Diagnostic trouble code generation, diagnostic trouble code/fault counter
|
|
Diagnostic trouble code generation, diagnostic trouble code/fault counter
|
For certain diagnostic trouble codes, the control module's fault handling subroutine also includes a fault counter in addition to assigning fault status. This applies to the diagnostic trouble codes which could cause the CHECK GEARBOX warning lamp to come on. During a drive cycle in which the control module's fault handling subroutine decides that a fault exists, the fault counter is set at 40 and the CHECK ENGINE and CHECK GEARBOX warning lamps come on. If the fault is self-repairing, i.e. during the following drive cycles the control module decides that no fault exists, the fault counter counts down at the rate of 1 unit per drive cycle. A drive cycle is initiated when the ignition key is turned to ON and ends when it is turned to OFF. When the fault counter reaches 37 the CHECK ENGINE and CHECK GEARBOX lamps go out but the diagnostic trouble code still remains stored. When the fault counter reaches 0 the diagnostic trouble code disappears. Diagnostic trouble codes that do not have a fault counter will remain stored until they are reset to zero, i.e. until they are erased with the diagnostics instrument command "CLEAR FAULT CODES".
