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DTC P0140 [MZR-CD (RF Turbo)]

id0102f1805300

DTC P0140 | A/F sensor no activity
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DETECTION CONDITION | • The PCM monitors the input signal from A/F sensor while the engine running. The A/F sensor signal does not change to rich from lean or to lean from rich for 100 s after the engine started. The PCM determines that the A/F sensor is not activity.
POSSIBLE CAUSE | • A/F sensor deterioration • A/F sensor heater malfunction • Leakage exhaust system • Open circuit or short to ground in wiring harness between A/F sensor terminal A and PCM terminal 93 • Open circuit or short to ground in wiring harness between A/F sensor terminal B and PCM terminal 85 • Insufficient compression • Engine malfunction

Diagnostic procedure

STEP | INSPECTION | ACTION
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1 | VERIFY FREEZE FRAME DATA HAS BEEN RECORDED • Has FREEZE FRAME DATA been recorded? | Yes | Go to the next step.
No | Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2 | VERIFY RELATED REPAIR INFORMATION AVAILABILITY • Verify related service repair information availability. • Is any related repair information available? | Yes | Perform repair or diagnosis according to the available repair information. • If the vehicle is not repaired, go to the next step.
No | Go to the next step.
3 | IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA • Is DTC P0140 on FREEZE FRAME DATA? | Yes | Go to the next step.
No | Go to troubleshooting procedures for DTC on FREEZE FRAME DATA. (See DTC TABLE [MZR-CD (RF Turbo)].)
4 | VERIFY CURRENT INPUT SIGNAL STATUS • Warm up engine. • Access O2S11 PID using the WDS or equivalent. • Verify PID while racing engine in NEUTRAL. • Is PID normal? - Less than 1 mA when suddenly depressing accelerator pedal (rich condition) - More than 1 mA just after releasing the accelerator pedal (lean condition) | Yes | Go to step 9.
No | Go to the next step.
5 | INSPECT INSTALLATION OF A/F SENSOR • Inspect if the A/F sensor is loosely installed. • Is the sensor installed securely? | Yes | Go to the next step.
No | Install the sensor securely, then go to Step 11.
6 | INSPECT GAS LEAKAGE FROM EXHAUST SYSTEM • Visually inspect if there is any gas leakage between the exhaust manifold and A/F sensor. • Is there gas leakage? | Yes | Repair or replace any malfunctioning exhaust part, then go to Step 11.
No | Go to the next step.
7 | INSPECT A/F SENSOR CIRCUIT FOR OPEN CIRCUIT • Inspect for continuity between the following terminals: - A/F sensor terminal A (wiring harness-side) and PCM terminal 93 (wiring harness-side) - A/F sensor terminal B (wiring harness-side) and PCM terminal 85 (wiring harness-side) • Are there continuity? | Yes | Go to the next step.
No | Repair or replace the wiring harness for open circuit, then go to Step 11.
8 | INSPECT A/F SENSOR CIRCUIT FOR SHORT TO GROUND • Inspect for continuity between the following terminals: - A/F sensor terminal A (wiring harness-side) and body ground - A/F sensor terminal B (wiring harness-side) and body ground • Are there continuity? | Yes | Repair or replace the wiring harness for short to ground, then go to Step 11.
No | Go to the next step.
9 | INSPECT SEALING OF ENGINE COOLANT PASSAGE • Perform the ENGINE COOLANT LEAKAGE INSPECTION. (See ENGINE COOLANT LEAKAGE INSPECTION [MZR-CD (RF Turbo)].) • Is there any malfunction? | Yes | Repair or replace the malfunctioning part according to inspection results, then go to Step 11.
No | Go to the next step.
10 | INSPECT ENGINE COMPRESSION • Inspect the engine compression. (See COMPRESSION INSPECTION [MZR-CD (RF Turbo)].) • Is it normal? | Yes | Go to the next step.
No | Perform engine overhaul for repairs, then go to the next step.
11 | VERIFY TROUBLESHOOTING OF DTC P0140 COMPLETED • Make sure to reconnect all disconnected connectors. • Turn the engine switch to the ON position (Engine off). • Clear the DTC from memory using the WDS or equivalent. • Start the engine. • Perform the Repair Verification Drive Mode. (See OBD DRIVE MODE [MZR-CD (RF Turbo)].) • Is the PENDING CODE for this DTC present? | Yes | Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION [MZR-CD (RF Turbo)].)
No | Go to the next step.
12 | VERIFY AFTER REPAIR PROCEDURE • Perform the "After Repair Procedure". (See AFTER REPAIR PROCEDURE [MZR-CD (RF Turbo)].) • Are any DTC present? | Yes | Go to the applicable DTC troubleshooting. (See DTC TABLE [MZR-CD (RF Turbo)].)
No | Troubleshooting completed.