Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2021 Lincoln Navigator Base, 4WDFACTORY OEM SERVICE PROCEDURE
Four-Wheel Drive Systems
- Description And Operation
- Diagnosis And Testing
- Four-Wheel Drive Systems - Vehicles With: 1-Speed Torque On Demand Transfer Case
- DTC Chart: TCCM
- Symptom Charts
- Pinpoint Tests
- Pinpoint Test A: Four-Wheel Drive (4WD) System Functional Test
- Pinpoint Test B: DTC (Diagnostic Trouble Code) U300D:11
- Pinpoint Test C: DTC (Diagnostic Trouble Code): P0562:00, P0563:00
- Pinpoint Test D: DTC (Diagnostic Trouble Code): C1979:11, C1979:12, C1979:13 IWE (Integrated Wheel End) Solenoid - Electrical Fault
- Pinpoint Test E: The Front Axle Does Not Engage/Disengage Correctly
- Pinpoint Test F: Four-Wheel Drive (4WD) Clutch Field Coil - Electrical
- Pinpoint Test G: U0100:00
- Pinpoint Test H: DTC (Diagnostic Trouble Code) U0101:00
- Pinpoint Test I: U0138:00
- Pinpoint Test J: U0140:00
- Pinpoint Test K: U0121:00
- Pinpoint Test L: U0140:00
- Pinpoint Test M: Grinding / Clicking / Ratcheting Noise From Front Axle In 2H Mode Under Acceleration Or Heavy Loads
- Pinpoint Test N: U0418:00
- Pinpoint Test O: U0439:00
- Pinpoint Test P: U2300:54
- Pinpoint Test Q: U2300:55
- Pinpoint Test R: U2300:56
- Pinpoint Test S: U2300:64
- Pinpoint Test T: U3000:04
- Pinpoint Test U: U3000:46
- Pinpoint Test V: DTC: U3000:49
- Pinpoint Test W: DTC: U2009:9E
- Pinpoint Test X: DTC: U2002:9E
- Pinpoint Test Y: DTC: P06B8:00
- Four-Wheel Drive Systems - Vehicles With: 2-Speed Torque On Demand Transfer Case
- DTC Chart: TCCM
- Symptom Charts
- Pinpoint Tests
- Pinpoint Test A: Four-Wheel Drive (4WD) System Functional Test
- Pinpoint Test B: DTC U300D:11
- Pinpoint Test C: DTC P0562:00, P0563:00
- Pinpoint Test D: DTC (Diagnostic Trouble Code): C1979:11, C1979:12, C1979:13 IWE (Integrated Wheel End) Solenoid - Electrical Fault
- Pinpoint Test E: The Front Axle Does Not Engage/Disengage Correctly
- Pinpoint Test F: 4WD (Four-Wheel Drive) Clutch Field Coil - Electrical
- Pinpoint Test G: Shift Motor - Electrical Or Mechanical Fault
- Pinpoint Test H: Lost Communication With Suspect Module
- Pinpoint Test I: Grinding / Clicking / Ratcheting Noise From Front Axle In 2H Mode Under Acceleration Or Heavy Loads
- Pinpoint Test J: U0418:00
- Pinpoint Test K: U0439:00
- Pinpoint Test L: U2300:54
- Pinpoint Test M: U2300:55
- Pinpoint Test N: U2300:56
- Pinpoint Test O: U2300:64
- Pinpoint Test P: U3000:04
- Pinpoint Test Q: U3000:46
- Pinpoint Test R: DTC: U3000:49
- Pinpoint Test S: DTC: U3000:49
- Pinpoint Test T: DTC: U2009:9E
- Pinpoint Test U: DTC: U2002:9E
- Pinpoint Test V: DTC: P06B8:00
- Pinpoint Test W: U0140:00
- Four-Wheel Drive Systems - Vehicles With: 1-Speed Torque On Demand Transfer Case
- General Procedures
- Removal And Installation
Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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