openinverter forum

I bought a sports LDU, and a few years ago I got an O.I. board for it, and all this time it was waiting in the wings.
now I have both a power plant and a replacement brain. but I always get this error regardless of whether the high voltage battery is connected.
at the same time, the state of the inverter remains in the "run" status, but the accelerator does not respond and there is an error of the current sensor.
I took the board off the inverter and took it home for a thorough inspection of the soldering points under a microscope. everything is fine in this regard.
How do I properly use a multimeter to check the board on the table for errors in the dividers of the current sensors?

Who has any thoughts?

I applied 12 volts of power to the board and measured the voltage at two points near the connector of the current sensors. there were 0 volts.
While on another board (not programmed!) There are 1.9 volts in these places!
Could this be a problem or is it just because the board is without firmware?

I probably found the problem thanks to a randomly read description from Damien by mistake OverCurrent ))
at the diagnostic points I have 0 in one place (there are no current sensors, after all) and at the other point there are 3+ volts!!!
I'll look for where they came from.

At this point I can measure a square wave signal with 4.6 MHz and 5V level. Also on the pin below.

This is CLK-IA and CLK_IB. It is generated by IC7 and goes to the two test points via IC9. There is another test point near IC7/IC9

to be honest, I didn't understand anything. my knowledge of electronics is much worse.
I can measure the voltages at the points that are indicated to me, I can solder any wire to any place or transfer it from one board to another chip, I can cut any car into pieces and use welding to reassemble it.
But I do not understand the processes taking place in the chips.
I rewired all the connectors to a new board, but now it also has 0 volts in one place and 3.07 in the other. I suspect that now there will be an error on the first current sensor.

Very easy. With a board lying on the table and only supplied with 12V, regardless of whether it is programmed or not, approx. 2.5V should be measured with the multimeter on the two bottom pins. If this is not the case, IC9 is probably broken. If there is no 2.5V at the test point in the middle, IC7 is broken.

there are 0 volts on the old board in these places.
on the new board, at two points near the ic 13, 1.89 volts each. I'll check it out at ldu today. Thank you.

The version in the pictures has the dedicated clock chip so it will always produce a clock. Newer board versions branch off the STM crystal clock so only work when some firmware is running. They don't have ic7

johu wrote: ↑Wed Sep 18, 2024 8:57 am The version in the pictures has the dedicated clock chip so it will always produce a clock. Newer board versions branch off the STM crystal clock so only work when some firmware is running. They don't have ic7

will the board LDU V6 version have advantages over the one I have now? Is there no point in making a new one?

I did not find the reason why the old board did not work, I just have one set of connectors and it is difficult to transfer them every time.
I'll shelve it for later.
The new board works perfectly and the motor has the agility to jump on the spot from acceleration at a battery voltage of 51 volts!
Now you should really think about which car to buy for conversion with this engine!
Thank you all for your help in trying to solve the problem. When I find the culprit, I will update the information here.

@Romale did you ever figure out the issue?

I just made a new batch of five LDU V6 boards, and one of them is getting a HICUROFS2 error. However, despite the error, I can still put it in "Run" and spin the motor.

I see 2.37V at the test point next to IC9 and 2.31V at the two points on the bottom right. These seem a bit lower than the images @muehlpower posted above, and the other boards I made without the error.

How should I interpret this? Did I mess up soldering one of the JSTs, or is there a bad component on the board? Should I be concerned or ignore the error?

nubster wrote: ↑Sat May 17, 2025 9:05 pm @Romale did you ever figure out the issue?

......

How should I interpret this? Did I mess up soldering one of the JSTs, or is there a bad component on the board? Should I be concerned or ignore the error?

Hi. I'm not sure what to say to that.
No, I haven't figured out the problem.
I have only one LDU motor available and therefore only one set of connectors for soldering.
therefore, when the next board I took worked perfectly, I calmed down and did not re-transfer the connectors from the board to the previous one to find the cause of the errors.
moreover, I still haven't figured out where to use my sports LDU )))

I think 2.3V is the saturated value when the digital input stream is stuck at 1.
Follow the digital signal from connector to buffer to opamp and see if it's lost somewhere