I have a 820-2936-B board which was completely dead. There was a short on PP3V42_G3H, which was a short internally in the ISL. Replaced the ISL and the system booted.
But now it doesn't run on battery, and the system doesn't recognized a battery. The battery that was present was at 0V, so completely dead. Replaced with a known working battery, but still doen't see the battery.
With just the battery connected I am getting PP3V42_G3H, but nothing else.
On the battery connector (J6950) I am getting 3.42V on SMBUS_SMC_BSA_SCL (pin 4) and SYS_DETECT_L (pin 5), but 0V on SMBUS_SMC_BSA_SDA (pin 6).
So the clock for communication is likely present, but doesn't want to talk. Not sure what SYS_DETECT_L does, since is just seem to be a dud.
Since the ISL was shorted and likely drained the battery completely there might have been 10.5V on the SMBUS_SMC_BSA_SDA, and damaging the SMC. I measured the SMBUS_SMC_BSA_SDA line form U6950 to the ISL, which is not broken. SMBUS_SMC_BSA_SDA measures 0.480V to ground in diode mode, so seems there is no short.
Just to be sure I had a good ISL, I replaced it by another new one, same issue.
Are there anymore things I can try before concluding the SMC is "dead"?
But now it doesn't run on battery, and the system doesn't recognized a battery. The battery that was present was at 0V, so completely dead. Replaced with a known working battery, but still doen't see the battery.
With just the battery connected I am getting PP3V42_G3H, but nothing else.
On the battery connector (J6950) I am getting 3.42V on SMBUS_SMC_BSA_SCL (pin 4) and SYS_DETECT_L (pin 5), but 0V on SMBUS_SMC_BSA_SDA (pin 6).
So the clock for communication is likely present, but doesn't want to talk. Not sure what SYS_DETECT_L does, since is just seem to be a dud.
Since the ISL was shorted and likely drained the battery completely there might have been 10.5V on the SMBUS_SMC_BSA_SDA, and damaging the SMC. I measured the SMBUS_SMC_BSA_SDA line form U6950 to the ISL, which is not broken. SMBUS_SMC_BSA_SDA measures 0.480V to ground in diode mode, so seems there is no short.
Just to be sure I had a good ISL, I replaced it by another new one, same issue.
Are there anymore things I can try before concluding the SMC is "dead"?