MP 1,1-5,1 Upgraded 2009 Mac Pro Trouble Booting

[anewlanguage]

I have a 2009 Mac Pro which I made numerous upgrades to in order to run Mojave well (upgraded firmware, replaced CPUs, GPU, RAM, etc).

I ran Mojave on it for over a year with no issues. But I recently decided to sell it, so I wiped the drives, got a fresh OS on there, then it sat on a shelf for a few months. And now I'm having trouble booting it.

Upon pressing the power button, I get spinning fans and drives, but no chime and no display. Twice now I've randomly gotten it to boot normally without doing anything different, but after it went to sleep, the display didn't work when it woke.

Here's what I've tried for troubleshooting:
- Swapped with known good RAM
- Detached all peripherals
- Removed all drives except boot drive
- Removed optical drives
- Swapped GPU
- Reseated CPU tray
- Replaced OS drive

Has anyone ever seen behavior like this before, or have any idea what to try next?

 

[Macschrauber]

As it was sitting a while: Measure the rtc clock battery, below 3.0 volt is bad.

 

[anewlanguage]

Good thought. But no luck, I just replaced the 2032 battery and I'm still getting the same result

 

[Matty_TypeR]

Have you tried a NV ram reset? wait until it chimes 4 times at least. then release CMD + OPTION + P + R hold for 4 chimes then let it boot, hopefully it will. Make sure you use a USB keyboard as BT keyboards don't do it.

 

[anewlanguage]

Yea unfortunately I don't get a chime at all, even when holding those keys.

The other day I did get it to boot randomly, and I turned it back off and did that reset just for the hell of it. It continue to work for a little while, but then it went to sleep and I couldn't get any display when it woke up.

 

[tommy chen]

what does the diag switch show?

 

[anewlanguage]

Haven't tried that before, not sure what it means but pressing that button (with the power off) there is a single yellow led where the one is in your pic (top-left area), no other lights. What does that mean?

 

[tommy chen]

you should use the diag when it starts but not boot

 

[anewlanguage]

Oh gotcha. When I do that I get the exact same lights as in your photo

 

[Macschrauber]

Have you measured the rtc battery?

People replace the industry br2033 with cheap, used cr2032 and or not reset the smc properly. So they drain when sitting unused.

Also did you try the full nvram reset?

Sometimes it takes a minute or more until it shows live so hold the 4 keys for quite a time. Dont release when it chimes, keep it holding until it chimes 3 more times. This procedure could reset some vars in the rtc as well.

NVRAM is easy to get botched on crossflashs. If that procedure cures check it.

 

[anewlanguage]

I don't have a way to measure the battery, but did just replace it with a brand new one.

Also tried the reset holding CMD+OPT+P+R for a full minute, and don't get any chimes unfortunately

Also noticed that it looks like there's some kind of residue on certain parts of the pc board in the processor tray, right outside one of the heat sinks. When I dabbed a bit of it with a cotton swab it was dark. Not sure what that could be, nothing ever spilled on it. But I have heard of leakage from heat sealant, but not sure if this is what it is.

 

[Macschrauber]

You may take it apart and clean the board with isopropyl to get that away.


How's the exact behaviour of those status LEDs if you press the diagnose button and turn the Mac on?

It should

lower row: all 3 LEDs should lit for a second (like lamps in a dashboard), then the 2nd and 3rd goes off until the 2nd comes back after the firmware is ready. GPU ok gets lit when a EFI GPU's driver has loaded.

It's tuff to diagnose the box without a 2nd box to swap parts. I do this since forever and beside measuring a few points (for example 3,2v over the pon pads) and checking the fuses there is not much you can do as there are no schematics available.

Tracing the board is even tougher with that dark color.

If you cant measure a battery thats the 1st thing you should change. A meter costs almost nothing and has to be in the toolbox of everyone.

You can point the minus to the chassis and plus to the top side of the battery, better built in as the board pulls down the battery voltage a tiny bit.

 

[anewlanguage]

I did replace that battery with a new one, but no change.

Holding down the DIAG LED button during boot shows the bottom three buttons all lit green. None flash on or off. In the top lights, it looks like the PSU light is green, and the 5V light is yellow. Nothing seems to change after any amount of time.
I did briefly have someone else look at it and they were able to get it to boot with a different CPU tray. But when I got it back home, I was also able to get it to boot with the original CPU tray, though I haven't been able to do it again since that one time a few days ago.

 

[MrScratchHook]

I did replace that battery with a new one, but no change.

Holding down the DIAG LED button during boot shows the bottom three buttons all lit green. None flash on or off. In the top lights, it looks like the PSU light is green, and the 5V light is yellow. Nothing seems to change after any amount of time.
I did briefly have someone else look at it and they were able to get it to boot with a different CPU tray. But when I got it back home, I was also able to get it to boot with the original CPU tray, though I haven't been able to do it again since that one time a few days ago.

the fact that the other guy got it to boot with a different tray indicates to me that the tray you have seems to be going bad, i say seems because sometimes it boots and sometimes it doesnt. your 2 options is to take it apart(expert level)and clean it or buy a cheap one somewhere(noob level)i really like option 2. just easier.