Electric range (coil and radiant glass-top): field service manual

Supply: the range gets L1, L2, neutral and (on 4-wire hookups) a separate ground at the terminal block on the back. Elements see about 240 V between L1 and L2; electronics and 120 V loads use one leg plus neutral. If one leg is lost, typically half the elements and sometimes the display go dead, while 120 V items on the other leg still work.

Knob-controlled surface units use an infinite switch. Inside, a small heater warps a bimetal strip that opens and closes the contacts; the knob position sets how long the contacts stay closed in each cycle. That is why elements glow, go dark and glow again at medium settings: cycling is normal, not a fault. On High the contacts stay closed.

The infinite switch has line terminals (L1, L2), heater terminals (H1, H2) and often a P terminal that feeds the 'element on' pilot light. Dual and triple-zone radiant elements use a matching dual/triple switch with extra outputs to switch the outer rings.

Touch-control cooktops replace infinite switches with relays on a cooktop or relay board; the board pulses the relays to set the power level and runs the 'hot surface' indicator logic.

Radiant elements under glass carry a built-in limiter. On many designs one pair of limiter contacts is in series with the coil and opens if the glass gets too hot; a second pair closes once the surface passes roughly 150°F and lights the hot-surface lamp until it cools.

Oven: the electronic oven control reads a platinum RTD sensor on the rear wall (about 1,080-1,100 ohms at room temperature, resistance rising with heat). During Bake it cycles the bake element (and on many models the broil element briefly for even preheat) through relays to hold the average temperature near setpoint. Broil drives the top element. Ovens with a hidden bake element have it under the cavity floor.

Self-clean ranges add a motorized door lock with position switches, and often a cooling fan and a thermal fuse/limit. The lock engages before the clean temperature rises and stays engaged until the cavity cools (LG training material cites below 500°F; other designs about 550°F).