TOSHIBA C40-D Cant use new battery

[Yosua]

Hi all my colleagues, today I want to ask you guys for help, maybe someone can take the time to help me with this toshiba C40-D mobo problem, the problem is, when using a new battery, it can't turn on even though I use a charger too and only lights the indicator flashes orange, I've swapped this new battery up to 3x but the result is still the same, and I can't find a schematic for this mobo, and this is the measurement for each pin on the ISL88732 charger ic when using a new battery (Without charger)

PIN1(NC)= 0V
PIN2(ACN)=0.23V
PIN3(VREF)=0V
PIN4(ICOMP)=0V
PIN5(NC)=0V
PIN6(VCOMP)=0V
PIN7(NC)=0V
PIN8(ICM)=0.10V
PIN9(SDA)=3.29V
PIN10(SCL)=3.29V
PIN11(VDDSMB)=3.34V
PIN12(GND)
PIN13(ACOK)=0.01V
PIN14(NC)=0V
PIN15(VBF)=11.5V
PIN16(NC)=0V
PIN17(CSON)=11.5V
PIN18(CSOP)=11.5V
PIN19(PGND)
PIN20(LGATE)=0V
PIN21(VDDP)=0V
PIN22(DCIN)=1.15V
PIN23(PHASE)=11.5V
PIN24(UGHATE)=11.5V
PIN25(BOOT)=11.12V
PIN26(VCC)=0V
PIN27(CSSN)=11.01
PIN28(CSSP)=11.01V


below I attach the schematic of the toshiba C40-A which uses the same charger ic

[mon2]

Re: TOSHIBA C40-D Cant use new battery

Does the laptop work to power on with the power adapter (remove the battery to test) ?

[Yosua]

Re: TOSHIBA C40-D Cant use new battery

Does the laptop work to power on with the power adapter (remove the battery to test) ?

when using a power adapter (without a battery) it turns on properly, but when using a power adapter with a battery it won't turn on, and using a battery only without a power adapter can't turn on either.

[mon2]

Re: TOSHIBA C40-D Cant use new battery

Need to check the BATTERY mosfet.

Locate the mosfet and then remove all power (no battery).

Use meter in resistance mode (2k scale is ok).

Check & post the resistance between:

source (1-2-3) & drain (5-6-7-8)
source (1-2-3) & gate (4)
gate (4) & drain (5-6-7-8)

Suspecting that you have a defective battery mosfet but it is only from the past reviews of similar cases.

Once you find the battery mosfet, post a pic or at least the full markings on the component. Assuming that this will be a common 8 pin N-channel mosfet with 8 pins as per above labels.

[Yosua]

Re: TOSHIBA C40-D Cant use new battery

Need to check the BATTERY mosfet.

Locate the mosfet and then remove all power (no battery).

Use meter in resistance mode (2k scale is ok).

Check & post the resistance between:

source (1-2-3) & drain (5-6-7-8)
source (1-2-3) & gate (4)
gate (4) & drain (5-6-7-8)

Suspecting that you have a defective battery mosfet but it is only from the past reviews of similar cases.

Once you find the battery mosfet, post a pic or at least the full markings on the component. Assuming that this will be a common 8 pin N-channel mosfet with 8 pins as per above labels.

thanks for your help, this is for battery fet measurement with 2k mode
s-d = 467 ohms
s-g = not showing
d-g = not showing

I think there is no problem with this battery fet.

I forgot to tell you, that this laptop can work when using the old battery but can't charge and must use an adapter

[mon2]

Re: TOSHIBA C40-D Cant use new battery

s-d = 467 ohms

is a low reading.

reference - see the RESISTANCE chart for source-drain

http://electronicsbeliever.com/how-t...-is-defective/

laptop can work when using the old battery but can't charge

Can be caused by this battery mosfet being defective.

What are the markings on this mosfet ?

[Yosua]

Re: TOSHIBA C40-D Cant use new battery

is a low reading.

Reference - see the resistance chart for source-drain

http://electronicsbeliever.com/how-t...-is-defective/



can be caused by this battery mosfet being defective.

What are the markings on this mosfet ?

pq19 = 4439gmt

[Yosua]

Re: TOSHIBA C40-D Cant use new battery

is a low reading.

reference - see the RESISTANCE chart for source-drain

http://electronicsbeliever.com/how-t...-is-defective/



Can be caused by this battery mosfet being defective.

What are the markings on this mosfet ?

and this is the voltage measurement on pq19

using a new battery (without adapter)
pins 1,2,3= 11.12v
pin 4= 2.64v
pins 5,6,7,8=11.12v

using new battery and plugged adapter
pins 1,2,3= 19.12v
pin 4= 18.81v
pins 5,6,7,8=11.12v

[mon2]

Re: TOSHIBA C40-D Cant use new battery

Datasheet for the mosfet is attached.

It is a p-channel enhancement mosfet. So to turn this mosfet ON, the GATE must be more negative than the voltage on SOURCE / DRAIN.

reference:
http://www.learningaboutelectronics....hannel-MOSFETs

The gate voltage looks good to turn it ON.

Concern is if this mosfet is ALWAYS on due to damage since the resistance between source & drain is quite low for the mosfet.

I would consider to at least remove this mosfet -> measure the mosfet leads again when it is out of circuit but recommend to replace with a known good mosfet.

The laptop will have I2C (SMBUS) interface pins (SDA & SCL).

Without power & no battery, what are the resistance readings for these lines to ground ? Need to be sure that the battery gauge is working.

When you are using the laptop with the adapter AND the battery is connected, what does Windows report on the status of the mated battery ? Can Windows even find the battery ? What is the % charge reported by Windows ?

[Yosua]

Re: TOSHIBA C40-D Cant use new battery

for the resistance of the SDA and SCL pins on the 632 ohm battery connector for these two pins.

and when using an old battery it can light up but can't charge but the battery can be detected

[Yosua]

Re: TOSHIBA C40-D Cant use new battery

pq19 measurement when disconnected from mobo

s-d=497 ohms
s-g= not showing
d-g= not showing

[Yosua]

Re: TOSHIBA C40-D Cant use new battery

any one can help me?

[mon2]

Re: TOSHIBA C40-D Cant use new battery

Replace this mosfet and test again.

[Yosua]

Re: TOSHIBA C40-D Cant use new battery

Replace this mosfet and test again.

thank you sir for your advice, but i have replaced it and the result is still the same, does this have nothing to do with TEMP_BATT or pin ID on the battery connector?

[mon2]

Re: TOSHIBA C40-D Cant use new battery

What are the resistance readings for the replacement mosfets?

Which replacement mosfet was used for this repair?

Next, with the power on, what are the voltage readings for the I2C (smbus) lines. These should be ~3v3 for each.

With only the battery, what are voltage readings on the mosfet?

Post the above values.

[mon2]

Re: TOSHIBA C40-D Cant use new battery

Interested in the MBDATA and MBCLK voltage readings with the battery connected.

Be sure that the battery connector pins for these 2 lines are reaching the charger IC. You can confirm this with removing all power.

Meter in resistance mode (2k scale). Then check the resistance between the battery connector pin and the target IC. We cannot have a break on these communication lines.

[mon2]

Re: TOSHIBA C40-D Cant use new battery

when using an old battery it can light up but can't charge but the battery can be detected

Does this mean that Windows is able to report a battery % value?

While power adapter is attached, the battery % continues to deplete and does not charge? The resistance to ground for the I2C lines looks low so concerned if these lines are ok.

[Yosua]

Re: TOSHIBA C40-D Cant use new battery

What are the resistance readings for the replacement mosfets?

Which replacement mosfet was used for this repair?

Next, with the power on, what are the voltage readings for the I2C (smbus) lines. These should be ~3v3 for each.

With only the battery, what are voltage readings on the mosfet?

Post the above values.

for the smbus voltage everything is normal sir, there is no problem and appears 3v when using the battery or not using the battery, and I measured with a buzzer between the battery connector and this smbus pin there is no sign of a broken line

and when using only batteries, the mosfet shows 11v and I think that's normal right?

for replacement mosfet have 478ohm sir

[Yosua]

Re: TOSHIBA C40-D Cant use new battery

Does this mean that Windows is able to report a battery % value?

While power adapter is attached, the battery % continues to deplete and does not charge? The resistance to ground for the I2C lines looks low so concerned if these lines are ok.

sorry for taking so long to post this, because i was trying to work on an easier mobo first, and now i'm still fighting for this c40d mobo