As a content creator for carscanner.store and an automotive repair expert, I often encounter questions about vehicle readiness for emissions testing. A common scenario involves using a car scanner tool and seeing a “Not Ready” status. This article will delve into what “Not Ready” means, particularly in the context of Chrysler vehicles and their drive cycles, and how you can use your car scanner effectively to ensure your vehicle is ready for its emissions test.
Understanding OBD-II Monitors and Readiness
Modern vehicles are equipped with On-Board Diagnostics II (OBD-II) systems that monitor various engine and emission control components. These systems run self-tests, known as monitors, to ensure everything is functioning correctly and within emission standards. These monitors cover systems like:
- Catalyst Monitor: Checks the efficiency of the catalytic converter.
- EGR System Monitor: Evaluates the Exhaust Gas Recirculation system.
- Evaporative System Monitor: Tests for fuel vapor leaks in the EVAP system.
- O2 Sensor Monitor: Monitors the oxygen sensors.
- O2 Sensor Heater Monitor: Checks the functionality of the oxygen sensor heaters.
When these monitors have successfully completed their tests, they are considered “ready.” However, after certain events like a battery disconnection, clearing diagnostic trouble codes (DTCs), or some repairs, these monitors are reset to a “not ready” state. Your vehicle needs to complete a specific driving pattern, known as a “drive cycle,” to allow these monitors to run and reset to “ready.”
Why “Not Ready” Matters for Emissions Testing
Most emissions testing centers require a certain number of monitors to be in a “ready” state to pass the test. If your car scanner tool indicates “Not Ready” for too many monitors, your vehicle will likely fail the emissions test, even if there are no active DTCs or the check engine light is off. This is because the “Not Ready” status signals that the OBD-II system hasn’t fully verified the emission control systems since the last reset.
Chrysler Drive Cycles: Your Key to Readiness
Chrysler, like other manufacturers, has specific drive cycle procedures designed to set the readiness monitors. While you don’t need to drive a specific distance, you absolutely need to follow a specific drive cycle. Here are some Chrysler drive cycle examples to address different monitors. It’s important to note that these are general guidelines, and you should always consult your vehicle’s service manual for the most accurate and model-specific drive cycle.
General Chrysler Drive Cycle
This drive cycle aims to set multiple monitors.
Pre-Conditioning Requirements:
- MIL (Malfunction Indicator Lamp – Check Engine Light) must be off.
- Cold start (engine hasn’t been run for several hours).
Driving Procedure:
- Warm engine up for five minutes (ensure it reaches closed loop operation – normal operating temperature).
- Drive at a steady speed between 40 and 60 mph for 8 minutes.
- Stop and idle for 3 minutes.
- Drive at a steady speed above 20 mph for 2 minutes.
- Turn the ignition key off and leave it off for ten minutes. This step is crucial for the O2 sensor heater monitor.
Alt text: Modern car engine bay showcasing various components, relevant to understanding car diagnostics and emission systems.
Catalyst Monitor Drive Cycle
This cycle specifically targets the catalyst monitor.
Pre-Conditioning Requirements:
- MIL must be off.
- No DTCs present.
- Fuel level between 15% and 85% full.
- Engine Coolant Temperature (ECT) above 70º F.
- Engine must have run for at least 90 seconds.
- Engine RPM between 1,350 & 1,900 rpm.
Driving Procedure:
- Idle vehicle for five minutes to reach closed loop operation.
- Drive at a steady speed between 30 and 45 mph for 2 minutes.
EGR System Monitor Drive Cycle (Vacuum Controlled)
This is for EGR systems controlled by vacuum.
Pre-Conditioning Requirements:
- MIL must be off.
Driving Procedure:
- Idle vehicle for five minutes to reach closed loop operation.
- Drive at a steady speed between 40 & 60 mph for 8 minutes.
EGR System Monitor Drive Cycle (Electronic)
This cycle applies to electronically controlled EGR systems.
Pre-Conditioning Requirements:
- MIL must be off.
- Manifold Absolute Pressure (MAP) between 0-60 KPa.
- Engine speed between 500-850 rpm.
- ECT above 180º F (90º C).
- No misfire temporary (pending) or matured fault present.
- A/C clutch, Power Steering (PS) Switch, and Cooling fans should not change state (turn off).
Driving Procedure:
- Idle vehicle for five (5) minutes to reach closed loop operation.
- Drive at a steady speed between 40 & 60 mph for 2 minutes.
- Idle vehicle for three (3) minutes.
Alt text: Car dashboard with the check engine light on, indicating potential issues detectable by a car scanner tool.
Evaporative System Monitor Drive Cycle
Chrysler has different traces for the EVAP system.
Trace 1: Standard Type
Pre-Conditioning Requirements:
- MIL must be off.
- No Evaporative DTCs present.
- Fuel level between ½ and full (can sometimes run between 15% and 85%).
Driving Procedure:
- Idle vehicle for five minutes to reach closed loop operation.
- Drive at a steady speed between 30 and 45 mph for 2 minutes.
Trace 2: Leak Detection Pump
Pre-Conditioning Requirements:
- MIL must be off.
- No Evaporative DTCs present.
- Fuel level between 30 & 85 % full.
Driving Procedure:
- Cold soak vehicle (allow it to cool down completely), start, and idle for 4 minutes.
- Drive in-town (stop and go) for 5 minutes with smooth accelerations and decelerations.
- Stop and idle for 4 minutes.
O2 Sensor Monitor Drive Cycle
For setting the Oxygen sensor monitor.
Pre-Conditioning Requirements:
- MIL must be off.
Driving Procedure:
- Idle vehicle for five minutes to reach closed loop operation.
- Drive at a steady speed above 25 mph for 2 minutes.
- Stop and idle for 30 seconds.
- Smoothly accelerate to a speed between 30 and 40 mph.
- Repeat steps 3 & 4 five (5) times.
O2 Sensor Heater Monitor Drive Cycle
Specifically for the O2 sensor heater monitor.
Pre-Conditioning Requirements:
- MIL must be off.
Driving Procedure:
- Idle vehicle for five minutes to reach closed loop operation.
- Shut engine off and leave vehicle off for ten minutes.
Using Your Car Scanner Tool to Verify Readiness
After performing a drive cycle, use your car scanner tool to check the status of the OBD-II monitors. Connect your scanner to your vehicle’s OBD-II port and navigate to the “Readiness Monitors” or “I/M Readiness” section. Your scanner will display the status of each monitor, indicating whether they are “Ready” or “Not Ready.”
If, after performing the appropriate drive cycles, you still see “Not Ready” statuses, there could be underlying issues preventing the monitors from setting. In such cases, further diagnosis with your car scanner, looking for pending DTCs, or seeking professional automotive service is recommended.
Conclusion
Understanding Chrysler drive cycles and utilizing your car scanner tool to check OBD-II monitor readiness is crucial for ensuring your vehicle passes emissions testing. By following these procedures and correctly interpreting your car scanner’s readings, you can confidently approach your emissions test and address any “Not Ready” issues proactively. Remember to consult your vehicle’s repair manual for the most accurate drive cycle information and always prioritize safety when performing drive cycles.
