EivoTech Laptop & Mobile Repair Master Course

Part 23 — Laptop Charging Fault Complete Master Workflow

Chapter 23: Adapter Connected Hai Lekin Battery Charge Nahi Ho Rahi — Complete Practical Diagnosis

Laptop charging fault bohat common hai, lekin har “not charging” fault charger IC ka fault nahi hota.

Common complaints:

Adapter connected hai lekin battery charge nahi hoti
“Plugged in, not charging”
Battery detect hoti hai lekin percentage nahi barhta
Battery 0% par stuck
Adapter unknown show hota hai
Laptop charger par chalta hai lekin battery charge nahi hoti
Battery sirf laptop OFF hone par charge hoti hai
Charging bohat slow hai
Charger lagane par charging LED blink karti hai
Battery charge hoti hai phir ruk jati hai
Battery kabhi charge hoti hai, kabhi nahi
USB-C charger se laptop charge nahi hota
Dell adapter wattage/type detect nahi hota
Battery par laptop chalta hai lekin adapter se charging nahi
Adapter voltage hai lekin main charging current nahi

Is chapter ka golden rule:

Charging fault ko Adapter → Input Path → Charger IC → Battery Communication → Battery Path → Battery Health mein divide karo.

1. Charging System ka Complete Basic Flow

Simplified:

Adapter

↓

DC Jack / USB-C

↓

Input Fuse / Protection

↓

Input MOSFETs

↓

Current Sense

↓

Charging Controller

↓

System Main Rail

↓

Battery MOSFET / Charge Path

↓

Battery BMS

↓

Battery Cells

Communication side:

Battery SDA/SCL

↔

EC / Charger IC

2. “Not Charging” ko Pehle Category Mein Divide Karo

Category A

Battery detect hi nahi hoti.

Category B

Battery detect hoti hai lekin charge nahi hoti.

Category C

Battery charge hoti hai lekin bohat slow.

Category D

Battery sirf OFF state mein charge hoti hai.

Category E

Battery percentage galat/stuck hai.

Category F

Adapter hi correct identify nahi hota.

Har category ka diagnostic route different hai.

3. Sabse Pehla Sawal

Kya laptop adapter par normal chal raha hai?

Agar NO:

Input charging section pehle diagnose karo.

Agar YES:

Adapter ka main power path at least partly working hai.

Phir battery charging branch narrow hoti hai.

4. Dusra Sawal

Kya battery BIOS/Windows mein detect ho rahi hai?

Agar NO:

Battery communication / connector / BMS side.

Agar YES:

Charging authorization/path side.

5. Teesra Sawal

Kya adapter correctly identify ho raha hai?

Especially:

Dell

Lenovo

USB-C PD systems

mein important.

6. Correct Adapter

Always start with:

Known-good.

Correct voltage.

Correct connector.

Correct wattage.

Correct manufacturer/ID system where needed.

7. Wrong Wattage Adapter

Laptop chal sakta hai.

Lekin:

Battery slow charge.

Not charge under load.

Performance reduce.

Warning show.

8. Adapter Voltage

Traditional laptop adapter commonly:

19V-class.

Exact value label se confirm.

USB-C system mein negotiated voltage hoti hai.

9. DC Jack Check

Check:

Physical damage.

Loose connector.

Center pin.

Burn marks.

Cable.

Solder.

10. DC Jack 19V Present

Input fuse.

11. Fuse ke Dono Sides

Example:

Input = 19.5V

Output = 19.5V

Fuse okay.

Input = 19.5V

Output = 0V

Fuse/path issue.

12. Input MOSFETs

Commonly two back-to-back MOSFETs.

Check:

Drain.

Source.

Gate.

13. MOSFET Input 19V, Output 0V

Do not replace MOSFET immediately.

Check:

Gate drive.

ACDET.

ACOK.

ACDRV.

Downstream short.

14. Charger IC Kya Karta Hai?

Charging controller manage karta hai:

Adapter validation.

Input MOSFETs.

Battery charge current.

Charge voltage.

Battery/system power sharing.

Current sensing.

Protection.

15. Common Charger IC Signals

Possible:

VCC

ACDET

ACOK

ACDRV

CMSRC

REGN

SRP

SRN

BATDRV

SDA

SCL

Exact names IC-specific.

16. VCC

Charger IC ki main supply.

Agar VCC missing:

Controller alive nahi.

Check source path.

17. ACDET

ACDET adapter-valid detection input.

Usually voltage divider se adapter voltage sense karta hai.

Agar ACDET wrong:

Controller adapter accept nahi karega.

18. ACDET Divider

Adapter voltage

↓

Resistor

↓

ACDET

↓

Resistor

↓

Ground

Ek resistor open/change:

Adapter input normal.

Lekin ACDET invalid.

19. ACDET Exact Voltage

Universal value memorize mat karo.

Charger IC datasheet se threshold/value check karo.

20. ACOK

ACOK:

Adapter valid indication.

Agar charger IC adapter ko valid samjhta hai:

ACOK expected state par jata hai.

Often active/open-drain style.

21. ACOK Low

Possible:

ACDET invalid.

VCC missing.

Adapter invalid.

Input fault.

Charger IC issue.

22. REGN

Many charger ICs internal regulated bias rail generate karte hain.

REGN

often important for:

Gate drivers.

Internal circuits.

Agar REGN missing:

Charger IC functional issue possible.

23. ACDRV

ACDRV input MOSFET gate drive signal.

Agar input MOSFETs open state mein expected hain:

ACDRV/CMSRC relation important.

24. CMSRC

CMSRC input MOSFET source reference/driver system ka part ho sakta hai.

Gate voltage ko ground se nahi, source ke relative samjho.

25. ACDRV Present, MOSFET Output Missing

Then check:

MOSFET itself.

Gate resistor/path.

Downstream short.

Correct pin identification.

26. ACDRV Missing

Then check:

ACDET.

ACOK conditions.

VCC.

REGN.

Controller logic.

27. Main System Rail

Input MOSFETs ke baad:

B+

VSYS

DCBATOUT

VIN

type main rail.

Agar laptop adapter par run karta hai:

Ye rail likely present.

28. Battery Detected But Not Charging

This is a very useful condition.

Battery communication likely at least partly working.

Check:

Battery health.

Battery temperature.

Charge limit.

Adapter ID.

Charge current path.

BATDRV.

29. Battery Not Detected

First:

Known-good compatible battery.

If same:

Check motherboard connector + SMBus.

30. Battery Connector

Inspect:

Positive pins.

Ground.

SDA.

SCL.

Detect/ID.

Corrosion.

Bent pins.

Burn marks.

31. SDA/SCL

Battery smart communication lines.

If battery info available:

Manufacturer.

Percentage.

Temp.

Cycle count.

then SMBus partially working.

32. SDA/SCL Both 0V

Possible:

Battery pulling bus low.

Motherboard short.

Pull-up missing.

Charger/EC fault.

33. Disconnect Battery and Compare

If lines recover:

Battery/BMS suspect.

If still low:

Motherboard/shared bus side.

34. Pull-Up Resistors

SMBus requires pull-ups.

If pull-up supply missing:

Communication fail.

35. Battery Detect Signal

Some designs use dedicated detect/ID line.

If wrong:

Battery physically connected but system says absent.

36. Battery Temperature

Battery reports or provides temp signal.

If temp invalid:

Charging can stop.

This is safety behavior.

37. Charge Limit Mode

Before hardware repair check:

OEM battery conservation mode.

Charge threshold.

Battery protection setting.

Example:

Stops at 80%.

Could be normal.

38. “Plugged In, Not Charging” Normal Kab Ho Sakta Hai?

Battery near full.

Charge limit enabled.

Battery too hot/cold.

Adapter underpowered.

OEM battery-health mode.

39. Battery Health

Worn battery may:

Detect normally.

Show 100%.

Still not accept charge properly.

Known-good battery comparison important.

40. BATDRV

BATDRV charger-controlled battery MOSFET gate signal ho sakta hai.

Battery charge/discharge path control mein important.

41. Battery MOSFET

Battery aur system ke darmiyan MOSFETs:

Charge.

Discharge.

Isolation.

Reverse protection.

manage kar sakte hain.

42. Battery Voltage One Side, Other Side Missing

Don't immediately replace MOSFET.

Check:

Gate.

BATDRV.

Protection condition.

Short.

Battery state.

43. Battery MOSFET Gate

Gate source ke relative analyze karo.

Same MOSFET rule:

VGS important.

44. SRP / SRN

Current-sense resistor ke dono sides charger IC monitor karta hai.

Signals commonly:

SRP

SRN

45. Current Sense Resistor

Very low value:

R010

R020

etc.

Iske across tiny voltage difference current ko represent karta hai.

46. Current Sense Resistor Open

Possible:

No charging.

Wrong current reading.

Power path issue.

Laptop unstable.

47. Sense Resistor Visual Damage

Burn mark/crack:

Strong clue.

But correct value/rating replacement mandatory.

48. Sense Resistor ko Wire se Bridge?

Never.

Current sensing/protection bypass ho jayegi.

49. Laptop Runs on Charger but Battery Not Charging

Main adapter/system path okay.

Now focus:

Battery detection.

Charge request.

Battery temperature.

BATDRV.

Current sense.

Battery BMS.

50. Laptop Runs on Battery but Adapter Not Charging

Focus:

Adapter validation.

Input MOSFET.

Charging controller.

Adapter ID.

Charge path.

51. Battery Charges Only When Laptop OFF

Possible:

Adapter wattage too low.

System load uses all available power.

Adapter ID issue.

Charging current limited.

Battery health/temp.

Power policy.

52. Example

Laptop needs 65W.

User uses 45W charger.

Laptop OFF:

Battery charges.

Laptop ON under load:

No charge / discharge.

This may be power-budget issue.

53. Adapter ID

Some brands identify charger using smart pin/data line.

If ID missing:

Laptop may still receive voltage.

But charging/performance restricted.

54. Dell Adapter ID

Common clue:

“The AC power adapter wattage and type cannot be determined.”

Possible:

Adapter center pin.

DC jack ID line.

Cable.

Board-level ID circuit.

EC.

Adapter itself.

55. Dell 19.5V Present But ID Missing

Do not replace charging IC first.

Check adapter ID path.

Because charger voltage and identity separate.

56. HP Smart Pin

HP systems may use adapter identification/smart pin.

Same concept:

Power voltage present ≠ adapter accepted fully.

57. Lenovo Adapter Identification

Different generations use different identification methods.

Exact model-specific circuit check.

58. USB-C Charging

USB-C laptop mein charging flow:

Charger

↓

CC1/CC2

↓

PD controller

↓

Power negotiation

↓

VBUS MOSFET/OVP

↓

Charger IC

↓

Battery.

59. USB-C 5V Only

If laptop requires higher PD contract:

5V only may indicate negotiation not complete.

Check:

Correct cable.

Correct charger.

CC1/CC2.

PD controller.

60. USB-C Higher Voltage Negotiated

If PD meter shows required higher voltage:

USB-C PD stage partially working.

Now downstream charging path.

61. USB-C 20V Present at Port but Charging IC VCC Missing

Check:

OVP.

Input MOSFET.

Fuse.

VBUS power path.

62. USB-C Charges From One Side Only

Type-C connector orientation clue.

Check:

CC1/CC2.

Connector contacts.

PD controller/mux.

63. Charging LED

Charging LED useful clue.

But LED status alone final proof nahi.

Could be EC controlled.

64. Charging LED Blinking

Manufacturer-specific error/state.

Could indicate:

Battery fault.

Adapter issue.

Thermal.

Charging state.

Use exact service documentation.

65. Charging LED ON but Percentage Not Increasing

Possible:

Charging current very low.

Battery worn.

Gauge issue.

OS display delay.

System load equal to input.

66. Battery Percentage Stuck

Example:

0%.

55%.

99%.

Possible:

Fuel gauge.

SMBus.

Battery health.

Calibration.

BMS.

OS/ACPI.

67. Percentage Stuck But Runtime Normal

Could be gauge/software issue rather than actual charging failure.

Check BIOS/OEM diagnostics.

68. Battery 0%, Charging Icon Present

Check:

Battery voltage/info.

Charge current.

Battery temp.

Battery full-charge capacity.

Known-good battery.

69. Battery Shows 100% but Dies Quickly

Battery capacity/health problem.

Not charging circuit necessarily.

70. Charging Starts Then Stops

Possible:

Battery reaches threshold.

Temperature changes.

Adapter power insufficient.

BMS protection.

Charger IC thermal/protection.

Intermittent connector.

71. Charging Intermittent With Cable Movement

Strong possible:

DC jack.

USB-C connector.

Adapter cable.

Solder joints.

72. Barrel Jack Loose

Input voltage may fluctuate.

Charging icon connect/disconnect.

Physical repair first.

73. USB-C Connector Damage

Dense contacts.

Possible:

VBUS contacts burnt.

CC pins damaged.

Cracked solder.

One orientation fail.

74. Adapter Voltage Drops During Charging

Possible:

Weak adapter.

Short/overload.

Input high resistance.

Wrong wattage.

75. Known-Good Adapter Same Drop

Then motherboard load/path stronger suspect.

76. Main Rail Stable but Battery Charge Current Zero

Focus:

Battery authorization/path.

BATDRV.

SMBus.

Battery BMS.

77. Charger IC Heating

Some warmth may be normal.

Abnormally hot:

Internal fault.

Gate-drive problem.

Shorted external part.

Battery path overload.

Use as clue only.

78. Input MOSFET Heating

Possible:

High RDS(on).

Partially driven gate.

Wrong replacement MOSFET.

Heavy current.

79. Sense Resistor Heating

Could indicate high current or damaged/high-resistance sense resistor.

Stop and investigate.

80. Battery Connector Heating

Possible:

High contact resistance.

Burnt pin.

Loose connector.

High current.

Repair connector properly.

81. Charging Current Low

Possible:

Adapter limit.

Battery near full.

Battery temp.

Charge policy.

Sense circuit.

Charger configuration.

Battery health.

System load.

82. Battery Charge Current Changes During Cycle

Normal charging current is not constant across whole charge cycle.

Near full battery:

Current may reduce.

83. Battery Fast Charge Then Taper

Normal lithium charging concept:

Early phase higher current.

Later phase current tapers.

Exact algorithm battery/controller-specific.

84. “Charging Slow” ko Measure Kaise Karein?

Don't judge only by icon.

Check:

Percentage change over time.

System load.

Adapter wattage.

OEM diagnostics.

Battery reported current if available.

85. Laptop ON Par Battery Discharges Despite Charger

Possible:

Adapter power < system demand.

PD contract too low.

Adapter ID missing.

Input path voltage drop.

Gaming/high load.

86. Laptop OFF Par Battery Charges

Strongly supports power-budget issue if all else normal.

87. Battery Suddenly Stops Charging at Certain Percentage

Check:

Charge threshold setting.

Battery temp.

Health.

BMS.

88. Battery Temperature Unrealistic

Example software reports impossible value.

Charging may be blocked.

Check battery/BMS/sensor communication.

89. Battery Detected But Serial/Health Missing

Communication incomplete.

Could be:

SMBus.

Wrong battery.

BMS fault.

90. Battery Communication and Charge Path Separate

Battery info can be perfect.

Still MOSFET charge path open.

Likewise battery power path can work while data path faulty.

91. Charger IC SMBus

Some chargers digitally controlled by EC.

If charger SMBus stuck:

Charging may fail even power pins okay.

92. Charger Programming

EC writes:

Charge current.

Charge voltage.

Input current limit.

to smart charger.

If EC firmware wrong:

Charging abnormal possible.

93. BIOS/EC Firmware and Charging

Wrong firmware may cause:

Battery not detected.

Adapter unknown.

No charging.

Wrong LED.

Fan weirdness.

Hardware checks first.

94. BIOS Update and Charging Fault

If charging fault started exactly after update:

Check correct BIOS/EC firmware.

But don't ignore battery/adapter basics.

95. Battery Replacement but Same Fault

If known-good compatible battery same:

Motherboard/adapter side stronger.

96. New Battery Not Charging, Old Battery Charges

New battery incompatible/faulty possible.

Physical fit does not guarantee compatibility.

97. Battery Connect Karne Par Laptop Dead

Possible:

Battery pack fault.

Battery rail short.

Connector issue.

Battery-path circuit.

Do not repeatedly reconnect suspicious battery.

98. Adapter LED Off When Battery Connected

Could be:

Battery branch short.

Charging MOSFET.

Battery pack abnormal.

Disconnect power and diagnose safely.

99. Battery Swollen

Stop normal charging/use.

Do not puncture, compress, open, heat, or direct charge.

Replace/service safely.

100. Battery Pack Opening Is Not Part of This Workflow

Laptop motherboard technician ke liye safest approach:

External diagnostics.

BMS communication.

Known-good pack comparison.

Internal lithium pack rebuilding bypass nahi.

101. Charging Schematic Reading

Search:

CHARGER

ACDET

ACOK

ACDRV

CMSRC

REGN

BATDRV

SRP

SRN

SDA

SCL

BAT

102. Charger IC Datasheet

Identify:

VCC range.

ACDET threshold.

REGN output.

Gate-drive behavior.

Current-sense pins.

Battery control.

103. BoardView Strategy

Locate:

DC jack.

Input fuse.

Input MOSFETs.

Charger IC.

Current-sense resistor.

Battery MOSFET.

Battery connector.

SDA/SCL resistors.

104. Safer Measurement Points

Instead of dense IC pins use:

Series resistors.

Large capacitors.

MOSFET gate resistor.

Test pads.

Sense resistor pads.

105. Charging Fault Master Measurement Table

Point	Expected Condition	Actual
Adapter	Correct input	____
Fuse In	Adapter voltage	____
Fuse Out	Adapter voltage	____
MOSFET Input	Adapter voltage	____
MOSFET Output	Main rail	____
Charger VCC	Present	____
ACDET	Valid	____
ACOK	Valid state	____
REGN	Present	____
ACDRV	Gate drive	____
Main B+	Stable	____
Battery Detect	Present	____
SDA	Idle/activity	____
SCL	Idle/activity	____
BATDRV	Correct state	____
Battery Path	Continuous	____

106. Case Study 1 — Laptop Runs, Battery Not Charging

Adapter correct.

Battery detected.

Battery temp normal.

Charge threshold off.

ACDET/ACOK good.

BATDRV missing.

Focus:

Charger control/EC conditions.

107. Case Study 2 — Adapter Unknown

Dell laptop.

19.5V present.

Laptop runs.

Battery not charging.

BIOS says adapter unknown.

Strong focus:

Adapter ID line/jack/adapter.

108. Case Study 3 — ACDET Missing

Adapter input 19.5V.

Charger VCC good.

ACDET 0V.

Divider resistor open.

Fix divider.

No charger IC replacement needed.

109. Case Study 4 — ACOK Missing

ACDET valid.

REGN good.

ACOK remains invalid.

Need charger datasheet conditions.

Controller/input sense issue possible.

110. Case Study 5 — ACDRV Missing

ACDET invalid.

Therefore MOSFET gates not driven.

Root cause ACDET side, not MOSFETs.

111. Case Study 6 — Input MOSFET Output Missing

ACDRV gate relation correct.

MOSFET input 19V.

Output 0V.

Downstream resistance normal.

MOSFET itself stronger suspect.

112. Case Study 7 — Battery Not Detected

Known-good battery same.

SDA/SCL both 0V.

Battery disconnected:

Lines still 0V.

Motherboard SMBus/pull-up issue.

113. Case Study 8 — Original Battery Not Detected

Known-good battery detects/charges.

Original battery/BMS faulty.

Replace battery.

114. Case Study 9 — Stops at 80%

OEM conservation mode enabled.

Normal behavior.

No motherboard repair.

115. Case Study 10 — Charges Only OFF

45W adapter on laptop expecting higher power.

Correct adapter charges while ON.

Power-budget issue.

116. Case Study 11 — USB-C 5V Only

Correct 65W PD charger.

Known-good cable.

Laptop requires higher contract.

Check:

CC1/CC2.

PD controller.

Not battery first.

117. Case Study 12 — USB-C Higher Voltage Present

20V-class negotiated.

Charging controller input after OVP = 0V.

Focus OVP/input path.

118. Case Study 13 — Battery Charges Intermittently

Moving charger changes charging status.

DC jack loose.

Physical fault.

119. Case Study 14 — Charge Current Low

Adapter correct.

Battery temp good.

System under heavy load.

Charge current rises when load removed.

Normal power allocation behavior.

120. Case Study 15 — Battery 50% Then Stops Charging

Battery temp suddenly reports invalid/high.

Charging blocked by safety logic.

Battery/BMS sensing fault possible.

121. Case Study 16 — Charger IC Hot

Input/output rails normal but IC extremely hot.

Battery disconnected still heats.

Charger IC/internal/external surrounding fault investigate.

122. Case Study 17 — Battery MOSFET Gate Correct, No Power Through

MOSFET D/S path abnormal.

Correct replacement after confirming no downstream short.

123. Case Study 18 — Sense Resistor Open

Battery detect okay.

No proper charging current.

Visual crack + electrical open.

Correct rated sense resistor replacement.

124. Case Study 19 — Percentage Stuck but BIOS Shows Normal Current

Windows battery display wrong.

Focus OS/ACPI/driver.

125. Case Study 20 — Battery Dies Quickly at 100%

Full-charge capacity very low.

Motherboard charging works.

Battery worn.

126. Charging Fault Quick Decision Tree

Adapter correct?

NO → Replace/test correct adapter.

Adapter recognized?

NO → ID/PD path.

Main rail present?

NO → Input MOSFET/charger input.

Battery detected?

NO → Battery/SMBus.

Battery health/temp okay?

NO → Battery issue.

Charge threshold active?

YES → Normal policy.

BATDRV/current path okay?

NO → Charger/battery MOSFET.

Current sense okay?

NO → Sense circuit.

All hardware okay?

Firmware/EC/software.

127. “Not Charging” Fast Shop Flow

Known-good adapter.
BIOS battery + adapter status.
Battery detected?
Charge threshold?
Battery health?
Main rail.
ACDET/ACOK.
REGN/ACDRV.
SDA/SCL.
BATDRV.
Current sense.
Known-good battery.

128. Adapter Unknown Flow

Correct adapter.

↓

Jack ID pin.

↓

ID/data line continuity.

↓

Protection/resistors.

↓

EC/ID controller.

↓

Firmware.

129. Battery Not Detected Flow

Known-good battery.

↓

Connector.

↓

Detect/ID.

↓

SDA/SCL.

↓

Pull-ups.

↓

EC/charger.

↓

Firmware.

130. Detected But Not Charging Flow

Charge limit?

↓

Temperature?

↓

Adapter identity/wattage?

↓

ACDET/ACOK?

↓

BATDRV?

↓

Current sense?

↓

Battery BMS?

131. Charges Slowly Flow

Adapter wattage.

↓

System load.

↓

PD contract/adapter ID.

↓

Battery temp.

↓

Battery health.

↓

Charge-current configuration.

↓

Sense circuit.

132. USB-C Charging Flow

Known-good charger + cable.

↓

CC detection.

↓

PD negotiation.

↓

VBUS.

↓

OVP.

↓

Input MOSFETs.

↓

Charging IC.

↓

Battery.

133. Charging Diagnostic Worksheet

Laptop Model: __________

Board Number: __________

Adapter Voltage: __________

Adapter Wattage: __________

Adapter Identified: Yes / No

Input Fuse In: __________

Input Fuse Out: __________

MOSFET Input: __________

MOSFET Output: __________

Charger IC VCC: __________

ACDET: __________

ACOK: __________

REGN: __________

ACDRV: __________

CMSRC: __________

Main B+: __________

Battery Detected: Yes / No

Battery Health: __________

Battery Temperature: __________

SDA: __________

SCL: __________

BATDRV: __________

Sense Resistor: __________

Charge Threshold: __________

Known-Good Battery Result: __________

Known-Good Adapter Result: __________

Final Fault: __________

134. Charging Repair ke Golden Rules

1. “Not charging” ka matlab charger IC kharab nahi hota.

2. Adapter voltage aur adapter identity separate cheezen hain.

3. Battery detect aur battery charge separate functions hain.

4. ACDET valid na ho to charger adapter accept nahi karega.

5. ACDRV missing ho to pehle controller conditions check karo.

6. BATDRV battery power path ka important clue hai.

7. Current-sense resistor ko bypass nahi karna.

8. SDA/SCL battery communication ke liye critical hain.

9. Charge limit/temperature/wattage fake charging faults create kar sakte hain.

10. Lithium battery pack ko open, bypass ya direct charge mat karo.

135. Part 23 Quick Revision

ACDET

Adapter detect voltage input.

ACOK

Adapter valid indication.

REGN

Charger internal regulator/bias output.

ACDRV

Input MOSFET gate drive.

CMSRC

Gate-driver source reference.

SRP/SRN

Current-sense inputs.

BATDRV

Battery MOSFET drive.

SMBus

Battery communication.

SDA/SCL

Battery data/clock.

Adapter ID

Brand-specific adapter recognition.

PD

USB-C Power Delivery negotiation.

136. Part 23 ka Sabse Important Lesson

Charging fault mein complete route:

Adapter

↓

DC Jack / USB-C

↓

Fuse

↓

Input MOSFET

↓

Charger VCC

↓

ACDET

↓

ACOK

↓

ACDRV / Main B+

↓

Battery Detect / SDA / SCL

↓

BATDRV

↓

Current Sense

↓

Battery BMS

Aur hamesha ye 3 sawal alag rakho:

1. Adapter accept hua?

2. Battery detect hui?

3. Charge current actually flow ho raha hai?

In teen stages ko alag prove karne se charging fault bohat jaldi isolate hota hai.

Part 23 Complete

Next — Part 24: Laptop Short Circuit Complete Master Workflow

Part 24 mein hum detail se cover karenge:

Short circuit ko properly identify karna.

Continuity beep vs actual short.

Main 19V rail short.

3V/5V rail short.

CPU VCORE low resistance vs short.

Shorted ceramic capacitor.

Shorted MOSFET.

Shorted IC.

Rail resistance comparison.

Schematic + BoardView se same net components find karna.

Short ko safely narrow down karna.

Input rail short par adapter LED off.

Shorted peripheral isolation.

Aur complete EivoTech Short Circuit Diagnostic Checklist, bina sensitive rails par blind high-current voltage injection ke.