The intelligent access key contains a removable mechanical key blade for the driver door if remote operation fails or the transmitter battery is low.
S550
2019 Mustang Owner Guide
S550 cars mix modern comfort with track-capable hardware. Owners get the most from these cars by learning the intelligent-access backup procedures, Easy Fuel funnel, MyKey, Track Apps, tire mobility kit, and the used-car checks that expose hard use.
Tips, Tricks & Emergency Access
If the car does not detect the intelligent access key, place the key in the backup slot at the bottom of the cupholder/console area and use the push-button start procedure.
If the power decklid release does not work because the battery is discharged, pull the rear left-side seatback cushion aside, insert the mechanical key blade into the hidden key slot, and turn it to release the decklid latch.
Easy Fuel requires the included funnel when filling from a portable fuel container. Aftermarket funnels can damage the capless filler.
MyKey can restrict settings, and Line Lock can be disabled through MyKey. Check admin key status before assuming Track Apps are missing or broken.
Line Lock is a track-use feature that holds front brake force so the rear tires can spin with minimal movement. It wears rear tires quickly and is not for public roads.
First Things To Do
- Get two working intelligent access keys, test the mechanical key blade, and locate the passive key backup slot.
- Check MyKey/admin key status and clear old restrictions only after confirming you have an admin key.
- Locate the Easy Fuel funnel, temporary mobility kit or spare setup, wheel lock key, tow hook if supplied, and jack points.
- Scan OBD-II codes/readiness and check for tune, emissions, misfire, throttle, and transmission faults before clearing anything.
- Baseline oil, coolant, brake fluid, clutch/brake feel, battery condition, tire age, alignment, and rear differential noise.
- If the car will see track use, replace unknown brake fluid, inspect pads/rotors/tires, read the track-use maintenance schedule, and disable driver aids only in a safe setting.
- Run the VIN through Ford and NHTSA recall lookups, then verify completed repairs in service records.
Buyer Checks
Look for track or drag-strip evidence: tire marbles, heat-checked rotors, corded rear tires, diff fluid seepage, driveshaft vibration, clutch smell, and rubber in the wheel wells.
Check for engine tune evidence, emissions deletes, mismatched intake parts, aftermarket forced induction, and whether the calibration and fuel system match the hardware.
Verify EcoBoost, GT, Performance Package, Shelby, Bullitt, Mach 1, GT350, GT500, California Special, and anniversary claims with VIN, window sticker, equipment, and original parts.
On convertibles, test top operation, quarter-window indexing, drains, rear glass, tonneau pieces, and trunk moisture.
Check panel alignment, front splitter damage, underbody scrapes, rear subframe alignment, and uneven tire wear after any lowered-suspension modification.
Confirm all keys, wheel locks, owner manual, mobility kit/sealant date, charging ports for accessories, and infotainment reset from the prior owner.