820-00165. No PM_SLP_S4_L Fan Spins quickly but only on Battery....

[jb23]

Hi I have an 820-00165 in with no liquid damage and nothing looks burnt but board wasn't turning on. Checked around and is missing PM_SLP_S4_L

I have a clock signal, S5 voltages and PPBUS_G3H. Amber light on charger and PP3V42_G3H fine. However I only had 1V on SMC_PM_G2_EN.

Replaced SMC and I have 3.4V on SMC_PM_G2_EN, SMC_RESET_L is fine. However I have 0V on SMC_DELAYED_PWRGD and still no PM_SLP_S4_L

I put it all back together (I can't remember if these is one of those that needs a battery to power on) and noticed that I got no fan spin even in SMC bypass. However, with the battery connected and I plug the magsafe in or press the power button the fan spins fast for 1 second then turns off.

Replaced BIOS and Clock Chip like a monkey just in case but still no luck.

Any ideas what to check next? Throw it in the bin?

Really appreciate the support thanks!

 

[smiba]

SMC_DELAYED_PWRGD being low is to be expected when you're not in a S0 state.

Voltage of PP3V3_SUS? Probe this at C6100 or U6100 as I've seen the trace to the bios area gone bad before.

 

[dukefawks]

First put back original BIOS.
The SMC does not just die like that, it must have been corrosion. Did you use an SMC from identical donor board?

 

[jb23]

PP3V3_SUS is 3.3V BIOS traces look good.

Will do sorry Duke every time I do this you ALWAYS tell me to put back original BIOS. I'll learn one day...

I'm pretty sure it was an SMC from an identical board but in all honesty it came out of a box I previously labelled rather than straight from a board with a hole through it so cannot 100% confirm. I'll try another SMC and may as well run it through the ultrasonic cleaner for fun. Weirdly after replacing SMC I had 1V on SMC_PM_G2_EN for a while before it magically went up to 3.4V and has been stable since.

 

[jb23]

EDIT. THE SMC I USED HERE WAS ALMOST CERTAINLY AN 820-3437 BY MISTAKE. NOT AN 820-00165

OK so I tried another SMC off a donor board - absolutely dead - solid green light on charger after 3-4 attempts and 100% sure it was soldered correctly. I've run out of SMCs for the 00165 so I've ordered more from china. In the meantime I've put back the original SMC and original BIOS and stuck the board through the ultrasonic:


PPBUS_G3H 8.2
PPDCIN_G3H 16.14
PP3V42_G3H 3.412
PPVRTC_G3H 3.332
PP5V_S5 5
PP5V_S4RS3 0
PP5V_S0 0
PP3V3_S5 3.299
PP3V3_S4 0
PP3V3_SUS 0
PP3V3_S3 0
PP3V3_S0 0

SMC_ADAPTER_EN = now 3.4 (it was 1.07 before)
SMC_PM_G2_EN = 3.4
PM_SLP_S5_L 0
PM_SLP_S4_L 0
PM_SLP_S3_L 0

In SMC bypass mode I get fan spin for about 10-15 seconds (with heatsink on) then machine powers off. Any ideas where to go next or should I wait for my donor boards with SMCs to arrive? I have a load of 820-3437 SMCs but I'm guessing these won't work for this board?

 

[dukefawks]

PPBUS at 8.2V, is this without battery? If so then there is at least a problem with the SMC or ISL6259.

Also your symptoms have changed since the first post as your were getting only 1 second fan spin then. At this point it could be so many things....

 

[jb23]

PPBUS 8.2V was with battery (well it goes from 8 up to 8.57 and then drops to 0V before coming back again when battery connected? Is that normal?). 8.6V with battery disconnected.

My shipment of 820-00165 donor boards finally arrived and I put another SMC on - same symptoms as when I started when I was getting 1 second fan spin. This happens ONLY when both magsafe + battery are connected (automatic 1 second spin when battery connected and I then connect magsafe or vice versa) or I do an SMC reset with magsafe + battery both connected.

At least I'm back to where I started. Any ideas what to look for next?

 

[dukefawks]

3V3_S5, PPVRTC present? Green/orange light working? Checked all rails for shorts?