Lenovo G40-80 ACLU3 ACLU4 NM A362 not charging

[G_sene]

Ok. What is the exact voltage on the gate pin of PQ303?

See attached. PQ303 = P-channel mosfet. P-channel mosfets require that the gate voltage be lower than the voltage being passed between source / drain pins to ENABLE.

The resistors mated with the gate pin on PQ303 work together to build a voltage divider to lower the gate voltage. Respectively, when the gate voltage is LOW enough, the mosfet is being requested to be ON to pass the battery voltage onto the main power bus.

This PQ303 should be enabled when the power adapter is removed. Otherwise should be disabled.

When you have BOTH power adapter and battery connected, PQ303 should be disabled. Confirm it.

I put the jumper back on, but now I can't charge the battery from the power supply anymore.

[mon2]

Which jumper? Vin jumper? Review post # 120 and share the measurements.

[G_sene]

Which jumper? Vin jumper? Review post # 120 and share the measurements.

Only adapter:

Source - 19v
Drain - 1.89 (????)
Gate - 19v

Battery and adapter:

Source - 19v
Drain - 13.55v
Gate - 19v

Only battery:

Source - 12.85v
Drain - 12.85v
Gate - 0v

With VIN jumper PR304 has 19v in the both sides

[mon2]

Source - 19v
Drain - 1.89 (????)
Gate - 19v

Mosfet may be leaking or is from the high / low side charging mosfets. Remove all power. Meter in resistance mode.

Measure the resistance across this mosfet:

source / drain
source / gate
gate / drain

Post each measurement.

[G_sene]

Mosfet may be leaking or is from the high / low side charging mosfets. Remove all power. Meter in resistance mode.

Measure the resistance across this mosfet:

source / drain
source / gate
gate / drain

Post each measurement.

Source/drain - 1.76M
Source/gate - 820k
Gate/drain - 515k

[mon2]

Mosfet looks ok.

Battery and adapter:

Source - 19v
Drain - 13.55v
Gate - 19v

Battery should be charging. What does Windows show in this case?

[G_sene]

Mosfet looks ok.



Battery should be charging. What does Windows show in this case?

I'll check.

But isn't PQ303 an P-channel?
Shouldn't the gate voltage be lower?

[mon2]

Correct, PQ303 is P-channel. When both, the adapter & battery are connected, this mosfet should be OFF so the gate voltage is the correct value to remain OFF.

This mosfet should only be ON when the battery is the only power source. Then the gate voltge should be lower to enable, which it is.

[G_sene]

Correct, PQ303 is P-channel. When both, the adapter & battery are connected, this mosfet should be OFF so the gate voltage is the correct value to remain OFF.

This mosfet should only be ON when the battery is the only power source. Then the gate voltge should be lower to enable, which it is.

SOLVEEEEEEED =D

Thank you

I thought it wouldn't work because the gate was at 19v and the drain was very low.