Says: "Charger lagaya, kuch nahi hota" — no lights, no fans, nothing.
Diagnosis (the power sequence ladder — Section 4.6 has the full tree):
Classic traps: dead CMOS makes some boards refuse to start — replace CR2032 first on old laptops · a shorted USB device or a shorted RAM slot kills the 5V rail — disconnect everything, boot bare board.
₹500–1500 depending on what dies (adapter swap is free profit: sell a genuine adapter).
Says: "Light aa raha hai, screen nahi" / "Fan chal raha hai par display blank".
Diagnosis:
₹500–1500 · RAM reseating service ₹200–300.
Says: "Charging me plugged dikha raha hai par charge nahi ho raha" / "Battery replace karne ko bol raha hai (battery is fine)".
Diagnosis:
₹500–1200
Says: "Works only with charger, dies without" or "battery charging slowly from 0% forever".
What it is: charging IC dead, a blown fuse in the battery path, or the battery's own protection board latched off after deep discharge.
Fix path: schematic for that board → locate the charging IC (BQ24xxx family common) → check its VIN, the battery fuse, the charge MOSFETs → replace the dead part → test charge current with the PSU/battery.
₹1000–2500 board level.
Says: "Charging loose hai, angle dena padta hai".
Diagnosis: wiggle the plug while watching the charge LED — flickers = jack solder cracked (very common — the jack takes all the plug-in force).
Fix: open → if the jack is on a cable/harness: replace the harness (cheap). If soldered to the board: reflow all 5+ pins with fresh solder (330–350°C), reinforce. If the barrel is physically broken: replace the jack (solder type or harness type).
₹300–600
When: a rail is shorted (diode mode beeps both ways to ground) and you must find the culprit.
Method (Adamant/Rossmann style): identify the rail's normal voltage on the schematic → set the PSU slightly above it with current limit 0.5–1A → inject into the rail → the shorted component warms up / the freeze-sprayed board shows the chip that behaves differently → remove/replace it → re-check diode mode.
Rules: current limit FIRST · never inject into the CPU core rail above ~1.2V · protect surrounding areas with Kapton · remove the battery and disconnect everything.
₹1500–3000 board level.
Protocol: full teardown immediately → remove CMOS, RAM, SSD → ultrasonic (when bought) or IPA scrub everything, especially under shields → dry 80–100°C hot air → inspect under scope → reflow corroded joints → reassemble step-by-step with function tests per stage → replace any corroded components.
Tea/coffee is worse than water — sugar residue is conductive and must ALL come off. Tell customers: stop using it, don't rice it, come fast. The odds drop every hour.
₹800–2000 + parts.
The professional flow: ask about data FIRST → backup if requested → bootable pendrive (Rufus + official ISO) → boot menu (F12/F9/F2 per brand) → install → drivers (brand tool or Snappy Driver) → Windows Update → activation question → hand over with a 15-min user tour.
Data rule: "Format kar do" ≠ delete my files. Ask twice. Write it on the job card.
₹300–500
Diagnosis: error code on BSOD? (note it — MEMORY_MANAGEMENT = RAM, INACCESSIBLE_BOOT_DEVICE = disk/controller) → safe mode test → startup repair → chkdsk /sfc/dism → system restore → if drive failing (slow + bad sectors): clone to a new SSD before it dies (SATA/M.2 enclosure!) → hardware: RAM test (MemTest86), disk health (CrystalDiskInfo).
₹300–600
Diagnosis: HDD still inside? (HDD→SSD upgrade is the single best-selling laptop upgrade ever — ₹2500–4500 with a 256/512GB SSD) → startup apps → temp/hardware (dust, thermal paste) → malware scan.
The upsell formula: SSD + thermal service = "laptop feels 3 years younger" — every service customer is a candidate.
Diagnosis: dust in heatsink (open, look — usually a felt blanket of dust) → fan spinning? → thermal paste dry (2+ years = repaste) → temperatures before/after (HWiNFO or BIOS) → if still hot: airflow path, dead fan, or board-level (rare).
Fix: full dust service + repaste = the classic ₹500–800 service job. Clean fan blades, vents, heatsink fins.
Diagnosis: grinding = bearing dead → replace fan (note the fan model printed on it). Fan not spinning at all = fan connector/fuse/fan dead. Loud constant spin = dust or thermal load.
Says: "Disk format ho gaya" / "Windows nahi khul raha, files chahiye" / drive clicking.
Ladder: 1) Connect the drive via SATA/M.2-to-USB enclosure to YOUR laptop → 2) healthy drive: Recuva/DMDE/PhotoRec for deleted files, or just copy-off a dying OS disk → 3) bad sectors: clone first (DDRescue/DMDE) then scan the clone, NEVER scan the original → 4) clicking drive = head failure → stop powering it, refer to a cleanroom lab (be honest). → 5) Recover to the CUSTOMER's drive, not yours.
₹500–2000 logical recovery · cleanroom cases = refer out.
Fix: identify the SOIC/WSON BIOS chip on the board → CH341A + clip (mind 1.8V chips!) → read → get the correct BIOS for that exact model (manufacturer site or BIOS databases) → flash → verify → test. WSON chips may need soldered-off + socket programming.
BIOS password: many laptops have it stored in a separate EEPROM or need manufacturer unlock (Dell: service tag code). Some are server-verified — be careful and honest about what's possible.
₹800–1500
Match: read the old panel's model number (on the back of the panel) — resolution, connector type (eDP 30/40-pin), size. Test the new panel BEFORE full assembly.
₹300–600 labor + panel.
Know: two types — (a) clip-on keyboard (older laptops: pry the top cover, unclip), (b) keyboard riveted INTO the top case (newer: entire palm rest assembly swap — quote the assembly). Spilled-liquid keyboards: clean/replace.
₹300–500 labor + keyboard.
Diagnosis: driver first (Device Manager), ribbon reseat, then replace the trackpad (often part of the palm rest).
What it is: hinges strip their mounting threads, crack the top/bottom case around the mounts (common!). Fix: re-thread with epoxy inserts, replace hinges, or case repair with epoxy + reinforcement. Quote honestly: a cracked case around the hinge is a bigger job than the hinge itself.
₹500–1000
Diagnosis: software (audio driver, default device) → headphone jack switch stuck (thinks headphones are in) → speaker resistance test → replace speakers (pair or single, note impedance) → board-level audio IC (rare).
Diagnosis: airplane mode, driver reinstall, antenna leads reseat on the WiFi card, reseat the M.2 WiFi card itself, test with a USB WiFi dongle (proves internal vs OS), replace the WiFi card (₹500–800 part, 5-minute job on most laptops).
Diagnosis: one port vs all ports (all = board-level/hub IC; one = that port) → physical damage (bent pins, loose solder — reflow) → driver (chipset drivers) → 5V power on the port pins (fuse!).
The job: check slot type (2.5" SATA, M.2 SATA, M.2 NVMe — check the notch key!) → clone the old drive (enclosure + Macrium/disk cloning) → swap → boot test. Also RAM upgrade at the same visit.
Know: DDR3/DDR4/DDR5 not interchangeable · SO-DIMM for laptops · speed matching. Fault symptoms: random BSODs, crashes under load → MemTest86 to confirm → replace the stick.
Diagnosis: privacy shutter physically closed (embarrassingly common), privacy setting, driver, ribbon cable after screen service, then camera module.
Beep code decoding (memorize the big ones): continuous beeps = RAM · 1 long + 2/3 short = video · repeated short = power issue. Manufacturer-specific tables online. Beeps are free diagnosis — write the pattern down before opening anything.
Symptom: display flickers when the lid moves, lines under pressure, works at one angle. Fix: replace the eDP cable (inexpensive, fiddly routing — photograph before removing).
Symptom: artifacts, driver crashes (nvlddmkm), works in BIOS but crashes in games, no external display. Reality: dGPU repair is advanced (reball/reflow territory, GPU VRAM). Diagnose: BIOS works but Windows GPU fails, or check with a Linux live USB. Be honest about difficulty; board-level repair or motherboard replacement.
Diagnosis: BIOS storage settings (SATA/NVMe mode, RAID vs AHX), the notch key (B-key vs M-key), reinstall the drive, test it in an enclosure (drive dead vs slot dead), BIOS update for NVMe support on older boards.
Fix: replace CR2032 (or the wrapped battery on thin laptops — sometimes a cable-attached pack). Two-minute job, big relief. Also fixes some "boot loop before Windows" oddities.
Symptom: fan runs full speed always, charging logic insane, power button dead but rails present. Fix: EC reflash (part of BIOS), EC reset (remove power + battery, hold power 30–60s), or replace the EC (advanced, schematic level).