Enhanced Starter Motor Control Module Fault
2018-2018 Lincoln MKX 3.7L V6
The 2018 Lincoln MKX is equipped with a 3.7L V6 engine. Below you'll find detailed p3603 diagnostic code information including labor time estimates, cost ranges, and technician notes specific to this engine configuration.
Description
The enhanced or reinforced starter motor used in start-stop systems has a control module fault. These starters are designed for frequent cycling.
Symptoms
- Start-stop disabled
- Slow cranking after stop event
- Starter noise during restart
- Unusual vibration during start
- Increased restart time
Common Causes
- Starter control module failure
- Starter motor brush wear
- Pinion gear engagement issue
- Starter solenoid degradation
- Excessive starter motor temperature
Diagnostic Steps
- Read starter motor cycle count
- Test starter motor current draw
- Check starter engagement speed
- Monitor starter solenoid operation
- Measure voltage drop across starter circuit
Repair Notes
Replace enhanced starter motor assembly. Standard starters are not suitable for start-stop equipped vehicles.
Related Codes
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
P3603 on Other Vehicles
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2020-2020 3.0L Twin-Turbo V6
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2020-2020 3.0L V6 Twin Turbo
Lincoln Aviator
2020-2020 3.0L V6 Twin Turbo Hybrid
Lincoln Aviator
2021-2021 3.0L Twin-Turbo V6
Lincoln Aviator
2021-2021 3.0L V6 Twin Turbo
Lincoln Aviator
2021-2021 3.0L V6 Twin Turbo Hybrid
Lincoln Aviator
2022-2022 3.0L Twin-Turbo V6
Lincoln Aviator
2022-2022 3.0L V6 Twin Turbo
Common Questions
What does code P3603 mean on a 2018-2018 Lincoln MKX?
P3603 stands for "Enhanced Starter Motor Control Module Fault". The enhanced or reinforced starter motor used in start-stop systems has a control module fault. These starters are designed for frequent cycling.
What are the symptoms of P3603 on a Lincoln MKX?
Common symptoms of P3603 include: Start-stop disabled, Slow cranking after stop event, Starter noise during restart, Unusual vibration during start, Increased restart time.
What causes P3603 on a 2018-2018 Lincoln MKX?
Common causes of P3603 include: Starter control module failure, Starter motor brush wear, Pinion gear engagement issue, Starter solenoid degradation, Excessive starter motor temperature.
Last updated: March 2026