The Short Answer
Ignition needs three things: a clean spark, gas at the burner, and a cap that seats correctly so the two meet. Most no-light burners fail on the first: spillover fouls the igniter electrode so the spark cannot jump cleanly, and the burner clicks and clicks without catching. A cap knocked out of alignment during cleaning, a weak spark module, or a spark switch shorted by moisture are the other usual causes. A true gas-supply problem is less common but is what we rule out first for safety.
Most Common Causes
- Fouled igniter. Food and cleaner on the electrode weaken or block the spark.
- Crooked burner cap. A cap seated off-center puts the spark out of reach of the gas.
- Moisture in the switch. A spark switch shorted by spillover fires every igniter at once.
- Weak spark module. The ignition module no longer delivers a strong, consistent spark.
- Blocked burner port. Debris in the port starves the flame even with good spark.
Notes by Brand
On Wolf and Viking sealed-burner ranges, cleaning and aligning the igniter and cap resolves most no-light complaints, and we test the spark module when it does not. On Thermador and Gaggenau cooktops, the spark switch and igniter are the common failures. On La Cornue ranges, we work symptom to cause and verify gas flow and spark at each burner. On Dacor and Bosch cooking equipment, a shorted spark switch behind the knob is a frequent cause of constant clicking.
Symptom Reference
| What You See | Likely Cause | Fix |
|---|---|---|
| One burner clicks, no flame | Fouled igniter or crooked cap | Clean and align igniter and cap, test spark |
| All burners clicking | Moisture shorting spark switch | Dry and reseal, replace switch if pitted |
| Weak or no spark anywhere | Failed spark module | Test and replace ignition module |
| Lights then goes out | Blocked port or low gas flow | Clear port, verify gas supply and valve |
| Yellow, lazy flame | Misaligned cap or dirty burner | Clean and reseat burner components |
Burner Will Not Light?
Book a diagnosis. Diagnostic and travel fees, if applicable, are confirmed before the appointment and before repair approval.