Job Summary
ApplianceLG Electric Range / Cooktop
ProblemOne knob activating two burners simultaneously
Root causeFailed power regulator switch (internal cross-contact)
Parts replacedPower regulator switch
Visits2 — diagnosis day 1, part sourced overnight, repair day 2
Repair time30 minutes on return visit
LocationSouthwest Ranches, FL

The Call

A homeowner in Southwest Ranches reported an unusual and dangerous problem with their LG electric range: every time they turned on one specific burner, two burners would activate simultaneously. The second burner — an adjacent one — would switch on at the same power level with no way to control it. Using the stove safely was impossible.

This is a less common but immediately recognizable symptom. When two burners activate from a single control knob, the issue is almost always in the power regulator (also called an infinite switch) — the component that translates knob position into a signal sent to the burner.

Diagnosis

1

Isolated the affected burner circuit

Identified which specific burner and knob were causing the problem. Confirmed reproducible: turning that one knob always activated both burners simultaneously.

2

Inspected the power regulator switch

Accessed the control panel. Removed the faulty power regulator. Found internal cross-contact — the switch's internal contacts had worn in a way that was sending signal to two output terminals instead of one.

3

Verified wiring harness

Checked that the wiring to both burners was correct and undamaged. The wiring was fine — the fault was entirely within the regulator switch itself.

The Repair

The replacement power regulator was ordered and sourced overnight — the specific LG part for this range model was not in our standard van stock for this visit, but we confirmed the diagnosis completely on the first visit.

We returned the following morning and replaced the power regulator switch. The job took 30 minutes. Both burners now operate completely independently and normally.

2
Visits (part sourced overnight)
30min
Repair time on return
Both burners independent
⚠️ Safety noteA stove with an uncontrollable burner should not be used until repaired. An unregulated burner can overheat cookware, cause burns, or start a fire. If you're experiencing this issue, switch off the breaker for the range until a technician can diagnose it.

What Is a Power Regulator Switch?

The power regulator (infinite switch) is the component connected to your burner knob. Unlike a simple on/off switch, it cycles the burner element on and off at varying rates to simulate different heat levels — "low" means short on-cycles, "high" means long ones. When the internal contacts wear or corrode, they can fail in ways that cause erratic behavior: a burner stuck on maximum, two burners activating together, or a burner that won't turn off. It's a mechanical wear part that eventually needs replacement on heavily-used ranges.

Frequently Asked Questions

This is almost always caused by a failed power regulator switch (infinite switch). The internal contacts wear and develop cross-contact — sending activation signal to two output terminals instead of one. It's a mechanical wear failure that requires replacing the switch.
No. An uncontrollable burner is a fire and burn hazard. Switch off the circuit breaker for the range and do not use it until the power regulator has been replaced by a qualified technician.
Power regulator switch replacement for an LG range in Broward County typically costs between $100 and $180 including parts and labor. iFixExpress waives the service call fee when the repair is completed.
Once the correct part is on hand, a power regulator switch replacement takes approximately 25–35 minutes. If the specific part needs to be ordered, we typically have it within 1 business day.