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.
1990 Ford Probe GL, AutomaticFACTORY OEM SERVICE PROCEDURE
Key On Engine Off (KOEO) Self-Test: Notes
NOTE:
The following items should be noted before beginning KOEO test procedure:
- DO NOT depress throttle during KOEO SELF-TEST.
- When the ignition key is turned to the ON position, a 3-second series of signals will be displayed.
- It may be necessary to repair non-electronic faults before running the QUICK TEST procedures.
- If no codes are displayed or a 00 is displayed on the Scan tool, proceed to the KOER SELF-TEST.
- If no codes are displayed and vehicle is a no start, or if a code is displayed but CHECK ENGINE light does not light prior to activating Self-Test, proceed to TEST D3.
Factory Service Tools
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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.
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