A basic drive cycle is one of many methods your vehicle’s powertrain control module (PCM) verifies whether an emissions system repair was properly corrected. During various drive scenario’s the PCM runs a number of tests verifying if the monitors are in the readiness state. This helps to ensure the emissions system is working properly.
Purpose of a Drive Cycle
The Check Engine or Service Engine Soon Light is a way that your vehicle alerts you something isn’t correct. This can signal an emission system problem and this fault code will be recorded in the powertrain control module (PCM). The majority of time the only way to to address the code is to first diagnose the code and then perform some sort of repair.
After that, the PCM will run a series of self-tests this is to determine whether or not the repair actually corrected the problem. If the repair didn’t you will still have a fault code or you will have a new one.
The purpose of this process was designed to prevent a vehicle from slipping through an emissions test with a known problem.
Common reasons why you will need to perform a drive cycle
- You have replaced your battery
- You have updated or installed a tune in your car or truck
- Check engine light and/or emissions parts are replaced.
Learn how to Perform a Basic Drive Cycle
Below are steps to perform a basic drive cycle that will complete the readiness monitors for your vehicle’s emissions control system.
Step 1: How to Prepare Your Vehicle
- Have the fuel tank between 30 and 70 percent full.
- The vehicle must also have a good alternator and a strong battery.
- The vehicle must sit overnight, or for at least eight hours, in an environment that is less than 90° F.
- The keys must be out of the ignition and all of the doors must be closed while the vehicle sits over night.
Step 2: Cold Start
- Start the vehicle and let it idle for two to three minutes in Park or Neutral. While it is idling, turn on the head lights, heater/defroster, and rear defroster for a three to five minute warm-up phase. Let the idle speed settle down to near the normal speed.
- Next, put the vehicle in gear and drive through city streets at about 25 mph. Go up to about 35 to 40 mph a few times before slowing down to stop.
Step 3: A Short Freeway Trip
- After the vehicle has been cold started and driven for a few miles on city streets, the next step is to take it on a short freeway trip.
- Enter the freeway on-ramp and allow enough room with respect to other vehicles so that you can do a 1/2 to 3/4 throttle acceleration up to freeway speed.
- When you have accelerated up to around 60 mph maintain a steady speed of 55 to 60 mph for a at least five miles.
- Find a nice, long off ramp to exit from the freeway. As you exit, take your foot off of the accelerator and let the vehicle coast until it stops.
Step 4: More City Driving
- Repeat of the second part of Step Two.
Step 5: Have your Readiness Monitors Checked and Verified
- Drive your vehicle to your regular shop and have them check your readiness monitors, present codes, and pending codes.
- Another option is to check out this article on how to check if your monitors are in the readiness state