Diagnostic Aids

With throttle closed, TPS voltage should be less than 1.25 volt. TPS voltage should steadily increase as throttle is opened. Code 21A appears if Purple/Red or Purple/Orange wire is open or shorted to voltage. If code is intermittent, see TESTS W/O CODES article.

Fig 1: Code 21B Circuit Diagram

Fig 2: Code 21B Flow Chart