Jeep Cherokee

 Service Manual

Transmission and transfer case » AW-4 automatic transmission » Diagnosis and testing
Manual shifting test

(1) This test determines if problem is related to mechanical or electrical component.

(2) Stop engine and disconnect transmission control module or module fuse.

(3) Road test vehicle. Shift transmission into each gear range. Transmission should operate as follows:

•  lock in Park
•  back up in Reverse
•  not move in Neutral
•  provide first gear only with shift lever in 1-2 position
•  operate in third gear only with shift lever in 3 position
•  operate in overdrive fourth gear in D position

(4) If transmission operates as described, proceed to next step. However, if forward gear ranges were difficult to distinguish (all feel the same), or vehicle would not back up, refer to diagnosis charts. Do not perform stall or time lag tests.

CAUTION: Do not over speed the engine during the next test step. Ease off the throttle and allow the vehicle to slow before downshifting.

(5) Continue road test. Manually downshift transmission from D to 3, and from 3 to 1-2 position.

Then manually upshift transmission through forward ranges again.

(6) If transmission operation is OK, perform stall, time lag and pressure tests. If transmission shifting problem is encountered, refer to diagnosis charts.

(7) If a problem still exists, continue testing with DRB scan tool.

General diagnosis information

Effects of incorrect fluid level

Causes of burnt fluid

Fluid contamination

Preliminary inspection and adjustment

Manual shifting test

Hydraulic pressure test

Pressure test analysis

Time lag test

Test procedure

Time lag test analysis

Service diagnosis

Transmission solenoid testing

Park/neutral position switch

Gearshift cable

Throttle valve cable

Speed sensor testing

Flow testing transmission main cooler

Torque converter stator clutch inspection