Well shouldn't there be rectified DC getting to the PFC for precharging?
Leaf - Gen 2 PDM/OBC/charger no output power - L1/L2 charging
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The Gen 1 OBC is made by Nichicon; i haven't been on the mynisslaef site for some time ever since my 2012 was rear-ended and total loss.
Here are some part numbers and --> firmware update numbers:
i found this wiring diagram which shows a temperature line and the interlock lines. i suppose you are bypassing the interlocks to do your testing? i wish the PDM wiring diagrams were better documented.
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Here are some part numbers and --> firmware update numbers:
296A0 3NA0A → 296A0 3NA0E |
296A0 3NA1A → 296A0 3NA1E |
296A0 3NA2A → 296A0 3NA2E |
296A0 3NA3A → 296A0 3NA3E |
296A0 3NA4A → 296A0 3NA4F |
296A0 3NA5A → 296A0 3NA7A |
296A0 3NA6A → 296A0 3NA7A 296A0-3NA8A |
i found this wiring diagram which shows a temperature line and the interlock lines. i suppose you are bypassing the interlocks to do your testing? i wish the PDM wiring diagrams were better documented.
Not sure what this component is. It's not a grounding point. There are two other ones near the top-side's top control board's main chip.
- I also checked resistance of different pins of CN9006 against ground when this board was cold, and at room, temperature and found 5, 9 to be very sensitive to temperature. Haven't been able to find where they lead to on the power electronics top-board. And traced Pin 9 of CN9006 backup into the topside CN5401 and back to Out3 (Pin 12) of the ISO7241C IC151.
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- I also checked resistance of different pins of CN9006 against ground when this board was cold, and at room, temperature and found 5, 9 to be very sensitive to temperature. Haven't been able to find where they lead to on the power electronics top-board. And traced Pin 9 of CN9006 backup into the topside CN5401 and back to Out3 (Pin 12) of the ISO7241C IC151.
- At room temperature (at little warm in here, probably 24C) = ~11k
- At -15C for 10 minutes was ~20k ohms
- There's no TP point near this component at all.
Also, the temperature sensors could be I2C. This chip sits between the two SO7241C
1250WSR 1340X 17873 - ADUM1250 - Hot Swappable, Dual I2C Isolators
Checking this because B2840 DTC could also be an I2C failure.
![Passive circuit component Circuit component Green Hardware programmer Microcontroller]()
1250WSR 1340X 17873 - ADUM1250 - Hot Swappable, Dual I2C Isolators
- Vdd - Pin 8 - VDD from voltage regulator close to it. That reguklator also powers the SO7241C and has 5V - OutA (Pin 6), OutB (Pin 8), OutC (Pin 10) of the CN5401.
- SDA - Pin 7 - goes to Pin 10 of CN5401. Also, to Vdd through 47.2k ohm resistor
- SCL - Pin 6 - goes to Pin 12 of CN5401. Also, to Vdd through 46.7k ohm resistor
- GND - Pin 5 - goes to GND - Pin 2,4 of CN5401
Checking this because B2840 DTC could also be an I2C failure.
Chekcing out the R3022, R3023, R3024 and R3025 i think they are the thermistors in the PFC. R3022 and 3025 were missing from the board when I noticed. Checking to see how important and it seems R3022 isn't important as it goes to Pin 1 of CN2001 but that wire in the connector does not exist. R3025 that was missing, goes to Pin 20 and seems important. THese resistors are very dependent on temperature.
R3022, R3023 - near PFC
R3024 and R3025 - near the inverter
After some tests at -15C
K404 or (K409) B347 - LM358AST - Low-power dual operational amplifiers
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R3022, R3023 - near PFC
- R3022 was missing from the board and rightfully so, the circuit goes to Pin 1 of CN2001 and it has no wire attached in the connector by design. Otherside is to DC-
- R3023 is 9.7k at room temperature and goes to Pin 19. Otherside is to DC-
R3024 and R3025 - near the inverter
- R3024 was missing from board, and is also 9.7k and goes to Pin 2. Otherside is to DC-. Myabe this was a missing thermistor? Replaced with a 9.6k resistor for now.
- R3025 is also 9k and goes to Pin 20. Otherside is to DC-.
After some tests at -15C
- Both R3023 and R3024 exhibit the same changes in resistance dependent on temp.
- At 23C, 9.2k at time 0.
- At -15C, 20.2k after 17mins
- Backinside to 23C, 16.2k after 3 mins
- 13.5k after 6mins
- 11.5k after 10 minutes
- 10.88k after 14mins
- 9.92k after 35 mins
K404 or (K409) B347 - LM358AST - Low-power dual operational amplifiers
Without charging, the LDO on the PFC/Inverter top-control board gets 15V and outputs exactly 13V. I jumped this to Pin 7 to start the UCC28070 and the AC Input black relay clicks and it closes.
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- So, connected J1772 and then jump this pin to start the UCC28070 and the AC input black relay successfully closes at the same time.
- I'm getting switching 330 to 250VDC at the rectified 1 DC input into the PFC instead of constant 330VD. This is telling me the IGBTs are switching.
- I'm getting constant 380VDC out of the PFC and in to the Inverter stage at the Drains of the H-bridge IGBTs
- Still getting B2840-01 and B2840-96 DTC everytime.
- 0VAC between outputs of H-bridge.
- Getting only 15VDC, or unstable ~1.7VAC out the H-bridge inverter stage.
- No current draw.
- Shutting down charging, I am removing the J1772 plug first to avoid shutting IGBTs off instantly.
Just can't find a smoking gun. It's very odd.
Not planning on that. I have an IGBT tester coming and an oscilloscope.
So then in the Inverter/H-bridge control circuits we have:
- UCC2895Q - Phase-shifted full-bridge controller with enhanced control logic
- Has 13V Vin
- There is two of these chips, labelled UCC1-2, from left to right
- OutA,B,C,D on both chips are similar values.
- OutA,B,C,D vary between 8V to 13V
- UCC1 - Vdd - Pin 15 = 13V - should be above 10V to avoid Undervoltage lock out ✅
- UCC1 - EAOUT - EAN Pin 1, 2 = 13V
- UCC1 - Out A = TC2 InA = Low In for Q2003
- UCC1 - Out B = TC2 InB = High In for Q2002
- UCC1 - Out C = TC1 InA = Low In for Q2001
- UCC1 - Out D = TC1 InB = High In for Q2000
- UCC1 - EAP - Pin 20 goes to PC9001 (optocoupler) - Vin. (otherside of board) - ? to be measured
- UCC1 - SS/DISABLE - Pin 19 - otherside of board - TP9253 - should be > 0.5V, otherwise shut down. = ? to be measured
- UCC1 - REF - Pin 4 - should be > 5V, otherwise shut down = ? to be measured
- UCC1 - CurrentSense - Pin 12 - if 2.5V then shut down = ? to be measured
- UCC1 - Rt - Pin 8 = 105.2kohms
- UCC1 - DELAB - Pin 9 = 4.3k Ohms - to GND
- UCC1 - DELCD - Pin 10 = 4.3k Ohms to GND
- UCC1 - ADS - Pin 11 = 365 ohms to GND
- UCC1 - CS - Pin 12 = 420 ohms to GND
- UCC2 = PC6503
- UCC2 - Vdd - Pin 15 = 13V - should be above 10V to avoid Undervoltage lock out ✅
- UCC2 - EAOUT - EAN Pin 1, 2 = 13V
- UCC2 - Out A = TC4 InA = Low In for Q503
- UCC2 - Out B = TC4 InB = High In for Q502
- UCC2 - Out C = TC3 InA = Low in for Q501
- UCC2 - Out D = TC3 InB = High In for Q500
- UCC2 - EAP - Pin 20 goes to PC650 (optocoupler) - Vin.
- UCC2 - Ref - Pin 4 - Goes through 4.7k ohm resistor to PC650 (op
tocoupler) Vin
- UCC2 - Rt - Pin 8 = 105.2kohms
- UCC2 - DELAB - Pin 9 = 4.3k Ohms - to GND
- UCC2 - DELCD - Pin 10 = 4.3k Ohms to GND
- UCC2 - ADS - Pin 11 = 365 ohms to GND
- UCC2 - CS - Pin 12 = 420 ohms to GND
- UCC2 - SS/Disable - Pin 19 - otherside of board - TP9211
- TC4427AVA0 - 1.5A Dual High-Speed Power MOSFET Drivers- Has 13V Vin
- 4 of these chips, which im labelling TC1-4 and from left to right.
- All Ins and Outs are 0VDC for all four chips. **This is strange, going to remeasure this now knowing the circuits.
- TC1 - OutA = Low In for Q2001
- TC1 - OutB = High In for Q2000
- TC2 - OutA = Low In for Q2003
- TC2 - OutB = High In for Q2002
- TC3 - OutA = Low in for Q501
- TC3 - OutB = High In for Q500
- TC4 - OutA = Low In for Q503
- TC4 - OutB = High In for Q502
- IRS2113S - HIGH AND LOW SIDE DRIVER- All have 13V Vin
- There is 4 of these chips, two per H-bridge.
- From left to right it's Q2000, Q2001, Q2002, Q2003, Q500, Q501, Q502, Q503.
- HO = 13V, Vb = 13V, and Vs = 13V
- Vcc = 13V, COM = 0V, and LO = 0V
- SD - Shutdown Logic Input = ? to be measured
- Same for all 4 chips.
- IRS1 - High In Q2000 = TC1 OutB
- IRS1 - Low In Q2001 = TC1 OutA
- IRS2 - High In Q2002 = TC2 OutB
- IRS2 -Low In Q2003 = TC2 OutA
- IRS3 - Low In Q501 = TC3 OutA
- IRS3 - High In Q500 = TC3 OutB
- IRS4 - High In for Q502 = TC4 OutB
- IRS4 - Low In Q503 = TC4 OutA
Yup, they go through a chip K404 and that is also getting 5V. Havent finished tracing thoe circuits yet for R3022, R3023, R3024, R3025.
Found the issue. There was a hairline crack in two of the H-bridge/inverter's 2SK3697 IGBTs. They both failed open, and were impossible to detect with a multimeter until they were desoldered.
Replaced the two broken ones and thoroughly checked for any shorts related to the blown circuit, and replaced a few capacitors that I was unsure about or missing. Put it back together and voila now the OBC works. Still unsure what caused it to fail other than our house's electrical issues (sometimes below 90) or prolonged heat issues.
Anyways, turned out to be a cheap fix, a couple of hours of time to solder, and an overall huge learning experience.
cc: @Electric Land Cruiser
Highlights:
Thanks @kennybobby for helping understand this massive problem. If anyone takes this repair on, don't rush, and feel free to ask questions. If ever needed, and since my OBC is now on the shelf I can read values off any internal component.
Now off to figuring out my chademo issues, getting a local inspection and a build thread.
![Circuit component Passive circuit component Hardware programmer Font Computer hardware]()
Replaced the two broken ones and thoroughly checked for any shorts related to the blown circuit, and replaced a few capacitors that I was unsure about or missing. Put it back together and voila now the OBC works. Still unsure what caused it to fail other than our house's electrical issues (sometimes below 90) or prolonged heat issues.
Anyways, turned out to be a cheap fix, a couple of hours of time to solder, and an overall huge learning experience.
cc: @Electric Land Cruiser
Highlights:
- The top-side of the charger's AC input stage was working properly and sending 167VDC to the PFC section with two good 8.2ohms ceramic resistors On L1 at ~120VAC. Shouldbe 320VDC when charging at L2 at ~230VAC. A simplified factor of 1.39xAC input.
- Black relay wasn't engaging because of the B2840 fault. This didn't cause the ceramic resistors to burn up because there was no current being drawn after B2840 being thrown.
- The PFC section wasn't possible to test in-vehicle while charging, as the control ICs are under this board. But, out-of-vehicle, I verified these had no shorting on the power and IN/OUT pins. Also verified the PFC output voltage which was measured to be 380VDC at the drains of the H-bridge/inverter stage's IGBTs and that was enough to know the PFC was good.
- The missing resistors I mentioned on the top-side of the board are supposed to be missing in the design, even though the pads are there. Verified with my new OBC and opening it up.
- Verified 15V and 5V power and GNDs down into the bottom-side of the charger which goes to the bottom-side's top control board.
- Verified no shorting on basically all pins of the ICs mentioned in this article.
- A small handheld oscilloscope really changed the game and made it possible to verify the outputs of the UCC2895Q, TC4427AVA0, IRS2113S. Very very carefully.
- Make use of the proper tips for a multimeter and all the Test Points and pass-through points are easy to access. Rather than stripping the blue coating off every part you test.
- Found the 2 cracked IGBTs. Desoldered and resoldered new ones in.
- Retested everything and confirmed uniform values across all similar circuits with consideration of all datasheets.
Thanks @kennybobby for helping understand this massive problem. If anyone takes this repair on, don't rush, and feel free to ask questions. If ever needed, and since my OBC is now on the shelf I can read values off any internal component.
Now off to figuring out my chademo issues, getting a local inspection and a build thread.
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