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Connector | Reading (volts) |
|---|---|
Main_Pi | ~0 |
Driver_Disp | ~5 |
Spare_5V_1 | ~5 |
Spare_5V_2 | ~0 |
Left_Cam/Rear_Cam | ~5 |
Right_Cam | ~5 |
MCI | ~13.7 |
Steering/Solar_sense | ~13.7 |
Spare_1 | ~13.7 |
Main_Disp/BMS | ~13.7 |
Center_Console | ~13.7 |
Rear_Cam_Display | ~13.7 |
L_Disp/Chgr_Interface | ~13.7 |
R_Disp/BPS_strobe | ~13.7 |
Spare_2 | ~13.7 |
Spare_3 | ~13.7 |
DRL/Brake_light | ~13.7 |
Turning_Light | ~13.7 |
Fan Control -
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Fan group 2
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Fan group 1
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As shown in the table, Main_Pi and Spare_5V_2 is not giving an output voltage (we are expecting it both to be give ~5V).
Ryan said that there’s no firmware reason for both Main_Pi and Spare_5V_2 to both be zero and he suggested to take a look at the I/O expander connected to both Main_Pi and Spare_5V_2 (which is U10 in this case). More specifically, the following pins: 13, 14, 15, 16, 17, 18. After confirming that these pins are not shorted with one another, I powered on PD and measured the following:
Pin | Reading (volts) |
|---|---|
13: MAIN_PI_B+ EN | ~3.3 |
14: MAIN_PI_DRVR_DISP_DSEL | ~0 |
15: DRIVER_DISPLAY_EN | ~3.3 |
16: 5V_SPARE_1_EN | ~3.3 |
17: 5V_SPARE_DSEL | ~0 |
18: 5V_SPARE_2_EN | ~3.3 |
From the table, you can see that the load switches (U13 and U14) are receiving the EN signals (MAIN_PI_B+ EN and 5V_SPARE_2_EN) so there must be something wrong at U13 and U14 rather than U10.
I first checked for shorts for the output pins of U13; in this case I checked pins 12, 13, 14 with GND, VBAT, 5V, and 3V3. I also did the same for the output pins of U14 (8, 9, 10). In both scenarios, there were no shorts. So then I then checked the surrounding components.
I did the following:
I checked the orientation of both LED14 and LED17 using the diode mode from a DMM, to make sure they weren’t soldered the wrong way (in this case they were both soldered correctly)
I checked for shorts with the other passive components (I found out that they were soldered correctly)
I added more solder to certain components that I thought were lacking enough to create a solid connection between the component and the pad
At this point, both LED14 and LED17 still did not turn on so I decided to measure the voltages of the input pins of U13 and U4.
So there must have been an issue with the components surrounding
EDIT THIS:
i found out that led14 turns on when i pushed down on pin2 of U13 (fixed this by soldering)
i find out that led17 turns on by probing pin 4 of R89 (most likely soldering issue)
i find out that led22 turns on by probing pin 4 of R115 (most likely soldering issue)
...