell data from canion. I didn't notice a specific pack voltage read out. The i909 only connects to the ECUs when the car is on. Don't seem to be able to communicate with anything when car is in in ACC, but I really only tried the EV-ECU.

The aux battery was replaced about 6 weeks before the charrger failed. It's been on a battery charger on and off since. We've been doing some of the testing with a 10A lab supply connected and set to around 13.4V to rule out low auxiliary voltage. I suspect the long drive to the dealer without a functioning DC-DC will have damaged the battery, so I'll likely replace it if we get it back on the road.

Trying the quick charge relay and chademo port is a great idea. I might try that first this weekend, before the P1A15 service manual procedure.

[kiev]

i've never heard of anyone testing this, but if the HV fuse were blown, would the fuel gauge still show the bar lines for the battery pack voltage/SOC when the key is turned to ON?

One interesting observation you made was that the contactors were chattering and then never heard from again. So could the contact points be damaged and causing an open circuit (or is it the fuse)?

[redcane]

Fuel gauge is still displaying 4 bars. I think it is based on the BMS reading from the cell monitoring units, rather then from reading the overall pack voltage. It's definitely not taking a reading from outside the contractors. I should have noted what the fuel gauge did with the service plug removed.