Component Tests and General Diagnostics

NOTE: The transmission linkage/cable adjustment, fluid level and line pressure must be within specification before performing this test.

1. Remove the fluid level indicator from the fluid filler tube.
2. Place a funnel in the fluid filler tube.
3. Raise and support the vehicle.

WARNING: THE ELECTRICAL POWER TO THE AIR SUSPENSION SYSTEM MUST BE SHUT OFF PRIOR TO HOISTING, JACKING OR TOWING AN AIR SUSPENSION VEHICLE. THIS CAN BE ACCOMPLISHED BY TURNING OFF THE AIR SUSPENSION SWITCH LOCATED IN THE RH KICK PANEL AREA. FAILURE TO DO SO MAY RESULT IN UNEXPECTED INFLATION OR DEFLATION OF THE AIR SPRINGS WHICH MAY RESULT IN SHIFTING OF THE VEHICLE DURING THESE OPERATIONS.

4. Disconnect the cooler return tube (rear fitting) from the transmission cooler bypass valve (CBV).
5. Connect one end of a hose to the cooler return tube and route the other end of the hose up to a point where it can be inserted into the funnel at the fluid filler tube.
6. Remove the supports and lower the vehicle.

NOTE: If equipped with air suspension, reactivate the system by turning on the air suspension switch.

7. Insert the end of a hose into the funnel.
8. Start the engine and run at idle with the transmission in the neutral range.
9. When the fluid flowing from the hose is all liquid, an adequate amount of fluid should be observed, approximately 1.0 L (1.057 quarts) delivered in 30 seconds. If adequate flow is observed, the test is completed.
10. If the flow is not adequate, stop the engine. Disconnect the hose from the cooler return tube and connect it to the converter-out tube fitting (front fitting at the transmission cooler bypass valve).
11. Repeat Steps 7 and 8. If the flow is now adequate, further diagnosis of the transmission fluid cooler. If the flow is not adequate, repair or replace the pump, the converter assembly, or both.