2015 Dodge Dart Check Engine Light Reset Guide
The 2015 Dodge Dart stores diagnostic trouble codes (DTCs) whenever the powertrain control module detects a fault. Clearing the malfunction indicator lamp (MIL) without solving the root cause only hides the issue temporarily and resets emissions monitors. Use the following workflow to diagnose the fault, confirm repairs, and perform a proper reset that keeps the light off.
- Applies to: 2015 Dodge Dart with 2.0L Tigershark, 2.4L MultiAir, or 1.4L MultiAir Turbo engines.
- Tools required: OBD-II scan tool that can read pending/permanent codes and live data, digital multimeter, basic hand tools, smoke machine for EVAP leaks (optional).
- Immediate caution: A flashing MIL indicates a catalyst-damaging misfire. Reduce engine load and diagnose ignition or fueling faults before continuing to drive.
Common 2015 Dart Codes and First Checks
| Code | Subsystem | Likely Cause | Quick Diagnostic Tip |
|---|---|---|---|
| P0300/P030x | Ignition | Coil-on-plug failure, worn spark plugs, injector clog | Swap coils between cylinders, inspect plugs for oil or coolant contamination, review misfire counters. |
| P0128 | Cooling | Thermostat stuck open, low coolant temperature | Check coolant level, verify thermostat operation in live data, inspect for radiator fan running constantly. |
| P0138/P0158 | Oxygen Sensor | Shorted downstream O2 sensor wiring, rich mixture | Inspect harness near exhaust, monitor sensor voltage for flat-lining above 0.9 V, confirm fuel trims are not highly negative. |
| P0456 | EVAP | Loose gas cap, purge solenoid leak, cracked vapor hoses | Perform smoke test, verify gas cap seal, command purge solenoid closed and check for vacuum decay. |
| P1CEA | MultiAir | Oil quality or hydraulic circuit issue in valve lift system | Confirm recent oil change with the correct 5W-40, inspect for low oil pressure, run MultiAir system relearn with scan tool if available. |
Systematic Diagnostic Workflow
- Record the data: Pull stored, pending, and permanent DTCs. Save freeze-frame information and inspect mode $06$ misfire counts. Photograph or export the data before clearing anything.
- Verify basics: Check engine oil level/condition (critical for MultiAir), battery voltage, grounds, intake ducting, and vacuum hoses. A voltage sag under 12.4 V can generate random U-codes.
- Address misfires first: For any P0300/P030x, inspect spark plugs (0.043 in gap), swap coils, and perform injector balance checks. Resolve misfires before chasing secondary catalyst or fuel-trim codes.
- Test subsystems: Use smoke testing for EVAP leaks, monitor upstream/downstream O2 voltage, and confirm coolant reached 180-200 F during a road test. For MultiAir faults, verify oil viscosity and consider a relearn procedure.
- Repair and retest: After component repairs, clear codes, road-test through a drive cycle, and confirm long-term fuel trims settle within +/-10%. Re-scan to ensure no pending codes remain.
Resetting the MIL After Repairs
- Use the scan tool: Choose the clear codes/Mode $04$ function after the repair. Do not disconnect the battery; that erases adaptive memory needed for smooth idle and transmission shifts.
- Verify monitors: With the engine running, confirm the scan tool shows no active or pending codes. Note which readiness monitors reset to NOT READY.
- Complete the drive cycle: Follow the cycle below to allow the PCM to run its tests. The MIL should stay off if the root cause is fixed.
- Re-scan: After the drive, check that no permanent codes remain and readiness statuses are COMPLETE. Permanent misfire codes require a successful drive cycle to clear even after repairs.
2015 Dart Drive Cycle Checklist
- Start the engine cold and idle for two minutes with the A/C and headlights off.
- Accelerate gently to 55 mph, holding steady throttle for five minutes to run fuel, O2, and catalyst monitors.
- Coast down to 20 mph without braking to trigger EGR and EVAP tests.
- Perform city-style stop-and-go driving for 10 minutes, maintaining fuel level between 1/4 and 3/4 of a tank.
- After the drive, let the engine idle for two minutes, then shut down and re-scan.
Preventive Maintenance Tips
- Change engine oil with FCA-approved 5W-40 every 6,000 miles to keep the MultiAir system healthy.
- Replace spark plugs at 30,000-mile intervals on the 1.4L turbo and 60,000 miles on naturally aspirated engines.
- Inspect and tighten the gas cap after every fill-up; replace it if the seal is cracked.
- Flush the cooling system at 10-year/150,000-mile intervals to prevent P0128 thermostat codes.
- Keep software current by applying PCM updates; dealers often release patches to refine MultiAir operation.
Frequently Asked Questions
Will disconnecting the battery reset the light?
Disconnecting the battery clears adaptive memory but does not remove permanent codes. The MIL will illuminate again as soon as the PCM reruns the diagnostic and sees the fault. Always fix the underlying issue before clearing codes with a scan tool.
How long can I drive with a steady check engine light?
A steady light indicates a stored fault that may not be immediately damaging, but the car should be inspected within a day or two. Continuous driving with rich mixtures or EVAP leaks can ruin catalysts and fail emissions tests.
Do I need a professional scan tool for MultiAir faults?
Entry-level OBD-II tools read generic codes, but MultiAir or transmission codes often require a tool that can access manufacturer-specific data. If you see P1 codes or repeated oil-pressure faults, enlist a technician with OEM-level software.
Need broader troubleshooting steps? Explore the Dodge Dart check engine light overview or review the site-wide diagnostics guide for shared workflows and code charts.
When to Call a Professional
Seek professional help if the MIL flashes, if you detect metallic engine noises, or when MultiAir oil-pressure warnings accompany camshaft timing codes. A qualified technician can perform compression tests, oscilloscope diagnostics, and software updates that ensure the repair sticks.