Trip Indicator
The Trip is essential for running monitors and extinguishing MIL. In OBD II terms, a trip is a set of vehicle operating conditions that must be met for a specific monitor to run. All trips begin with a key cycle.
Good Trip
The Good Trip counters are as follows:
- Global Good Trip
- Fuel System Good Trip
- Misfire Good Trip
- Alternate Good Trip (appears as a Global Good Trip on DRBIII(R))
- Comprehensive Components
- Major Monitor
- Warm-Up Cycles
Global Good Trip
To increment a Global Good Trip, Oxygen sensor and Catalyst efficiency monitors must have run and passed 2 minutes of engine run time.
Fuel System Good Trip
To count a good trip (3 required) and turn off MIL, the following conditions must occur:
- Engine in closed loop.
- Operating in Similar Conditions Window.
- Short Term multiplied by Long Term less than threshold.
- Less than threshold for a predetermined time.
If all of previous criteria are met, PCM will count a good trip (3 required) and turn off MIL.
Misfire Good Trip
If the following conditions are met PCM will count 1 good trip (3 required) in order to turn off MIL:
- Operating in Similar Condition Window.
- 1000 engine revolutions with no misfire.
Alternate Good Trip
Alternate Good Trips are used in place of Global Good Trips for Comprehensive Components and Major Monitors. If Task Manager cannot run a Global Good Trip because a component fault is stopping monitor from running, it will attempt to count an Alternate Good Trip.
The Task Manager counts an Alternate Good Trip for Comprehensive components when the following conditions are met:
- 2 minutes of engine run time, idle or driving.
- No other faults occur.
The Task Manager counts an Alternate Good Trip for a Major Monitor when monitor runs and passes. Only Major Monitor that failed needs to pass to count an Alternate Good Trip.
Warm-Up Cycles
Once MIL has been extinguished by Good Trip Counter, PCM automatically switches to a Warm-Up Cycle Counter that can be viewed on DRBIII(R). Warm-Up Cycles are used to erase DTCs and Freeze Frames. 40 Warm-Up cycles must occur in order for PCM to self-erase a DTC and Freeze Frame. A Warm-Up Cycle is defined as follows:
- Engine coolant temperature must start below and rise above 160°F.
- Engine coolant temperature must rise by 40°F.
- No further faults occur.