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Clearing Diagnostic Trouble Codes




To clear trouble codes proceed as follows:

1. Enter diagnostics.

2. Select code by system type. After all codes have been displayed and you have decided which control system code (ECM/PCM or BCM) by pressing the "FAN UP" after the "EC?" or "BC?" message is displayed. If you only want to clear BCM codes, you must press "FAN DOWN" after the "EC?" message, since it is displayed first. This process will access the specific system in which you wish to clear codes.

3. Select "CLEAR CODES." After accessing the appropriate system, either ECM/PCM or BCM, test mode messages will be displayed and you must respond by repeatedly pressing the "FAN DOWN" until the "CLR E CODE?" or "CLR B CODE?" message is displayed for the system you accessed. Next, press the "FAN UP" which will result in an "E CODE CLR" or "B CODE CLR" message. Now, press "BI-LEVEL" to exit diagnostics and then re-enter diagnostics to verify if the trouble codes were cleared.

Selection of the "CLEAR CODES?" test type will result in either the message "CODES CLEAR" or "CODES/X NOT CLEAR" being displayed, indicating wether the codes were successfully cleared. This message will appear for 3.0 seconds to indicate that all stored trouble codes have been erased from that systems memory. After 3.0 seconds the display will automatically return to the next available test type for the selected system.

NOTE: SIR code 51 cannot be cleared without the use of an ALDL scan tool. Refer to "SIR TROUBLE CODE CHARTS" under COMPUTERIZED ENGINE CONTROLS/DIAGNOSIS AND TESTING PROCEDURES/TESTING PROCEDURES/DIAGNOSTIC CHARTS.