Symptom Chart - Four-Wheel Drive (4WD)

WARNING: This page is about a different variant/trim than selected.

SYMPTOM CHART

Condition	Possible Sources	Action
No communication with the Transfer Case Control Module (TCCM)	Scan tool Data Link Connector (DLC) TCCM Circuitry	REFER to MODULE COMMUNICATIONS NETWORK .
The 4X4 mode indicators do not operate correctly/do not operate	Instrument Cluster (IC) Four-Wheel Drive (4WD) system fault High Speed Controller Area Network (HS-CAN) TCCM Ignition switch and/or circuitry	GO to PINPOINT TEST V .
The vehicle does not shift between 2H (2WD) and 4X4 modes correctly	Mode Select Switch (MSS) Transfer case Transfer case clutch Integrated Wheel End (IWE) TCCM Circuitry	GO to PINPOINT TEST X .
The vehicle does not shift between 4A (4X4 AUTO) and 4H (4X4) modes correctly	MSS Transfer case Circuitry TCCM	GO to PINPOINT TEST O .
Vehicle has no torque or inadequate torque at front wheels in 4A (4X4 AUTO) mode	Transfer case Circuitry TCCM	CARRY OUT the Four-Wheel Drive (4WD) System Functional Test. GO to PINPOINT TEST U .
The vehicle does not shift between 4H (4X4) and 4L (4X4 LOW) modes correctly	Transfer case MSS TCCM Transmission drag torque	GO to PINPOINT TEST P .
Four-Wheel Drive (4WD) does not engage at speed correctly	Transfer case clutch coil TCCM IWEs	GO to PINPOINT TEST Q .
The front axle does not engage/disengage correctly	MSS IWEs IWE solenoid Vacuum leaks TCCM Front halfshaft Vacuum check valve(s)	GO to PINPOINT TEST N .
The Four-Wheel Drive (4WD) system jumps out of gear	Transfer case IWE vent MSS	GO to PINPOINT TEST R .
Unable to duplicate customer concern	4WD system and/or related components	CARRY OUT the Four-Wheel Drive (4WD) System Functional Test. GO to PINPOINT TEST U .