Briggs & Stratton 5100021YP Ignition Switch

The BRIGGS & STRATTON 5100021YP Lawn Mower Ignition Switch controls the electrical connection required to start and stop the engine. A faulty ignition switch can interrupt power flow, preventing engine starting and normal operation.

This part fixes the following symptoms:

• Engine will not start with the key

• Intermittent ignition operation

• Ignition key turns without response

• Loss of electrical power at the switch

• Worn or damaged ignition switch

Engine Will Not Start with the Key

Quick Check: Turn the ignition key and check whether the switch is supplying power to the starting circuit.

Fix Suggestion: Install a new ignition switch if the existing switch fails to complete the electrical circuit.

Prevention Tip: Keep the ignition area clean and protect it from excessive moisture.

Intermittent Ignition Operation

Quick Check: Check for loose electrical terminals or inconsistent switch operation.

Fix Suggestion: Replace the ignition switch if internal electrical contacts are no longer operating consistently.

Prevention Tip: Periodically inspect wiring connections for signs of corrosion or looseness.

Ignition Key Turns Without Response

Quick Check: Verify that the ignition switch responds correctly in each key position.

Fix Suggestion: Fit a replacement ignition switch to restore proper key-controlled electrical operation.

Prevention Tip: Avoid forcing or twisting the ignition key excessively during operation.

Loss of Electrical Power at the Switch

Quick Check: Inspect the ignition switch terminals for damage or poor electrical contact.

Fix Suggestion: Exchange the faulty ignition switch to re-establish reliable electrical continuity.

Prevention Tip: Regularly inspect the electrical system during scheduled maintenance.

Customer Experience: The BRIGGS & STRATTON 5100021YP Lawn Mower Ignition Switch restored stable key operation, allowing the mower to start consistently and operate without unexpected electrical interruptions.