Diagnostic Aids
After confirming DTC P1120, use scan tool to access CURRENT DATA to confirm APP sensor voltage with throttle open and closed. If voltage displayed on scan tool for ACCEL POS and ACCEL POS #2 is always zero volts, VC circuit may be open. If voltage displayed on scan tool for ACCEL POS is always zero volts and voltage display for ACCEL POS #2 is 1.8-2.7 volts with fully closed throttle and 4.7-5.1 volts with fully open throttle, VPA circuit may be open or shorted. If voltage displayed on scan tool for ACCEL POS #2 is always zero volts and voltage display for ACCEL POS is .3-.9 volt with fully closed throttle and 3.2-4.8 volts with fully open throttle, VPA2 circuit may be open or shorted. If voltage displayed on scan tool for ACCEL POS and ACCEL POS #2 is always 5 volts, E2 circuit may be open. Using scan tool, read freeze frame data. Freeze frame records engine conditions when malfunction is detected.