Dell Precision 5510, AAM00 LA-C361P Rev:2.0 turns on, no image.

[andrhouseolly]

Hi.
I kindly ask you to help me solve the problem.
Dell Precision 5510, motherboard AAM00 LA-C361P Rev:2.0
The board turns on, there is no image.
Read more. When the power supply is connected, the front panel indicators light up briefly.
When you press the power button, the button indicator lights up. The board works
there is no image, there is no matrix initialization, there is no image on HDMI.
When turned on, the fans do not spin, but when they warm up they start spinning.
When you turn off the button, the fans spin up to full speed for a short time,
the board turns off.
Without memory, the board turns on, the front indicators blink in the sequence:
three times white, twice yellow. Several times, after which the board turns off.
Unfortunately, it's not possible to reflash the BIOS; I couldn't find a dump of the "Dell Precision 5510" anywhere
(out of curiosity, I tried dumps for Dell XPS 15 9550 AAM00 LA-C361P REV 1.0,
stopped responding normally to being turned on).
More details on the board.
I used the schematic "Dell XPS 15 9550 LA-C361P Rev 0.0 (M00).pdf".

There is no Power Up Sequence in this diagram, so Power Up Sequence
taken from the schematic "XPS 15 9570 LA-G341P MB 4PHASE Schematic.pdf" (p. 76)


According to "Power Sequence diagram" (p.53) "Dell XPS 15 9550 LA-C361P Rev 0.0 (M00).pdf":
+3VALW (+3VALW) - 3v
+5VALW (+5VALW) - 5v
PCH_1V (+1VALW) - 1v
+1.2V (+1.2V_DDR) - 1.2v
+0.6VS (+0.6VS) - 0.6v
+1.35VSDGPU (+1.35VSDGPU) - 1.35v
VCCIO_0.95V (+VCCIO) - 0.95v
+1.05VGPU (+1.05VSDGPU) - 1.05v
VGA_CORE (+GPU_CORE) - 0.9v
+VCC_CORE (+VCC_CORE) - 1.05v
+VCC_GT (+VCCGT) - missing !!!!!!!!
+VCC_SA (+VCCSA) - 1.08v

By +VCC_GT: no PWM sequence on PWM1_GT, PWM2_GT with PU1100 (ISL95829HRTZ-T)
forming +VCC_GT with PU1300, PU1301

According to "Power Up Sequence" (p. 76) "XPS 15 9570 LA-G341P MB 4PHASE Schematic.pdf":
Absolutely all levels rise, except for the last two "+VCCGT" and
"DDR_DRAMRST#" (on LA-C361P it's like "DDR4_DRAMRST#")

On display connector JEDP1:
+INV_PWR_SRC - 5v
INV_PWM - missing!!!!!!! (DV2 on anodes nothing)
DISPOFF# - !!!!!!!!!!! (DV1 on the anodes nothing)
EDP_PANEL_DAT - missing!!!!!!! (UV17 no EN signal - EDP_CTRL_EN_C)
EDP_PANEL_CLK - missing!!!!!!! (UV17 no EN signal - EDP_CTRL_EN_C)
At the inputs UV17 - DOCK_TNY_SMB_CLK, DOCK_TNY_SMB_DAT there are pulse sequences.

If anyone can advise or help, I will be very, very grateful.
Thank you.

[mon2]

What is the voltage to ground of the following?

EDPVDD
UV17 - pin # 8

[SMDFlea]

LINK to schematic - https://www.badcaps.net/forum/troubl...ematics-needed

Reminder: rules and organization of this section - https://www.badcaps.net/forum/troubl...f-this-section

Quote: If you request/offer BIOS/schematics/boardviews, please post in the appropriate subsection, and you can link to it in the troubleshooting topic.

[andrhouseolly]

UV17 - VCC (pin # 8), EDPVDD - 3.3v
RV545, RV546, RV548, RV549 - none.
UV17 - EN (pin # 5), EDP_CTRL_EN_C via RE107 (zero) to UE3 - (pin # B53 EDP_CTRL_EN) - missing.

[mcplslg123]

VCCGT is not of concern as it'll rise only under load. DRAMRST# must be 1.2V. What is the current consumption on your dc supply?
01.With ram stick
02.Without ram stick

[CyberDe@th]

You'll find Cleaned BIOS file in the attachment. It's helped me with one bricked Precision 5510. It hasn't worked with the other one. I don't remember where I've found it. Maybe at the BadCaps
https://www.badcaps.net/forum/troubl...-12-0-me-clean

[andrhouseolly]

Thank you dear CyberDe@th, but unfortunately the attached file is not available.

[andrhouseolly]

VCCGT is not of concern as it'll rise only under load. DRAMRST# must be 1.2V. What is the current consumption on your dc supply?
01.With ram stick
02.Without ram stick

Thank you. I heard and read about VCCGT, but I wasn't sure. Thanks for confirming.
DRAMRST# is missing (or rather “noise” is about 50 mV).
More precisely, here is H_DRAMRST# (PCH output, pin# BC14), via RD31 (short), to DDR4_DRAMRST#, with a pull-up to 1.2V_DDR.
I checked this chain, everything is intact, the resistors match. RESET is not cleared.

By currents (without peripherals, only RAM):

1. By +DC_IN (Main Power):
With ram stick - 1.3A (1.35A with warm-up)
Without ram stick - 1.2A (1.25A with warm-up)

2. By +1.2V_DDR:
With ram stick - 260mA-270mA
Without ram stick - 45mA-50mA

3. By H_DRAMRST#/DDR4_DRAMRST# (RD35 - 470 ohm):
With ram stick - 2.2mA-2.4mA
Without ram stick - 2.2mA-2.4mA

[CyberDe@th]

I've uploaded again. Let's see if it works this time...
Just in case, below you'll find the link to the Google Drive:
https://drive.google.com/file/d/1qmH...ew?usp=sharing

[mcplslg123]

Going by your measurements at post#8, try flashing the bios linked at post#9. Measure voltage on pin 1/6/3/4 of QH4. If you have oscilloscope,it will be much better to check pins on QH4.

[andrhouseolly]

Thanks to CyberDe@th for providing the dump.
Unfortunately the situation remains the same.
All supplies are raised (except +VCC_GT).
According to "Power Up Sequence", DRAMRST# is not removed.

According to measurements on QH4:
2,5 pin (+3VS) - PowerOff - 0V, PowerOn - 3.3V
1 pin (PCH_SMBCLK) - PowerOff - 0V, PowerOn - 3.3V, after switching on one packet (QH4_1pin).
6 pin (SMBCLK) - PowerOff - 3.3V, PowerOn - 3.3V, after switching on one package (QH4_6pin).
4 pin (PCH_SMBDATA) - PowerOff - 0V, PowerOn - 3.3V, after switching on one package (QH4_4pin).
3 pin (SMBDATA) - PowerOff - 3.3V, PowerOn - 3.3V, after switching on one package (QH4_3pin).

[mcplslg123]

Does these packets of data appears only once or they come in succession for 3-4 times? If the data comes only once,very very likely its CPU fault.

[andrhouseolly]

I checked again. The package appears only once, after switching on. Then there is only a constant high level.

[mcplslg123]

I checked again. The package appears only once, after switching on. Then there is only a constant high level.

This means ram is not detected properly by the system. Often the culprit is bios but sometimes its the memory controller inside CPU.
When ram is detetced properly ,you should see atlest 3-4 times burst of data packets .

[andrhouseolly]

This means ram is not detected properly by the system. Often the culprit is bios but sometimes its the memory controller inside CPU.
When ram is detetced properly ,you should see atlest 3-4 times burst of data packets .

Yes. Understood. I will “bury” the board. Thank you very much for the help.