Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Continuous Memory Self-Test: Description
Continuous memory self-test is a functional test of PCM performed under any condition (engine running or engine off) with ignition switch turned to ON position. Unlike KOEO and KOER self-tests which can only be activated on demand, continuous monitor is always active in monitoring the system. When a fault is detected, DTC will be stored in memory. This makes it possible to diagnose intermittent faults.
There are 2 types of Continuous Memory DTCs. Emission related DTCs will illuminate the Malfunction Indicator Light (MIL) on instrument cluster. Non-emission DTCs will never illuminate MIL. On emission-related MIL codes, PCM will store DTC in continuous memory at first detection of problem. The MIL will not be illuminated, but DTC is considered by PCM to be a pending DTC. If same problem is detected in next drive cycle, MIL will illuminate. MIL will go out if fault is not present after 3 consecutive drive cycles, or PCM has been reset. An emission-related pending DTC or non-emission DTC will be erased after 40-80 warm-up cycles or PCM reset.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
Rather have a pro handle this?
A certified mobile mechanic comes to your home or office. They bring the tools, you stay comfortable. No tow truck, no waiting room, no surprises.
No obligation. See pricing before you book.