FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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3) Concern Setting Continious Memory Code Isn't Present

The EEC processor will erase a Continuous Memory code if the concern that caused it has not been present for 40 or 80 warm-up cycles, depending on the vehicle. A warm-up cycle occurs when the vehicle is started with the coolant temperature below 120° Fahrenheit and then shutdown with the coolant temperature above 150°. If a vehicle is brought in for service with a MIL complaint and the vehicle is driven or otherwise allowed to warm-up before Self-Test is run, the code may be cleared before the technician tests it.