A1466 820-00165 weird issue..

[cruiser_]

really weird case of 820-00165.

came not starting at all (not even a quarter spin).

board on the bench, no battery. 11+1 signals/voltages all good but PM_BATLOW_L. No pulsing on PM_SLP_S5/S4_L.

With battery connected - a change in behavior! I am getting pulses up to S0 rails, short not evident on the rails I observed (looked at fall of the signal on mini scope). Pulsing every circa 5 seconds. No funny business on AMON/BMON isense.

Found corrosion around SPI ROM. Broken traces fixed / resistors replaced.

Now for the funny part.

Soldered U6100 from a random A1466 donor. The board on the bench - still dead. But with battery attached - it booted! (although resulted in kernel panics). Chime, screen, backlight all working.

Took a good clean spi dump (from the forum), replaced serial, fixed crcs etc, programmed, soldered to the board. Back to square one.

I feel like I am missing something obvious... help please

[mon2]

Re: A1466 820-00165 weird issue..

Remove the battery -> connect the magsafe adapter.

1) do you see a green / orange magsafe light?

2) What is the voltage to ground of PP3V42_G3H @ L7095, pin #2 ?

3) What is the voltage of PPBUS_G3H @ F7140, pin #2 ? pin #1 ?

[cruiser_]

Re: A1466 820-00165 weird issue..

1. yup, green -> orange
2. steady 3.41V
3. steady 8.57V on both pins

the S5 rails are steady (PP3V3_S5, PP5V_S5 -> S5_PWRGD); PP3V3_SUS ok; no PM_SLP_S5/4_L; no PM_BATLOW_L (yes, I am using original charger )

I would expect PM_BATLOW_L to be pulled up high by R1410 with no battery, right? Something pulls the line down in this case, since it is correctly high with battery connected (presumably 'let go' by SMC?).

[mon2]

Re: A1466 820-00165 weird issue..

Does the logic board boot with the adapter only?

[cruiser_]

Re: A1466 820-00165 weird issue..

nope, with no battery connected it's stuck at S5 (and no PM_SLP_S5/4_L - not even pulsing)
to be most precise - board + fan + DCIN board + DCIN flex.
DCIN board and flex have been tested with another logic board.

[mon2]

Re: A1466 820-00165 weird issue..

Using an 85W charger ?

Try with a SMC bypass.

[mon2]

Re: A1466 820-00165 weird issue..

What is the voltage to ground of SMC_BC_ACOK ?

[reformatt]

Re: A1466 820-00165 weird issue..

If you had corrosion in the U6100 area, then likely there is stuff elsewhere too. Look from side on for corrosion on components on the side of the board (like U8005, U1900, J6100). Intermittent boot is often crap under the SMC, so I remove the edge bonding and reflow it.

[cruiser_]

Re: A1466 820-00165 weird issue..

SMC_BC_ACOK is 3.34V. Board does not start in smc bypass. Using original 60W charger.

Here's the thing, the board is really clean, there was only one large blob over U6100 towards U7600. SMC is spotless.

With the replaced U6100 the board started a number of times in a row, it confuses a hell lot of me. Could be a coincidence, something connected in re-soldering... but how could that affect SMC bringing BATLOW signal down?

Have two 820-00165 side by side for comparisons; one thing I noticed that right before fan spins (in the working one), there is some short activity on CS line. In the bad board it is just pulled up flat.

Also, looked at I2C comms between ISL6259 and SMC; the difference between the boards was that one of the good one's requests looks like this:
write to 0x12 ack data: 0x14
read from 0x13 ack data: 0x80 0x00

while the bad one's response is
write to 0x12 ack data: 0x14
read from 0x13 ack data: 0x00 0x00

could be something, could be nothing. losing patience with this one

[mon2]

Re: A1466 820-00165 weird issue..

Using original 60W charger.

Does this same adapter allow for the other same model logic board to boot?

Would you have a beefier power adapter for testing? Louis' forum recommends to test with a 85W adapter. Worth a try.

SMC_BC_ACOK is 3.34V

Can you measure this same voltage on the working board ?

You should really have 3v42 on both boards.

PP3V42_G3H = 3v42 (not 3v34).

Check with another meter if available and with fresh batteries.

[cruiser_]

Re: A1466 820-00165 weird issue..

yeah the adapter powered all the other boards I have (ca 10).
Can surely try another charger.

good board has 3.42 for PP3V42_G3H & 3.38 for SMC_BC_ACOK.
bad one has 3.40 for PP3V42_G3H & 3.34 for SMC_BC_ACOK.

would it be a concern ?

[reformatt]

Re: A1466 820-00165 weird issue..

Power sequence from Logiwiki has PM_BATLOW_L preceded by your one wire circuit, my gut feel is this is SMC related (random stuff like this usually is). Despite it looking clean, I would still reflow it. I know from experience on working on a lot of these boards just to do that first to eliminate it. Also review your J9500 connector base and pins for damage or corrosion. Failing that, swap out your SMC.

[cruiser_]

Re: A1466 820-00165 weird issue..

funnily enough, according to the same power sequence I should not be getting PP3V3_SUS with PM_BATLOW_L low, yet I've had it since day one Anyway, thank you all for the suggestions, will try to reflow SMC tomorrow (so far had little luck with SMC reflows/reballs...)

[reformatt]

Re: A1466 820-00165 weird issue..

Only time a reflow doesn't work is if I miss some of the edge bonding from one of the corners. Use your microscope from side on to confirm none has remained after removal. I have some old (bent up) fine tweezers that I use to run under each corner.

Just make sure to pre-heat the board a bit with your hot air before diving in (use a fairly large nozzle too). Once it's close to the temp, apply your flux around the chip, then hit with the air proper. When the flux gets sucked in give the chip a nudge to make sure it flicks back to position.

[cruiser_]

Re: A1466 820-00165 weird issue..

I did not reflow SMC (just yet), BUT... while looking at the SD controller chip (u4500) at an angle I saw some slight corrosion marks. I reflowed it and... lo and behold, PM_BATLOW_L stays high all the time, even without battery connected. I don't understand how the two could be related (since U4500 talks to PCH only), but it's there so...

Anyway, I am now in a situation of pulsing all 'higher' rails (including PPVCC_S0_CPU). There is no activity on CS lines for SPI at all (stays high all the time). I checked every possible connection between U6100, replaced U6101 just in case.

Checked all ISENSE and VSENSE and ALERT_L values/signals. Nothing stood out of the ordinary.

Supposedly PCH should now try to read SPI, but it does not seem like it is even trying. Perhaps the rails are pulled down sooner than this?

[reformatt]

Re: A1466 820-00165 weird issue..

Cycling on/off is either a short on a rail, or it can't read U6100. Thermal camera is helpful for a short if that is the case. Just meter around each coil to double check especially L7630 (should be above 150 ohms at least for a good PCH). I also meter the switched supplies too by checking for volts on the current sensor pads (lke R8011) to see if volts are there during cycling.

For U6100, check your termination resistors (easy to knock off with hot air), and buzz them out to the ones to the CPU (under the RAM). Have seen a trace sometimes open on one of the lines.

[cruiser_]

Re: A1466 820-00165 weird issue..

yeah I've gone through all the rails and PCH signals; took note of the 'sharpness' of the fall after the spike. Nothing stood out power rail wise (slow slope)

some signals had very short spikes (e.g. SMC_DELAYED_PWRGD, PM_PCH_SYS_PWROK, PLT_RESET_L). No R8011 on my board (and a few other ones in the switches section).

You've got me worried there... L7630 shows some 200ohms on one meter and fluctuating ca 90 on another... strange yet the fall of PP1V05_S0 is very slow, doubt there's a short here.

[reformatt]

Re: A1466 820-00165 weird issue..

There are no resistors on those pads where R8011 is, they are a quick ref point for measurement of the switched power rails. When the resistance is low on the PCH, I generally find those machines are the ones that double pulse. The 1.05V supply will stick work fine with a damaged PCH.

[cruiser_]

Re: A1466 820-00165 weird issue..

Finally got some additional patience to look into this. And lo and behold, after another U6100 & U6101 re-soldering (checked the lines underneath for continuity) got the fan spin! yay. So it looks as if the intermittent results I was getting was due to some bad solder joints...

anyway, it all can't be too sweet The board does not chime / no USB activity on a ME-cleaned file. In SMC bypass fan goes full blast, but nothing beyond that.

However, it does start with an SPI content from another board.

I took '820-00165-02_Clear ME - tested OK.BIN', corrected the serial, hwc and son, fixed Fsys checksum. Is there anything else that needs to be done?

Appreciate yous' all help gents!


╔═══════════════════════════════════════════╗
║ ME Analyzer v1.283.3 r313 ║
╚═══════════════════════════════════════════╝

╔══════════════════════════════════════════════╗
║ A1466_moja_mod.bin (1/1) ║
╟──────────────────────────────┬───────────────╢
║ Family │ ME ║
╟──────────────────────────────┼───────────────╢
║ Version │ 10.0.35.1012 ║
╟──────────────────────────────┼───────────────╢
║ Release │ Production ║
╟──────────────────────────────┼───────────────╢
║ Type │ Stock ║
╟──────────────────────────────┼───────────────╢
║ SKU │ 1.5MB ║
╟──────────────────────────────┼───────────────╢
║ TCB Security Version Number │ 1 ║
╟──────────────────────────────┼───────────────╢
║ Version Control Number │ 3 ║
╟──────────────────────────────┼───────────────╢
║ Production Ready │ Yes ║
╟──────────────────────────────┼───────────────╢
║ Date │ 2014-12-02 ║
╟──────────────────────────────┼───────────────╢
║ Size │ 0x17D000 ║
╟──────────────────────────────┼───────────────╢
║ Chipset Support │ WPT-LP ║
╚══════════════════════════════╧═══════════════╝

[cruiser_]

Re: A1466 820-00165 weird issue..

Got it working with some other dump, installed monterey no problem, firmware got updated in the process. Consider this macbook fixed.

Once again, thank you all for contribution and help!