Inspection and Verification - AWD
Note. If the area of concern is indicated to be other than the transfer case, refer to the appropriate article.
- Road test the vehicle to verify the concern, noting the road speed, engine speed, and speed range where the vehicle problem is evident.
- Raise the vehicle on the hoist and position suitable safety floor stands under the vehicle.
- Run the vehicle at the road speed where the concern exists. Verify the concern: engine transmission front/rear driveline components front/rear drive axles front/rear brake systems front/rear wheels or tires transfer case
- Refer to the appropriate owner literature for operating data. Verify the concern as driveline or torsional windup before repairing the transfer case.
- Check the tires and vehicle load if the problem is clearly driveline windup and not broken parts.
- If the concern is not visually evident, refer to the «SYMPTOM CHART - AWD»(ref-194050-S14054075772005092600000) .
Symptom Chart - AWD
| Condition | Possible Sources | Action |
|---|---|---|
| The transfer case makes noise | Tire inflation pressure. Tire and wheel size. | MAKE SURE that all tires and wheels are the same size and that the inflation pressures are correct. |
| Tire tread wear. | CHECK tire tread wear to see if there is more than 0.15 mm (0.006 in) difference in tread wear between front and rear. INTERCHANGE one front wheel and one rear wheel. Road test again. | |
| Internal components. | OPERATE the vehicle in all transmission gears. If there is noise in the transmission in NEUTRAL, or in some gears and not in others, REMOVE and REPAIR the transmission. REFER to AUTOMATIC TRANSAXLE/TRANSMISSION . If there is noise in all gears, DISASSEMBLE the transfer case. REFER to TRANSFER CASE - AWD . CHECK the planetary gears, the bearings, the upper and lower drive sprockets and drive chain for damage. INSTALL new parts as necessary. | |
| Fluid level. | FILL with automatic transmission fluid. REFER to TRANSFER CASE DRAINING AND FILLING . | |
| Transfer case makes noise/shudder - vehicles in Auto mode may exhibit shudder/noise from the front driveline, occurs on acceleration while driving. All vehicles may exhibit axle windup or binding while driving. Some manual and electric shift vehicles with a 4x2 mode may not shift on the fly or into 4x4 Auto or high at highway speeds. | Incorrect tire circumference. Tires are not inflated to the proper tire pressure. | VERIFY all tires and wheels are the same size. CHECK the tire for the correct inflation pressure. VERIFY that all four tires have no more than 6.350 mm (0.25 in) variation in circumference. CORRECT as necessary. |
| Wheel/tire bounce, vehicle skip | Internal components. | OPERATE the vehicle in all transmission gears. If there is noise in the transmission in NEUTRAL, or in some gears and not in others, REMOVE and REPAIR the transmission. REFER to AUTOMATIC TRANSAXLE/TRANSMISSION . If there is noise in all gears, DISASSEMBLE the transfer case. REFER to TRANSFER CASE - AWD . CHECK the planetary gears, the bearings, the upper and lower drive sprockets and drive chain for damage. INSTALL new parts as necessary. |
| Tire tread wear. | MAKE SURE that all tires and wheels are the same size and that inflation pressures are correct. REFER to SUSPENSION SYSTEM . | |
| Leaking automatic transmission fluid (ATF) from vent | Transfer case. | DRAIN the fluid to the correct level. REFER to TRANSFER CASE DRAINING AND FILLING . |
| Vent tube. | REPAIR or INSTALL a new vent tube. REFER to TRANSFER CASE . | |
| Leaking automatic transmission fluid (ATF) from transfer case housing | Transfer case housing bolts. | TIGHTEN the bolts to specification. REFER to SPECIFICATIONS . |
| Sealant. | REBUILD with black non-acid cure silicone gasket and sealant. REFER to TRANSFER CASE - AWD . | |
| Fluid. | DRAIN fluid and FILL with automatic transmission fluid. REFER to TRANSFER CASE DRAINING AND FILLING . | |
| Transfer case gasket. | INSTALL a new transfer case gasket. REFER to TRANSFER CASE . | |
| Leaking automatic transmission fluid (ATF) output shaft seals | The vent is plugged. | REPAIR the plugged vent. |
| Output shaft seals. | INSTALL a new output shaft seal. REFER to TRANSFER CASE . | |
| The front axle does not engage correctly | Front axle. | REFER to DRIVELINE SYSTEM . |
| Transfer case clutch. Internal components. | DISASSEMBLE the transfer case. REFER to TRANSFER CASE - AWD . CHECK the planetary gears, the bearings, the upper and lower drive sprockets and drive chain for damage. INSTALL new parts as necessary. |
SYMPTOM CHART - AWD
Scheme 4
- Verify the customer concern.
- Visually inspect for obvious signs of mechanical or electrical damage.
- If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
- If the concern is not visually evident, connect the diagnostic tool to the data link connector and select the vehicle to be tested from the diagnostic tool menu. If the diagnostic tool does not communicate with the vehicle: check that the program card is correctly installed. check the connections to the vehicle. check the ignition switch position.
- If the diagnostic tool still does not communicate with the vehicle, refer to Diagnostic tool operating manual.
- Carry out the diagnostic tool data link test. If the diagnostic tool responds with: SCP+, SCP-, UBP or ISO circuit fault; all electronic control units no response/not equipped, refer to «MODULE COMMUNICATIONS NETWORK»(ref-194061) . No response/not equipped for 4WD control module, GO to Pinpoint Test B. System passed, retrieve and record the continuous diagnostic trouble codes (DTCs), erase the continuous DTCs and carry out the 4WD control module self- test.
- If the DTCs retrieved are related to the concern, go to the 4WD Control Module Diagnostic Trouble Code (DTC) Index - Electronic Shift to continue diagnostics.
4WD Control Module Diagnostic Trouble Code (DTC) Index - Electronic Shift
| DTC | Description | Source | Action |
|---|---|---|---|
| B1317 | Battery Voltage High | 4WD control module | REFER to BATTERY AND CHARGING SYSTEM Section 414-00 . |
| B1318 | Battery Voltage Low | 4WD control module | REFER to BATTERY AND CHARGING SYSTEM . |
| B1342 | ECU is Defective | 4WD control module | CLEAR the DTCs. REPEAT the 4WD control module self-test. If DTC B1342 is retrieved, INSTALL a new 4WD control module. REFER to FOUR-WHEEL DRIVE (4WD) CONTROL MODULE . CLEAR the DTCs. REPEAT the self-test. |
| B1483 | Brake Pedal Input Circuit Failure | 4WD control module | Go To PINPOINT TEST C . |
| B1485 | Brake Pedal Input Short to Battery | 4WD control module | Go To PINPOINT TEST C . |
| B2105 | Throttle Position Input Out of Range Low | 4WD control module | Go To PINPOINT TEST A . |
| B2106 | Throttle Position Input Out of Range High | 4WD control module | Go To PINPOINT TEST A . |
| C1729 | Transfer Case Unable to Transition Between 4WD HIGH and 4WD LOW | 4WD control module | Go To PINPOINT TEST C . |
| C1970 | 4WD Low Mode Switch LED Short to Battery | 4WD control module | Go To PINPOINT TEST C . |
| C1971 | 4WD Low Mode Switch LED Circuit Failure | 4WD control module | Go To PINPOINT TEST C . |
| P1707 | Transfer Case Neutral Indicator Hard Fault Present | 4WD control module | Go To PINPOINT TEST C . |
| P1812 | Transmission 4-Wheel Drive Mode Select Circuit Failure | 4WD control module | Go To PINPOINT TEST A . |
| P1815 | Transmission 4-Wheel Drive Mode Select Short Circuit to Ground | 4WD control module | Go To PINPOINT TEST A . |
| P1816 | Transmission NEUTRAL Safety Switch Circuit Failure | 4WD control module | Go To PINPOINT TEST C . |
| P1819 | Transmission NEUTRAL Safety Switch Circuit Short to Ground | 4WD control module | Go To PINPOINT TEST C . |
| P1824 | Transmission 4-Wheel Drive Clutch Relay Circuit Failure | 4WD control module | Go To PINPOINT TEST A . |
| P1826 | Transmission 4-Wheel Drive Low Clutch Relay Short Circuit to Battery | 4WD control module | Go To PINPOINT TEST A . |
| P1827 | Transmission 4-Wheel Drive Low Clutch Relay Short Circuit to Ground | 4WD control module | Go To PINPOINT TEST A . |
| P1836 | Transmission Transfer Case Front Shaft Speed Sensor Circuit Failure | 4WD control module | Go To PINPOINT TEST A . |
| P1837 | Transmission Transfer Case Rear Shaft Speed Sensor Circuit Failure | 4WD control module | Go To PINPOINT TEST A . |
| P1849 | Transmission Transfer Case Contact Plate A Short Circuit to Ground | 4WD control module | Go To PINPOINT TEST C . |
| P1853 | Transmission Transfer Case Contact Plate B Short Circuit to Ground | 4WD control module | Go To PINPOINT TEST C . |
| P1857 | Transmission Transfer Case Contact Plate C Short Circuit to Ground | 4WD control module | Go To PINPOINT TEST C . |
| P1861 | Transmission Transfer Case Contact Plate D Short Circuit to Ground | 4WD control module | Go To PINPOINT TEST C . |
| P1867 | Transmission Transfer Case Contact Plate General Circuit Failure | 4WD control module | Go To PINPOINT TEST C . |
| P1874 | Transmission Automatic Hall Effect Sensor Power Circuit Failure | 4WD control module | Go To PINPOINT TEST A . |
| P1875 | Transmission Automatic Hall Effect Sensor Power Circuit Short to Battery | 4WD control module | Go To PINPOINT TEST A . |
| P1891 | Transmission Transfer Case Contact Plate Ground Return Open Circuit | 4WD control module | Go To PINPOINT TEST C . |
| U1900 | CAN Communication BUS Fault | 4WD control module | REFER to MODULE COMMUNICATIONS NETWORK . |
| U1950 | USB Communication BUS Fault | 4WD control module | REFER to MODULE COMMUNICATIONS NETWORK . |
| U2023 | External Node Fault | 4WD control module | REFER to MODULE COMMUNICATIONS NETWORK . |
| U2226 | Invalid UBP Data From PCM (Node 10) | 4WD control module | REFER to MODULE COMMUNICATIONS NETWORK . |
| U2306 | Invalid UBP Data From Instrument Cluster (Node 60) | 4WD control module | REFER to MODULE COMMUNICATIONS NETWORK . |
| For All Other DTCs | 4WD control module | REFER to MODULE COMMUNICATIONS NETWORK . |
4WD CONTROL MODULE DIAGNOSTIC TROUBLE CODE (DTC) INDEX - ELECTRONIC SHIFT
Symptom Chart - Electronic Shift
| Condition | Possible Sources | Action |
|---|---|---|
| The vehicle does not operate correctly in 4x4 Auto and 4x4 High modes | Battery junction box (BJB) fuses: 17 (20A). 18 (20A). Central junction box (CJB) fuse 12 (5A). Mode select switch (MSS). Transfer case shaft speed sensors. Transfer case electric clutch. Four-wheel drive (4WD) control module. Powertrain control module (PCM). Stability assist. Circuitry. | Go To PINPOINT TEST A . |
| No communication with the four-wheel drive (4WD) control module - Electronic Shift | Battery junction box (BJB) fuses: 17 (20A). 18 (20A). Central junction box (CJB) fuse 12 (5A). Four-wheel drive (4WD) control module. Four-wheel drive (4WD) control module connectors. Circuitry. | Go To PINPOINT TEST B . |
| The vehicle does not shift between 4x4 High and 4x4 Low modes correctly | Battery junction box (BJB) fuses: 17 (20A). 18 (20A). Central junction box (CJB) fuse 12 (5A). Mode select switch (MSS). Gearmotor encoder contact plate A, B, C, or D. Gearmotor encoder contact plate A, B, C, or D. Gearmotor encoder assembly. Circuitry. Four-wheel drive (4WD) control module. Transfer case internal mechanism. Transfer case shift motor. Digital transmission range (TR) sensor. Brake pedal position (BPP) switch. Stability assist. Four-wheel anti-lock brake system (4WABS) control module. Instrument cluster (manual transmission only). | Go To PINPOINT TEST C . |
SYMPTOM CHART - ELECTRONIC SHIFT
