Gencis
Posts: 69
Joined: Fri May 04, 2018 2:45 am

Re: Not able to drive. P1A15 error.

Mon May 10, 2021 7:54 pm

Thank you Kiev. I will give this information for the workshop that they check the board.

kiev
Posts: 1605
Joined: Sun May 03, 2015 7:15 am
Location: The Heart o' Dixie
Contact: Website

Re: Not able to drive. P1A15 error.

Wed May 12, 2021 1:49 pm

i have almost completed a trace of the ISA board. The final and biggest unknown is the part number/identity of the little 5-pin device on the top near the transformer and op amp.

i'm guessing that it is some kind of dual voltage regulator in an SOT 23-5 package, but the part has been etched on my board and no markings could be read. There is a via off of pin 4 that is an important control input signal to a chip on the bottom side.

Could you please take a look with a magnifying glass to see if you can read a part number? Anyone else with an open MCU control board?

On the top side is the AD8677 op amp, the 5-pin device, 2 transformers (1 signal and 1 for power), a Toshiba 4066 Quad bidirectional switch., and a 3 pin zener diode device. On the bottom side there is another 4066, a 3-pin dual diode, and a TL494 PWM power supply controller chip. So if would be possible to make custom boards if these are suspect and a vendor for the ISA215-HYB cannot be found.

A picture of the ISA board pinouts has been shown in other posts but i will list it here: 1 = VH; 2=VL; 3=Output Signal; 4=Gnd; 5=12V supply.

The P1A15 error code will be generated if that pin 3 signal (0-5V range) is not meeting the necessary ramp-up conditions that the EV-ECU is expecting.

So a fault in any of several parts on this little bitty board will disrupt or degrade the pack HV reading and brick the car. i think we could come up with a way to test this board on the bench with a power supply and oscilloscope. It has no reference designators so we will make up our own.

A quick look seemed to show that this pin 3 signal is sent to the MCU microcontroller; will trace it all the way when i get some free time.

Here is a markup of the bottom side
Image
kiev = kenny's innovative electric vehicle

coulomb
Posts: 294
Joined: Sun Jun 10, 2018 8:32 pm
Location: Brisbane, Australia

Re: Not able to drive. P1A15 error.

Fri May 14, 2021 3:42 pm

I'm not seeing any controller for the 4066 switch inputs in your list of parts. Could the 5-pin device be a tiny Pic micro or something? Something has to be converting voltage to frequency or PWM, to get the signal through the transformer.

This is of course a wild guess until the schematic trace is revealed.

Gencis
Posts: 69
Joined: Fri May 04, 2018 2:45 am

Re: Not able to drive. P1A15 error.

Fri May 14, 2021 8:39 pm

At the moment car and board are in the workshop. So I am not able to check if there is any code for the part you are interested.

Gencis
Posts: 69
Joined: Fri May 04, 2018 2:45 am

Re: Not able to drive. P1A15 error.

Mon May 24, 2021 5:23 am

My i-miev is still in the workshop.
They exchanged capacitors but it did not solve the problem.
They measured voltage in the battery and in MCU. The difference is 10V. I informed them about the possibility to use additional resistances for correcting voltage readings. With additional resistance, car goes into a ready state.
Now they ordered OPAMP and will change it. We will see the results.

kiev
Posts: 1605
Joined: Sun May 03, 2015 7:15 am
Location: The Heart o' Dixie
Contact: Website

Re: Not able to drive. P1A15 error.

Mon May 24, 2021 8:18 am

It might be that they could test the hybrid on the bench with a 12V power supply to pin 5 and return on pin 4. Then using an Input signal from 0 to 4 volts on pin 1 (VH) with return on pin 2 (VL), it should be possible to adjust and vary the Input and see the Output on pin 3 vary in the same manner. i would guess it would be around the same level but that depends upon the winding ratio of the transformer. If pin 3 is dead with no output or variation with pin 1, then the board will need additional troubleshooting.

The op amp is being used an a Unity Gain Inverting Buffer, so whatever voltage is Input on VH, should be seen as the same value with opposite polarity on pin 6 of the op amp. If this doesn't occur then the op amp is suspect.

The 12V to hybrid board Pin 5 with respect to Pin 4 is chopped and switched by the PWM regulator chip thru the Primary side of the power transformer. The Secondary of the transformer then creates a +5 and -5V supply for the op amp, and the input 4066, and provides a pulse to the "A" and "D" control pins to switch the gates of the input 4066.

There is a 5 pin and 3 pin device that is involved with the +/- 5V also but that is where is don't have the part numbers.

When the gates of the input 4066 are switched, then the op amp output signal sent thru the primary of the signal isolation transformer; the secondary then carries the isolated signal voltage to the 4066 on the Output side. The output 4066 is constantly gated by a bias voltage created by a voltage divider on the 12V power and the two tiny resistors above and to the left of the output 4066, so the signal runs right thru into a Low Pass Filter seen right at the Output pin 3 of the hybrid. there also appears to be a zener diode to limit over voltage of the Output.

will post a sketch of the trace

Good Luck i hope you can find the issue with their help.
kiev = kenny's innovative electric vehicle

Gencis
Posts: 69
Joined: Fri May 04, 2018 2:45 am

Re: Not able to drive. P1A15 error.

Mon May 24, 2021 8:37 pm

To Kiev: thank you. I will send this information for workshop.

kiev
Posts: 1605
Joined: Sun May 03, 2015 7:15 am
Location: The Heart o' Dixie
Contact: Website

Re: Not able to drive. P1A15 error.

Tue May 25, 2021 5:41 am

Sorry for the poor quality--a Kicad drawing is on my todo list.

The input side 4066 and PWM controller are on the bottom side of the hybrid board.

Image

The input op amp and the output 4066 are on the top side. The signal and power transformers are to the left and right on top side.

Image
kiev = kenny's innovative electric vehicle

Gencis
Posts: 69
Joined: Fri May 04, 2018 2:45 am

Re: Not able to drive. P1A15 error.

Wed May 26, 2021 12:40 am

Thank you. I passed this information to the workshop. Ordered OPAMP should arrive today. Let us wait for the results.

Gencis
Posts: 69
Joined: Fri May 04, 2018 2:45 am

Re: Not able to drive. P1A15 error.

Thu May 27, 2021 12:19 pm

Here is some information for the workshop.
They checked OPAMP. It works ok. inverted output (pin6) voltage perfectly coincides with inputted voltage. On ISA hybrid board pin3 voltage difference is 0.15V. If heated, pin3 voltage starts to drop even if OPAMP output remains stable. Also instead of +5 -5, they measure +5.6 and -6.1. Are such values in the limits of the error? It would be interesting to know measures from other cars. Also what such a difference in voltage means?

SOT23-5 marking is hardly readable. It looks like it could be "C5".

Also after heating the board, changes AC voltage on power transformer primary and secondary, DC changes accordingly.

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