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Home >> Suzuki >> 2007 >> Grand Vitara Base, AWD, Automatic >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine General Information And Diagnosis >> Diagnostic Information And Procedures >> DTC P2127/P2128: Pedal Position Sensor (Sub) Circuit Low/High >> DTC Troubleshooting
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DTC Troubleshooting

NOTE: Before this trouble shooting is performed, read the precautions for DTC troubleshooting by referring to PRECAUTIONS FOR DTC TROUBLESHOOTING .
TROUBLESHOOTING TABLE

Step Action YES NO
1  Was "Engine and Emission Control System Check" performed?  Go to Step 2. Go to ENGINE AND EMISSION CONTROL SYSTEM CHECK .
2  APP sensor assembly mounting check 
  1. Check that APP sensor assembly has been mounted to vehicle body properly (no pinched floor carpet, etc).

Is it in good condition? 		 Go to Step 3. Reinstall APP sensor assembly properly by referring to ACCELERATOR PEDAL POSITION (APP) SENSOR ASSEMBLY REMOVAL AND INSTALLATION .
3  APP sensor (sub) and its circuit check 
  1. Connect scan tool to DLC with ignition switch turned OFF.
  2. Turn ON ignition switch, check "APP Sensor 2 Volt" displayed on scan tool when accelerator pedal is idle position and fully depressed.

Is displayed APP sensor value as described voltage in Scan Tool Data? 		 Intermittent trouble. Check for intermittent by referring to intermittent and poor connection. Go to Step 4.
4  Wire harness check 
  1. Turn ignition switch OFF position.
  2. Disconnect connectors from APP sensor and ECM.
  3. Check for proper terminal connection to APP sensor and ECM connectors.
  4. If connections are OK, check that APP sensor (sub) circuit is as follows.
    • Wiring harness resistance of each APP sensor (sub) power supply, signal and ground circuit is less than 3 Ω
    • Insulation resistance of each APP sensor (sub) power supply and signal circuit is infinity between AAP sensor connector and vehicle body ground.
    • Insulation resistance of wire harness is infinity between APP sensor (sub) power supply terminal and each other terminal at APP sensor connector.
    • Circuit voltage of each APP sensor (sub) power supply, signal and ground circuit is 0 - 1 V with ignition switch turned ON

Are they in good condition? 		 Go to Step 5. Repair or replace APP sensor (sub) power supply, signal and/or ground circuit (s).
5  APP sensor power supply voltage check 
  1. Connect connectors to ECM.
  2. Turn ignition switch ON position.
  3. Check that circuit voltage is 5 V between APP sensor (sub) power supply terminal and vehicle body ground.

Is it in good condition? 		 Go to Step 6. Substitute a known good ECM and recheck.
6  APP sensor check 
  1. Check APP sensor for performance by referring to ACCELERATOR PEDAL POSITION (APP) SENSOR ASSEMBLY ON-VEHICLE INSPECTION .

Is it in good condition? 		 Substitute a known good ECM and recheck. Replace APP sensor assembly.
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