Selecting Test Mode

Five test modes are available for diagnosing ABS/TCS. Test modes are:

• Mode F0 (Data List) Mode continuously monitors wheel speed data, brake switch status, ABS/TCS status, and other inputs and outputs. Data list can not be read if any DTCs are set.
• Mode F1 (DTC History) ABS/TCS has no code history capabilities. If ANTI-LOCK and/or TRACTION OFF indicators are illuminated before entering diagnostics, at least one DTC is current. If ANTI-LOCK and/or TRACTION OFF indicators are not illuminated before entering diagnostics, no DTCs are current. When more than one DTC is stored and ANTI-LOCK and/or TRACTION OFF indicators are illuminated before entering diagnostics, it is impossible to determine between current and history DTCs.
• Mode F2 (Diagnostic Trouble Codes) Mode displays ABS/TCS diagnostic trouble codes. Tech 1 will display any DTCs and brief description of DTC displayed. If no DTC is stored, Tech 1 will display NO ABS CODES. Proceed to SYMPTOM DIAGNOSIS. Tech 1 will respond to a clear DTCs command by indicating ABS CODES CLEARED or CODE CLEAR FAIL.
• Mode F3 (Snapshot) Mode will help isolate intermittent problems by capturing data before and after fault condition. Snapshots cannot be read until all stored DTCs are cleared.

  If MANUAL TRIGGER is selected, Tech 1 will wait for ENTER to be pressed before storing data. Tech 1 stores data from 8 seconds before trigger and 8 seconds after trigger is activated. All stored information can be displayed and examined for conditions which might indicate a problem, but may not set a code.

  If AUTOMATIC TRIGGER is selected, Tech 1 will capture data which deviates from normal conditions but may not set a DTC, such as driving over bumpy roads or railroad tracks.Condition may be caused by loose connections or intermittent wiring problems causing signal to drop out momentarily. While Tech 1 is waiting for a trigger, ENTER or F9 key may be used to force a trigger.

• Mode F4 (ABS/TCS Tests) This mode is used to perform hydraulic modulator functional tests to assist in problem isolation. Tests cannot be performed until all stored DTCs are cleared. For more information, refer to scan tool operation manual.