LAUNCH
3001
User’s Manual
19
The computer sets a Pending DTC, but the MIL is not ordered “On.” “Freeze
Frame” data may or may not be saved at this time depending on manufacturer.
The Pending DTC is saved in the computer’s memory for later retrieval.
If the failure is found on the second consecutive trip, the MIL is ordered “On.”
“Freeze Frame” data is saved in the computer’s memory.
If the failure is not found on the second Trip, the Pending DTC is erased from
the computer’s memory.
The MIL will stay lit for both Type “A” and Type “B” codes until one of the following
conditions occurs:
If the conditions that caused the MIL to light are no longer present for the next
three trips in a row, the computer automatically turns the MIL “Off” if no other
emissions-related faults are present. However, the DTCs remain in the
computer’s memory as a history code for 40 warm-up cycles (80 warm-up
cycles for fuel and misfire faults). The DTCs are automatically erased if the
fault that caused them to be set is not detected again during that period.
Misfire and fuel system faults require three trips with “similar conditions” before
the MIL is turned “Off.” These are trips where the engine load, RPM and
temperature are similar to the conditions present when the fault was first
found.
*Note: After the MIL has been turned off, DTCs and Freeze Frame data stay in the
computer’s memory.
Erasing the DTCs from the computer’s memory can also turn off the MIL. If a
Diagnostic Tool or Scan Tool is used to erase the codes, Freeze Frame data
will also be erased.