Diagnostic Aids

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Depending on the Start Up ECT, the Desired Throttle Position percentage maybe greater or less than the Throttle Position with the TAC motor at rest. When the ignition is initially turned ON, or when the engine is cranking or running the Desired and Actual Throttle positions should closely match.
Inspect for a condition in which the throttle valve may have been held open. For example, ice may have formed in the throttle bore causing the throttle valve not to close.
A high resistance condition on the throttle position and throttle actuator control circuits could cause a DTC to set.
A low battery condition may cause a DTC to set.