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DTC P2128 00: App Sensor No. 2 Circuit High Input: Notes

DTC P2128 00 DETECTION CONDITIONS AND POSSIBLE CAUSES (SKYACTIV-G 2.0, SKYACTIV-G 2.5)

DTC P2128:00	APP sensor No. 2 circuit high input
DETECTION CONDITION	The PCM monitors the input voltage from APP sensor No. 2. If the input voltage at the PCM terminal 2AS is more than 4.9 V , the PCM determines that the APP sensor No. 2 circuit has a malfunction. Diagnostic support note This is a continuous monitor (CCM). The check engine light illuminates if the PCM detects the above malfunction condition during the first drive cycle. FREEZE FRAME DATA (Mode 2)/Snapshot data is available. DTC is stored in the PCM memory.
FAIL-SAFE FUNCTION	Regulates the upper limit of the APP sensor output.
POSSIBLE CAUSE	APP sensor connector or terminals malfunction PCM connector or terminals malfunction APP sensor No. 2 malfunction Short to power supply in wiring harness between APP sensor terminal E and PCM terminal 2AS Open circuit in wiring harness between APP sensor terminal D and PCM terminal 2AT PCM malfunction
Courtesy of MAZDA MOTORS CORP.

CAUTION:

Verify the malfunction symptom according to not only the PID value but also the symptom troubleshooting.

RELATED PIDS

Item (definition)	Unit/Condition	Definition	Condition/Specification (Reference)
APP1	%	Accelerator pedal opening angle (absolute value) input from APP sensor No. 1	Accelerator pedal released: Approx. 15% Accelerator pedal fully depressed: Approx. 82%
APP1	V	APP sensor No. 1 voltage	Accelerator pedal released: Approx. 0.75 V Accelerator pedal fully depressed: Approx. 4.1 V
APP2	%	Accelerator pedal opening angle (absolute value) input from APP sensor No. 2	Accelerator pedal released: Approx. 7.45% Accelerator pedal fully depressed: Approx. 41%
APP2	V	APP sensor No. 2 voltage	Accelerator pedal released: Approx. 0.38 V Accelerator pedal fully depressed: Approx. 2.05 V