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.
Output Test Mode
Output test mode allows the technician to activate most PCM output devices. Cooling fans can be activated independently of all other outputs. To access OUTPUT TEST MODE, turn ignition switch to OFF position. Ensure scan tool is properly connected. Program scan tool using the following steps:
- Turn ignition on.
- Select vehicle and engine selection menu (optional).
- Select year, engine, model and any additional information requested by scan tool.
- Select DIAGNOSTIC DATA LINK.
- Select PCM.
- Select ACTIVE COMMAND MODES.
- Follow operating instructions from scan tester.
- Command device(s) on or off (i.e., All ON, HIGH FAN, etc.).
- Select START to activate output.
- Select STOP to turn outputs off.
NO RELATED
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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.