frensis wrote:REVERSED sstuff ?
The battery connector has 6 pins, but only 4 used by the battery. The two unused ones are for the SMBus (smart battery). One of the thermistor pins are connected to ground. If you accidentally try to plug the connector in reversed then the normally 3.3V SMBus line gets +12V killing the SOC's I2C and the fuel gauge IC. If that's the case then its not repairable.
Its easy to pull the whole connector (plastic part) out from the motherboard, then it can be plugged in reversed.
That capacitor just made from a different material, looks good.
Enter test mode -> you should see the battery voltage of the side brush pins (on both if the side brush motor is connected).
Enable the sidebrush motor -> one of the pins shoud go to 0V. If not:
Check Q4, one of the pins should be around 5V (on the side that faces the small white circle, pins 1-4).
Be careful when measuring, shorting any of the pins on it will cause other components to fail.
If you are not seeing (nearly) 4-5V on any of the pins then:
Check U12. The small white circle marks Pin 1, and you count clockwise. Pin 1 should be 1.8V, pin2 0V, pin5 1.8V, pin6 5V. Pin4 is the output, same as Q4-s input.
Pin3 is the input from the main SOC, should be above 0V (maybe around 1-1.2V). If you do not see this voltage on it then the main SoC is faulty -> not repairable, but a workaround is possible. See http://www.robotreviews.com/chat/viewtopic.php?f=20&t=20413
SMBus: check that 3.3V is present on both the unused battery pins. If not -> try to measure resistance between ground and them. Should be open circuit. If not try knock off the ESD diodes and check for short again. If its short to ground (anything below 1k ohm basically) then you are in no luck, either the main SoC or the fuel gauge IC is defective. The later one can be replaced.
If 3.3V is present on the SMBus:
check that the 5V supply is working for the fuel gauge: one of the pins of U3 should be around 5V (3-5V). If thats not present then you have to reverse engineer which IC provides that (I didn't do it, mine was working). This 5V is always there, even if the bot is not powered on, but has power.
If the SMBus "seems ok" then attach a wires to the SDA and SCK pins of the fuel gauge IC (u4) and ground. Get a logic analyzer and check for bus activity, and specifically aim at the address of the fuel gauge IC and see if it pulls the ACK bit down during communication. If it does not then you can replace u4, see the link above.
BTW when you said you replaced all the capacitors, I hope that you put low ESR variants near the dcdc power supply. Its also worth checking that the ripple voltage of the power supplies are within a reasonable amount.
For the LCD I cant say anything.
These are all measured by the fuel gauge IC (u4), and they all seem like default/fallback values. u4, smbus or main SOC failure.
Did you do this measurement/log when the battery was disconnected?