Car electrics: battery, alternator, fuses

The vehicle network is 12 V with three heroes: BATTERY (starts, 60–80 Ah), ALTERNATOR (powers everything running, charges, 90–180 A), FUSES (sacrifice themselves on shorts — color = amps). Batteries die in winter: cold cuts a third of capacity. Signs: lazy starter, flickering lights. Multimeter check: 12.4–12.7 V off, 13.8–14.4 V idle — less means alternator or belt. Our /elektro/labor lab teaches the same laws: circuit, load, short.

• ●Jump-start: + to +, − to chassis ground (not terminal!), order saves ECUs
• ●Repeated blown fuse = never upsize — find the short
• ●Battery lasts 4–6 years: change BEFORE winter, not roadside