Craftsman Craftsman T110 42" 17.5 HP Briggs & Stratton Single-Cylinder Riding Lawn Tractor MECH-WONT-START Error Fix: Engine Will Not Start or Crank

Error code MECH-WONT-START on the Craftsman Craftsman T110 42" 17.5 HP Briggs & Stratton Single-Cylinder Riding Lawn Tractor means: Engine Will Not Start or Crank. The riding mower engine does not turn over or start when the key is turned to START. Craftsman riding mowers have a 4-point safety interlock system that ALL must be satisfied before the engine will crank: (1) Operator must be seated on the seat (seat switch), (2) Parking brake must be fully engaged, (3) PTO/blade engagement lever must be in the disengaged/OFF position, (4) Transmission must be in neutral or speed control in the zero/park position. If any interlock is not satisfied, the engine simply will not crank — this is by design, not a malfunction. If all interlocks are satisfied: check the battery voltage (should be 12.4V+, charge or replace if low), inspect the 20A fuse in the wiring harness, verify the spark plug wire is connected, check that fuel is fresh (gasoline older than 30 days without stabilizer degrades), ensure the fuel shutoff valve (if equipped) is open, and verify the choke is set correctly for cold starting. Common causes in order: dead/weak battery, blown fuse, corroded battery terminals, faulty ignition switch, failed starter solenoid.

The most successful fix is "Test and Replace Starter Solenoid or Ignition Switch" (medium difficulty, ~45 minutes). Estimated DIY cost: $10-$20. HomeMD has 2 community-ranked fixes for this error.

This error is rated medium severity. It should be addressed soon, but your appliance may still function in a limited capacity.

Yes — the top-ranked community fix ("Test and Replace Starter Solenoid or Ignition Switch") is rated medium difficulty and takes about 45 minutes. Tools needed: Multimeter, Socket wrench set, Phillips screwdriver, Wire labels.

DIY cost: $10-$20. Professional repair typically costs $120-$180. Many homeowners save money by trying the top-ranked community fix first.

The Craftsman Craftsman T110 42" 17.5 HP Briggs & Stratton Single-Cylinder Riding Lawn Tractor has 8 other known error codes, including: MECH-BATTERY-CHARGING (Battery Will Not Charge or Hold Charge), MECH-BELT-WEAR (Drive or Deck Belt Premature Wear, Breakage, or Slipping), MECH-BLADES-WONT-ENGAGE (Mower Blades Will Not Engage When PTO is Activated), MECH-ELECTRICAL (Blown Fuse or Complete Electrical Failure), MECH-FLAT-TIRE (Flat Tire or Tire Will Not Hold Air), and 3 more.

Error code MECH-WONT-START also appears on 9 other Craftsman models: Craftsman B210 27cc 2-Cycle Gas Leaf Blower (210 MPH), Craftsman CMXGWAS021021 3000 PSI 2.3 GPM Gas Pressure Washer, Craftsman M110 140cc 21" Push Gas Lawn Mower, Craftsman R105 30" 10.5 HP Gear-Drive Rear Engine Riding Mower, M270 21 in 159 cc 3-in-1 Self-Propelled Gas Push Mower, S180 42cc Chainsaw, and 3 more. The fix may vary by model, so check each model's specific page for tailored repair steps.