Not able to drive. P1A15 error.

[kiev]

We don't have the firmware so don't really know anything about how the car is controlled.

There is a note in the HV wiring diagram section of the FSM:

Do not remove the A/C cable from the main battery.

The Leaf and Tesla use an interlock loop in the HV connectors of the pack, just don't know if these cars do.

i would guess that the status of HV to the AC compressor is sent over the CAN buss to the EV-ECU, and that may be triggering the permanent fault that can't be cleared.
http://mmc-manuals.ru/manuals/i-miev/online/Service_Manual/img/55/AC902570AB00ENG.pdf

 

[boothegermanshepherd]

The days diagnosis carries on like this.....

Carried out the manufactures test steps relating to this fault code and the diagnosis now points to the inverter.........

I have taken the lid off and it looks brand spanking new in there with no smell

So when I remove it tomorrow what am I looking for when I strip it down?

Thanks again for everyones input

 

[kiev]

There is no need to remove it from the car, and if you do you won't be able to test it.

The control board is in the bottom plenum behind the bottom lid; the top plenum just has the big capacitor and the inverter FETs and current sensors. Never seen a failure up there, and it would be a different DTC.

Follow this link to the page with pictures and the discussion that follows of what to measure and check. There is a schematic on that page also. The hybrid board is shown and has been traced out but no schematic drawn up yet. The vendor will not sell the ISA215 board except to OEMs with large purchase orders. If you are handy with soldering then i would recommend to remove and replace all the components on the hybrid board. Due to the intermittent nature and thermal aspects of this code, i suspect the ceramic capacitors are a prime culprit. That is the only electronic part i know which can appear to "heal" itself.

http://myimiev.com/forum/viewtopic.php?f=22&t=4806&start=50#p42852

 

[boothegermanshepherd]

Thanks for the detailed reply.

I have had a look at the link and pictures

How do you access that lower board? Do you just unbolt the whole inverter with all the cables attached and turn it over or twist it upwards to access

Thanks

 

[kiev]

There's a picture on here somewhere showing the bottom lid removed with access to the control board while still mounted in the car. Maybe somebody remembers where that was posted? Jack the rear up and block it with safety stands. [it was in Lic's thread, page 7, http://myimiev.com/forum/viewtopic.php?f=23&t=4225&hilit=precharge+resistor&start=60#p41327]

Probably need to disconnect the 12V aux battery to make sure everything is off. There are some Hot all the time 12V circuits in the MCU, OBC and EV-ECU.

Once the lid is off then you will see the control board; there are some connectors and a few screws to remove and the board comes right out.

Here is Lic's thread with his work on this error, lots of good technical details in his thread.
http://myimiev.com/forum/viewtopic.php?f=23&t=4225&hilit=P1A15+No+Ready#p38258

 

[boothegermanshepherd]

Good evening.........

Another day! so I took the lower pcb out. After looking at it from the underside, I found it easier to remove the small looms and two coolant hoses, then turn the unit over with the HV still bolted in.

So the pcb is out and it looks brand new, I tested everything as per the instructions that were left for me except the capacitors, I dont have a meter here for them, ill have to test them tomorrow...............

What do I do next!!!!!!!

 

[kiev]

One thing i usually do is inspect all the solder joints under magnification looking for cracks and poor connections.

If all the blue resistors and ceramic caps on the control board tested okay, then i would remove the hybrid board and test it on the bench. i think this was discussed on page 7 of this thread where he sent it out to an electronics repair shop for testing and parts swap.

A good test might be to power up the hybrid and apply a test voltage of 1 to 4Vdc to the VH terminal with respect to VL, and monitor the output while heating and cooling the board (ceramic caps) with a hair dryer and cold air spray. This might prove out that the board is behaving intermittent with temperature changes, or that it has a bias with a lower output than input voltage (it is supposed to be function as a unity gain buffer).
Or,
another approach is just assume there is an issue and replace all possible components on the hybrid board.

Any forum members who have been through this same ordeal-- have any advice?

 

[boothegermanshepherd]

Exactly where do I make my connections with a voltage to the hybrid board and where do I test for the return voltage?

Is this with the hybrid board still fitted or removed?

I would like to pinpoint this exact fault and obviously repair it!

 

[Phximiev]

We don't have the firmware so don't really know anything about how the car is controlled.

There is a note in the HV wiring diagram section of the FSM:

Do not remove the A/C cable from the main battery.

The Leaf and Tesla use an interlock loop in the HV connectors of the pack, just don't know if these cars do.

i would guess that the status of HV to the AC compressor is sent over the CAN buss to the EV-ECU, and that may be triggering the permanent fault that can't be cleared.
http://mmc-manuals.ru/manuals/i-miev/online/Service_Manual/img/55/AC902570AB00ENG.pdf

Just read this and thought perhaps the Right to Repair laws could make the firmware available, particularly if an owner lives in MA.

https://www.greencarreports.com/news/1132830_biden-right-to-repair-action-could-benefit-tesla-owners-ev-economy

Just a thought.

 

[BlindMoose]

Having trawled through German I-miev sites, and Russian ones as well as English ones. The most common reason for the P1A15 fault, where the vehicle cannot be used is Extended Downtime. It's almost as if there is some software on some rom somewhere, that looses its ability to set the voltage charge time, so the main contractors cant be engaged.
I remember that early Acorn BBC b computers used to have battery backed up ROM chips that ran the RISC OS. If those batteries went flat, because the computer hadn't been used for an extended period, then the computer would not work. You had to go into Supervisor mode, in order to re-boot the Rom chipset, before you could use it again.
I wonder our I-mievs are suffering from the same fault.

 

[boothegermanshepherd]

Hi Blind mouse

Sent you a PM

 

[Gencis]

Just short info if someone is interested. Adding of the resistor helped to solve the problem. To this day I am driving imiev and never had this error again.