Specifications

Lenovo B50-30/B50-30 Touch/B50-45/B50-70

Toverifyasymptom,followthestepsbelow:

1. Turnoffthecomputer.

2. Removethebatterypack.

3. ConnecttheACadapter.

4. Makesurethatpowerissuppliedwhenyouturnonthecomputer.

5. Turnoffthecomputer.

6. DisconnecttheACadapterandinstallthechargedbatterypack.

7. Makesurethatthebatterypacksuppliespowerwhenyouturnonthe

computer.

Ifyoususpectapowerproblem,seetheappropriateoneofthefollowingpower

supplycheckouts:

• “CheckingtheACadapter”onpage21

• “Checkingoperationalcharging”onpage21

• “Checkingthebatterypack”onpage22

Checking the AC adapter

YouareherebecausethecomputerfailsonlywhentheACadapterisused.

• Ifthepower‐onindicatordoesnotturnon,checkthepowercordoftheAC

adapterforcorrectcontinuityandinstallation.

• Ifthecomputerdoesnotchargeduringoperation,goto“Checking

operationalcharging”onpage21.

TochecktheACadapter,followthestepsbelow:

1. UnplugtheACadaptercablefromthecomputer.

2. MeasuretheoutputvoltageattheplugoftheACadaptercable.Seethe

followingfigure:

Note:OutputvoltagefortheACadapterpinNo.2maydifferfromtheoneyou

areservicing.

3. Ifthevoltageisnotcorrect,replacetheACadapter.

4. Ifthevoltageisacceptable,dothefollowing:

• Replacethesystemboard.

• Iftheproblempersists,goto“LenovoB50‐30/B50‐30Touch/B50‐45/B50‐70”

onpage27.

Note:NoisefromtheACadapterdoesnotalwaysindicateadefect.

Checking operational charging

Tocheckwhetherthebatterychargesproperlyduringoperation,usea

dischargedbatterypackorabatterypackthathaslessthan50%ofthetotal

powerremainingwheninstalledinthecomputer.

Power system checkout

Voltage (V DC)

+20