That blinking red light has a meaning. Every charger pattern, every fault code, every chuck and blade quirk — mapped to the actual model in your hand, by the people who've already taken the tool apart.
Independent · reader-supported · honest fixes. Some guides use affiliate links; we only recommend gear that genuinely works.
DeWalt DCG413B and DCG410B against Milwaukee M18 FUEL 2880-20 and 2888-20, from the manufacturers' own pages, and what the 3-inch "19,500 RPM" mini grinders are and aren't. Switch types, brakes and what to check first.
Cross-brand troubleshooting, platform-aware. Find the manual that matches the battery in your hand.
Shopping for a battery, charger or tool? These guides use each manufacturer's own pages and say what we couldn't verify.
Pick a brand and tool to see which battery platforms and models fit.
Pick your charger and its lights to get the manual's meaning and next step.
Enter your own costs and the tool's age to see whether to fix it or buy new.
DeWalt, Craftsman, Milwaukee and Makita kits, from the manufacturers' own pages.
DCF845, DCF860, DCF870 and Milwaukee 2953-20, torque shown as each brand labels it.
DCB1104, DCB1112, DCB1404 and DCB118: which packs each one charges.
What Milwaukee says and what to check on a third-party pack.
How to read 8Ah and 12Ah capacity claims.
Genuine vs aftermarket 8Ah packs.
Genuine vs aftermarket 7.5Ah listings.
What to check before you order.
AVID POWER, DEKOPRO, COMOWARE and PULITUO'S against named brands.
TSTAK, Craftsman, Keter and parts cabinets, with manufacturer dimensions.
What peak HP does and doesn't tell you.
Why the torque labels differ, and what each maker prints.
DeWalt and Milwaukee vs the 19,500 RPM mini grinders.
Circular, jig or reciprocating, from the manufacturers' own pages.
CFM and MPH vs the 990,000 RPM claims.
Most "battery dead" calls aren't dead cells. Once you know which part of the pack is which, you stop guessing.
Squeeze to release. Worn springs cause pack drop-out under recoil.
Power + comm to the tool. Clean with a pencil eraser — never sandpaper.
4 dots, ~25% per dot. Hold the button for 2s to read state of charge.
5 cells in series. 18.0 V nominal, 20 V peak. The "20V MAX" you see in the catalog.
Cuts at 2.5 V/cell. "Pack dead" usually means the BMS locked out, not that the cells are gone.
Kills charging above ~70 °C. Hot pack? Wait 30 min — don't force the charger.
Jump straight into the issues tradespeople and DIYers run into most — battery faults, chuck problems, blade wobble, and OPE starting issues.