SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSMAZDA20105 SPORT, 2.3 L, STANDARDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 550 (ON-BOARD DIAGNOSTIC [ENGINE CONTROL SYSTEM L3))DTC P2128 [L3]NOTES
2010 Mazda 5 Sport, 2.3 L, Standard

DTC P2128 [L3]: Notes

2010 Mazda 5 Sport, 2.3 L, StandardSECTION Notes
WARNING: This page is about a different car, the 2008 Mazda 5. However, it is still accessible from the selected car via links, so may be relevant.
DTC P2128 [L3] DETECTION CONDITIONS AND POSSIBLE CAUSES

DTC P2128 Accelerator pedal position (APP) sensor No.2 circuit high input
DETECTION CONDITION 
  • The PCM monitors the input voltage from APP sensor No.2 when the engine is running. If the input voltage is above 7.2 V for 1s, the PCM determines that the APP sensor No.2 circuit has malfunction.

Diagnostic support note 
  • This is a continuous monitor (CCM).
  • MIL illuminates if the PCM detects the above malfunction condition during the first drive cycle.
  • FREEZE FRAME DATA is available.
  • The DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • APP sensor No.2 malfunction
  • Connector or terminal malfunction
  • Open circuit in wiring harness between APP sensor terminal F and main relay
  • Open circuit in wiring harness between APP sensor terminal D and body ground
  • Open circuit in wiring harness between APP sensor terminal E and PCM terminal 1AO
  • Short to power supply in wiring harness between APP sensor terminal E and PCM terminal 1AO
  • PCM malfunction
G05542989
RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Affiliate disclosure: We may earn a commission at no extra cost to you.

Shop Manual-Ready ToolsFree Quote CheckQuote Shield Pro

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.