SDJ01RM vacuum robot not powers on, all dead

[ex250]

Hi friends, I have this vacuum robot at home that is not starting any more, no leds working, power button doing nothing, battery reading seems ok arround 14.4v, I suspect that mainboard is faulty, seems that there is not any clear brand model on it, and of course could not find any schematic. The trand of the vacuum is the Roidmi SDJ01RM, on some sites appears as vacuum mop Eve plus 60 or similar

If any one could point for where to start... would appreciate, new board is quite expensive arround 100 USD or more

Many thanks and Merry Christmas to all

[stj]

yours or a customers?
if your very lucky the fault will be a sensor or switch.
that board looks like a nightmare to work on - sprayed with plastic coating on black fiberglass.

best solution is this frankly!
https://numatic.com/products/cleanca...l-dry-vacuums/

[ex250]

Originally Posted by stj

yours or a customers?
if your very lucky the fault will be a sensor or switch.
that board looks like a nightmare to work on - sprayed with plastic coating on black fiberglass.

best solution is this frankly!
https://numatic.com/products/cleanca...l-dry-vacuums/

It's mine, personal use, yeah, the coating don't let guess much about... but is somewhat expensive to let it die, sheaves of dust are rioting around now...

[petehall347]

check fuses if switches work

[ex250]

Originally Posted by petehall347

check fuses if switches work

Thanks, will try to check for that

[ex250]

There are 3 fuses on the board, all of them seem OK, continuity to ground pins on both sides

I tried to check the main switch, but couldn't figure how to check this ones, there are 12 pins wired, tested several combinations but not found any on/off activity.

[ex250]

Well working again these days with some free time, accidentally checked that the power button is ok, if pressed, with a new battery connected (just to discard that) there was a part of a board getting hot, I have some sensibility damage on my hands, and the temperature takes some time to me to be detected, but seems that one chip with a 6118A heats when the power on button is pressed.

Is a voltage regulator, should it be on short? or something is in short making it being hot? Will try to make come reads on it.

Any help would be appreciated as always

[lotas]

These are LDO Regulators at 3.3V Check the resistance at the output, if it is low, then look for what could be shorting on this bus.

[ex250]

Originally Posted by lotas

These are LDO Regulators at 3.3V Check the resistance at the output, if it is low, then look for what could be shorting on this bus.

There is a short to ground at the input Vin pin (center one) how the hell warms up then?it's earthed on 2 pins of three.

[CapLeaker]

Hmm… continuity on both sides of the fuses to GND? I guess you got a short somewhere.

[ex250]

Originally Posted by CapLeaker

Hmm… continuity on both sides of the fuses to GND? I guess you got a short somewhere.

Was strange for me too, maybe on the input side from the battery, hard for me without any scheme of the board

[stj]

remove the regulator and then check the resistance of the input and output pads on the pcb to ground.
do it in both directions incase there is a diode involved

[ex250]

Originally Posted by stj

remove the regulator and then check the resistance of the input and output pads on the pcb to ground.
do it in both directions incase there is a diode involved

Just done;

Between
P1 GND to GND - 0,3 Ohms
P2 VIN to GND - 1,3 Ohms
P3 Vout to GND- variable stopted at 30,70K
Inverse:
P1 GND to GND - 0,3 Ohms
P2 VIN to GND - 1,3 Ohms
P3 Vout to GND- variable stopted at 46,00K

[ex250]

Before removing the regulator, just tested voltages at that pin regulator pin 2, somewhat confused, but with the battery plugged, on the Vin there where 14,4v (same as battery +) GND was OK, no heat, until power pressed, the heat appears again. Could be a good idea inject 3v on the Vout line?

[ex250]

Well, 3,3v injected at the VOut pin and nothing seems to be heated, the power supply also not revealed any amp of consumption, I have supposed that 3,3v is the maximum for the /33 on the regulator.

[ex250]

Originally Posted by ex250

Well, 3,3v injected at the VOut pin and nothing seems to be heated, the power supply also not revealed any amp of consumption, I have supposed that 3,3v is the maximum for the /33 on the regulator.

I'm stupid, injected on the Vin side, make a mistake reading and the Vout is the pin 2 of the regulator.

Tested the regulator alone for proper working and it's ok, 14v in 3,28 out.

Injected with caution from 1v on the out pin, and this time, correctly, and the U9 chip heats up quickly evaporating alcohol, it's named 12608D, I don't know it's function, maybe try a new one in place? it's a gyroscope?

Any ideas?

[lotas]

Rather, it is not 12608D, but I2608D aka (INVENSENSE ICM-20608D LGA-16 ACCELEROMETER + GYRO MULTI SENSOR I2608D)

https://aliexpress.com/item/1005003083972521.html

[ex250]

Originally Posted by lotas

Rather, it is not 12608D, but I2608D aka (INVENSENSE ICM-20608D LGA-16 ACCELEROMETER + GYRO MULTI SENSOR I2608D)

https://aliexpress.com/item/1005003083972521.html

Many thanks mate, the scheme found was just that one, it's likely that the short come from that one?

Seem that the pins 1,9,10,11,12,13,15 and 16 are shorted all together...

[ex250]

Well, one step more, just removed the IC and the shorts are still present, some smd caps near the IC, C117, C126 ans C128 seems that are shorted, will remove this ones to get some readings

[ex250]

Just removed the caps C117, C126 and C128 and they are not shorted, the short is still on the board, any idea about how to trace it?

For future reference: C117: 1,14uF (1uf)
C126 and 128: 110nF (0,1uf)