Code 5

Start vehicle and observe Yellow light for proper self-check. If Yellow light self-check is okay, go to next step. If Yellow light self-check is not okay, go to TEST A - YELLOW LIGHT OFF, DOES NOT SELF-CHECK under PRECHECK TESTS .
Disconnect control module connector. Drive vehicle at approximately 20 MPH. Perform a light to medium normal traffic stop. If rear wheels lock-up, reconnect control module. Diagnose foundation brake system for cause of rear wheel lock-up. If rear wheels do not lock-up, reconnect control module and go to next step.
Drive vehicle approximately 10 MPH on dry pavement. Depress brake pedal hard enough to lock all 4 wheels while observing left rear wheel in drivers mirror. If rear wheels locked-up, replace valve assembly. Go to CODE 16 under TEST DRIVE . If rear wheels did not lock-up, go to next step.
Raise vehicle on hoist to allow wheels to spin freely. Ensure vehicle is in 2WD mode and hubs are unlocked. Start vehicle and place transmission in Drive. Allow wheels to spin at 10 MPH. Apply brake pedal hard until wheels stop. If rear wheels first lock-up then spin, leave ignition on and go to next step. If wheels react normally, go to next step.
Check for trouble codes. See RETRIEVING TROUBLE CODES . If Code 5 is present, result is inconsistent. Clear codes. Repeat step 4). If result repeats or Code 16 is present, return to step 6) in CODE 5 - EXCESSIVE DUMP SOLENOID ACTIVITY under TROUBLE CODE DIAGNOSIS . If a different code is present, refer to the corresponding code under TROUBLE CODE DIAGNOSIS . If no codes are present, go to TEST D - YELLOW LIGHT CHECK OKAY, BUT DOESN'T FLASH TROUBLE CODE under PRECHECK TESTS .

NOTE: Following test is designed to resolve a Code 6 condition. Performing test for any other reason may lead to incorrect diagnosis.