The 2015 Model S is Tesla's first-generation long-range EV with proven battery longevity but notorious drive unit failures and some fit-and-finish issues. Early adopters see drivetrain rebuilds more often than battery problems.
Drive Unit (Motor/Transmission) Failure - Rear Unit on RWD, Front or Rear on AWD
Common · high severityTypical onset: 60,000-120,000 mi
Symptoms: Whining, humming, or clicking from motor area during acceleration or regen, Milling noise at highway speeds, Drivetrain error messages on dash, Reduced power or limp mode, Leaking drive unit fluid (red/orange color)
Fix: Tesla historically replaced entire drive units under warranty; out-of-warranty requires R&R and either Tesla reman unit or third-party rebuild. 8-12 labor hours for single motor, 10-14 for dual. Some owners on second or third drive unit by 100k miles. Tesla extended drive unit warranty to 8yr/unlimited miles for early cars, check if yours qualifies.
Estimated cost: $5,000-15,000
Main Battery Pack Degradation and Contactors
Occasional · medium severityTypical onset: 100,000-150,000 mi
Symptoms: Range loss beyond expected 10-15% (seeing 20-30% loss), Charge rate limited to low speeds at Superchargers, Contactors failing to close - car won't start or go into drive, High voltage isolation faults
Fix: Battery degradation is gradual and mostly acceptable, but contactor failures require pack removal and internal repair. Individual module failures rare but catastrophic. Pack R&R is 12-16 hours. Tesla does not sell modules separately; used/salvage modules or full pack replacement required. Original 85kWh packs holding up better than expected overall.
Estimated cost: $3,000-8,000 for contactors; $15,000-25,000 for pack replacement
MCU (Media Control Unit) Touchscreen Failure - Tegra 3 Chip
Common · medium severitySymptoms: Yellow border around touchscreen, Screen freezing, rebooting constantly, or going black, Slow response or ghosting, Backup camera failure, Loss of touchscreen functions including climate control access
Fix: The Tegra 3 chip in MCU1 fails from memory wear (eMMC). Tesla offered paid upgrade to MCU2 (Infotainment Upgrade, ~$2,500). Third-party shops can replace eMMC chip for less. Screen itself can also delaminate. 2-4 hours labor for MCU replacement. This is not a safety issue but severely impacts usability.
Estimated cost: $500-1,500 for eMMC repair; $1,500-2,500 for MCU upgrade
Door Handle Mechanism Failure
Common · low severityTypical onset: 40,000-80,000 mi
Symptoms: Handles fail to auto-present when approaching car, Handles stick in or out, Manual emergency release cable breaks, Frozen handles in cold weather
Fix: Early handles used gears and micro-switches prone to stripping and failure. Tesla revised design multiple times. Handle assembly replacement required, no rebuild option. 1-2 hours per handle. Tesla extended warranty covered many, but most 2015s now out of coverage. Keep emergency release functional.
Estimated cost: $400-700 per handle
12V Battery Failure and Power Conversion Issues
Common · medium severitySymptoms: Car won't wake up or unlock, Random error messages on dash, Accessories failing (windows, locks, displays), Clicking from frunk area, Main battery full but car dead
Fix: The DC-DC converter charges a conventional 12V lead-acid battery that powers all accessories and contactors. 12V battery typically lasts 3-5 years. When it fails, car is completely dead despite full main battery. Easy 0.5-hour replacement, but Tesla-specific battery recommended. DC-DC converter failure less common but requires 4-6 hours to replace.
Estimated cost: $200-400 for 12V battery; $1,500-2,500 for DC-DC converter
Suspension Upper Control Arms and Bushings
Occasional · low severityTypical onset: 70,000-120,000 mi
Symptoms: Clunking over bumps from front end, Wandering steering or poor alignment retention, Inner tire wear, Visible ball joint or bushing deterioration
Fix: Air suspension cars see earlier failures than coil. Upper control arms develop play in ball joints and bushings. Front arms 2-3 hours each side, rears 2-4 hours. Alignment required after. Not Tesla-specific but accelerated by curb weight (4,600+ lbs). OEM Tesla parts recommended due to load requirements.
Estimated cost: $800-1,500 per axle including alignment
AC Evaporator and Cooling System Leaks
Occasional · medium severityTypical onset: 60,000-100,000 mi
Symptoms: Loss of AC cooling, Moisture or condensation inside cabin, Fogging on windshield that won't clear, Coolant smell in cabin, High voltage system overheating warnings
Fix: Evaporator core can leak refrigerant or coolant. Dash removal required, 10-14 hours labor. Tesla uses separate coolant loops for battery, motor, and cabin HVAC. Hose connections and quick-disconnects also prone to seepage. Inverter coolant service often neglected, leading to overheating and reduced performance.
Estimated cost: $2,000-4,000 for evaporator; $300-600 for hose repairs
Buy one if major components (drive units, MCU) already replaced and you can DIY or have independent EV shop access - otherwise warranty expiration makes repair costs a gamble.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.