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.
Code 538 Displayed: System Failed To Recognize WOT Test
Repeat KOER SELF-TEST as follows:
- Activate SELF-TEST.
- Start engine.
- Observe ID Code start of test.
- Observe Dynamic Response Code 1 (Code 0 with STAR tester).
- Perform brief WOT.
- Testing is complete; Diagnostic Test Code (DTC) output begins.
Ensure vehicle speed reached 2000 RPM during WOT. If Code 538 is present, replace PCM. Repeat QUICK TEST . If Code 538 is not present, vehicle has passed dynamic response test. Service other codes if necessary.
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra 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.