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System Test Mode

NOTE: SYSTEM TEST mode consists of a stationary test and a road test. The SYSTEM TEST mode must be selected from AW4 MENU. See ENTERING AW4 MENU under RETRIEVING DIAGNOSTIC TROUBLE CODES  .
  1. Stationary test monitors transmission system data, current valve body solenoid failures, switch failures, correct TCM application, calibration and operation. Road test checks all valve body solenoids and speed sensor.
  2. Technician will be instructed to place shift lever in each gear position, starting by shifting into 1-2 position. Once transmission is in Park, brake pedal must be depressed to check brake switch.
  3. After brake switch is checked, technician will be instructed to slowly depress throttle. DRB-II will display 7 asterisks (*******) corresponding to throttle position. While depressing accelerator, Throttle Position Sensor (TPS) sweeps through entire range of positions required by the TCM.
  4. A corresponding asterisk will be cleared from DRB-II display as each throttle position is sensed by TCM. Several attempts may be required to clear all asterisks from the display, depending on how fast accelerator is depressed.
  5. After throttle position is checked, technician will be instructed to drive the vehicle. The DRB-II will indicate if a requested action is seen by the TCM. If technician is requested to perform a particular operation and TCM does not acknowledge the action, press ENTER key to continue testing.
  6. The TCM will instruct technician to accelerate vehicle at light throttle to ensure transmission shifts through all gears, indicating proper valve body solenoid operation.
  7. During road test, ensure vehicle can be accelerated slowly and evenly to allow transmission to enter all gear ranges without downshifting or braking. If a failure is sensed, a diagnostic trouble code will be displayed on DRB-II.
NOTE: If TCM senses a failure, control logic activates a specified valve body solenoid to obtain a certain gear depending on failure. Because transmission diagnostic trouble codes are displayed one at a time, multiple diagnostic trouble codes must be identified by retesting transmission.
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