DTC P2123 [L8, LF]
id0102b1811800
DTC P2123 |
APP sensor No.1 circuit high input |
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DETECTION CONDITION
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• The PCM monitors the input voltage from APP sensor No.1 when the engine is running. If the input voltage is above 4.8 V, the PCM determines that the APP sensor No.1 circuit input voltage is high.
Diagnostic support note
• This is a continuous monitor (CCM).
• The MIL illuminates if the PCM detects the above malfunction condition during the first drive cycle.
• FREEZE FRAME DATA (Mode 2/Mode 12) is available.
• The DTCs is stored in the PCM memory.
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POSSIBLE CAUSE
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• APP sensor connector or terminals malfunction
• PCM connector or terminals malfunction
• Short to power supply in wiring harness between APP sensor terminal F and PCM terminal 1AO
• APP sensor No.1 power supply circuit and signal circuit are shorted to each other
• Open circuit in wiring harness between APP sensor terminal E and PCM terminal 1AS
• APP sensor No.1 malfunction
• PCM malfunction
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Diagnostic procedure
STEP |
INSPECTION |
ACTION |
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1
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VERIFY FREEZE FRAME DATA (MODE 12) HAS BEEN RECORDED
• Has the FREEZE FRAME DATA (Mode 12) been recorded?
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Yes
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Go to the next step.
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No
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Record the FREEZE FRAME DATA (Mode 12) on the repair order, then go to the next step.
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2
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VERIFY RELATED SERVICE INFORMATION AVAILABILITY
• Verify related Service Information availability.
• Is any related Service Information available?
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Yes
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Perform repair or diagnosis according to the available Service Information.
• If the vehicle is not repaired, go to the next step.
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No
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Go to the next step.
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3
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INSPECT APP SENSOR CONNECTOR AND TERMINALS
• Turn the ignition switch off.
• Disconnect the APP sensor connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Is there any malfunction?
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Yes
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Repair or replace the connector or terminals, then go to Step 9.
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No
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Go to the next step.
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4
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INSPECT PCM CONNECTOR AND TERMINALS
• Disconnect the PCM connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Is there any malfunction?
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Yes
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Repair or replace the connector or terminals, then go to Step 9.
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No
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Go to the next step.
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5
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INSPECT APP SENSOR NO.1 SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY
• APP sensor and PCM connectors are disconnected.
• Turn the ignition switch to the ON position (engine off).
• Measure the voltage between APP sensor terminal F (wiring harness-side) and body ground.
• Is there any voltage?
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Yes
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Repair or replace the wiring harness for a possible short to power supply, then go to Step 9.
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No
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Go to the next step.
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6
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INSPECT APP SENSOR NO.1 POWER SUPPLY AND SIGNAL CIRCUIT FOR SHORT TO EACH OTHER
• APP sensor and PCM connectors are disconnected.
• Turn the ignition switch off.
• Inspect for continuity between APP sensor terminal D and F (wiring harness-side).
• Is there continuity?
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Yes
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Repair or replace the suspected wiring harness, then go to Step 9.
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No
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Go to the next step.
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7
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INSPECT APP SENSOR NO.1 GROUND CIRCUIT FOR OPEN CIRCUIT
• APP sensor and PCM connectors are disconnected.
• Inspect for continuity between APP sensor terminal E (wiring harness-side) and PCM terminal 1AS (wiring harness-side).
• Is there continuity?
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Yes
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Go to the next step.
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No
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Repair or replace the wiring harness for a possible open circuit, then go to Step 9.
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8
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INSPECT APP SENSOR NO.1
• Reconnect the APP sensor and PCM connectors.
• Inspect APP sensor No.1.
• Is there any malfunction?
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Yes
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Replace the APP sensor, then go to the next step.
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No
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Go to the next step.
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9
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VERIFY DTC TROUBLESHOOTING COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the PCM memory using the M-MDS.
• Start the engine and warm it up completely.
• Perform the KOEO/KOER self test.
(See KOEO/KOER SELF TEST [L8, LF].)
• Is the same DTC present?
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Yes
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Replace the PCM, then go to the next step.
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No
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Go to the next step.
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10
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VERIFY AFTER REPAIR PROCEDURE
• Perform the “AFTER REPAIR PROCEDURE”.
• Are any DTCs present?
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Yes
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Go to the applicable DTC troubleshooting.
(See DTC TABLE [L8, LF].)
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No
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DTC troubleshooting completed.
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