Infiniti All models error codes
Codes
- P0171Error codeSystem too lean, Bank 1. Vacuum leak, dirty MAF sensor, low fuel pressure, or failing upstream O2 sensor. On the VQ35DE in the FX35 and G35, intake manifold gasket leaks are a documented cause at higher mileage. Smoke test for vacuum leaks before replacing sensors
- P0172Error codeSystem too rich, Bank 1. Failed upstream O2 sensor, stuck-open injector, or ECT sensor fault. When accompanied by P0128, thermostat replacement typically resolves both codes
- P0174Error codeSystem too lean, Bank 2. Mirror of P0171 on the opposite bank. When P0171 and P0174 appear together on a V6, suspect a shared cause - dirty MAF sensor or a vacuum leak at the intake plenum rather than a bank-specific problem
- P0175Error codeSystem too rich, Bank 2. When appears with P0172, shared cause is more likely than bank-specific fault. Check MAF and thermostat first
- P0180Error codeTank Fuel Temp Sensor
- P0222Error codeThrottle position sensor B circuit low. One of two TPS signals in the electronic throttle body is reading low. On the Q50 and QX60 with drive-by-wire, this often points to a failing throttle body assembly. Cleaning the throttle body sometimes resolves it temporarily
- P0325Error codeKnock Sensor, Bank 1
- P0327Error codeKnock sensor circuit low, Bank 1. On the VQ35DE, the knock sensor wiring harness runs along the underside of the intake manifold and is prone to abrasion damage.
- P0330Error codeKnock Sensor, Bank 2
- P0335Error codeCrankshaft position sensor circuit fault. No signal from the CKP sensor. Symptoms include no-start or stalling. On the VQ series, the CKP sensor is a known failure item at higher mileage. Replace sensor; inspect wiring harness for damage near the flywheel
- P0340Error codeCamshaft position sensor circuit fault, Bank 1. Failed sensor or timing chain wear affecting signal consistency. On higher-mileage VQ35DE and VQ37VHR engines, timing chain stretch can cause P0340 alongside P0300. Diagnose chain condition before replacing sensors
- P0351Error codeP0356 - Ignition coil primary circuit fault, cylinders 1-6. Failed coil primary winding. On the VQ series, coil failure is a routine higher-mileage repair. Symptoms are a cylinder-specific misfire alongside the coil code. Swap the coil to confirm before replacing
- P0400Error codeEGR flow insufficient. The EGR system is not flowing the expected amount of exhaust gas during the test cycle. On Infiniti diesel variants sold outside North America, carbon buildup on the EGR valve is the primary cause
- P0402Error codeEGRC/BPT Valve
- P0403Error codeEGR Volume Control Valve Circuit
- P0412Error codeSecondary air injection system switching valve circuit fault. The air pump system has a fault - common on cold-climate models where the secondary air injection pump seizes from moisture. Pump replacement is the standard repair
- P0420Error codeCatalyst efficiency below threshold, Bank 1. Failed upstream O2 sensor at lower mileage; catalytic converter at end of life past 150,000 miles. On the G35 and FX35, confirm O2 sensor function before condemning the converter
- P0440Error codeEVAP Small Leak
- P0441Error codeEVAP system incorrect purge flow. Failed purge solenoid, cracked vacuum hose, or faulty fuel cap. Check the fuel cap seal first
- P0446Error codeEVAP vent control circuit. The EVAP canister vent valve is not opening or closing correctly. Causes include a stuck valve, wiring fault, or failed canister. On the QX60, this code sometimes accompanies P0448 when both the vent valve and canister need replacement
- P0448Error codeEVAP vent control circuit open. The EVAP canister vent solenoid has a fault. On the Q50, a faulty charcoal canister causing this code has been documented - P0448 can return even after vent valve replacement if the canister itself is defective
- P0450Error codeEVAP Pressure Sensor
- P0455Error codeEVAP system large leak. Loose or damaged fuel cap, cracked EVAP hose, or failed vent valve. Start with the fuel cap; smoke test if not the cause
- P0491Error codeSecondary air injection insufficient, Bank 1. The secondary air pump is operating but not injecting adequate airflow. Causes include a clogged air injection port, a stuck combination valve, or a partially failed pump. Often appears alongside P0412
- P0500Error codeVehicle Speed Sensor
- P0505Error codeIACV/AAC Valve
- P0506Error codeIdle RPM too low. Dirty throttle body, vacuum leak, or failed IACV. On the VQ35DE, the throttle body accumulates carbon deposits that restrict airflow at idle - cleaning resolves it in most cases
- P0507Error codeIdle RPM too high. Vacuum leak, dirty throttle body, or failed IACV on older models. On the VQ35DE, a dirty throttle body is the primary cause. Clean with throttle body cleaner
- P0510Error codeClosed TP Sensor
- P0562Error codeSystem voltage low. Failing battery, corroded terminals, or charging system fault. On the QX80 and QX56 with dual battery systems, one battery can fail while the other masks the fault until a cold morning or sustained electrical load reveals it
- P0600Error codeSerial communication link fault. The ECM is not communicating with one or more control modules on the internal data link. Causes include a failed ECM, a wiring fault, or a module that has lost its calibration. Often appears after a voltage spike or battery failure
- P0638Error codeThrottle actuator control range/performance. The electronic throttle body actuator is not responding within expected parameters. On the Q50 and QX60, this code can trigger a reduced throttle response mode. Clean throttle body first; replace if fault returns
- P0700Error codeTransmission control system malfunction. General code - TCM has stored its own specific faults. Always appears alongside additional transmission codes. Read all stored codes; P0700 alone does not describe the fault
- P0710Error codeATF Temp Sensor
- P0720Error codeOutput shaft speed sensor circuit fault. Erratic speedometer and poor shift scheduling. On the 7-speed JR710E transmission in the Q50 and QX60, this sensor is a known wear item. Replace sensor
- P0740Error codeTorque converter clutch circuit fault. Failed TCC solenoid, contaminated fluid, or worn clutch plate. Highway shudder between 40-60 mph often precedes this code. Change fluid first; replace TCC solenoid if shudder persists
- P0744Error codeTorque converter clutch circuit intermittent. Intermittent TCC solenoid fault - fluid condition is usually the trigger. Fresh transmission fluid often clears this code without further repair on lower-mileage vehicles
- P0745Error codeLine Pressure S/V
- P0750Error codeShift solenoid A circuit fault. Failed solenoid or contamination in valve body. Solenoid pack replacement is the standard repair on the RE7R01A and 7AT transmissions used in newer Infiniti models
- P1031Error codeHeated oxygen sensor (H02S), bank 1, heater - voltage low
- P1032Error codeHeated oxygen sensor (H02S), bank 1, heater - voltage high
- P1051Error codeHeated oxygen sensor (H02S), bank 2, heater - voltage low
- P1052Error codeHeated oxygen sensor (H02S), bank 2, heater - voltage high
- P1065Error codeEngine control module (ECM) - battery voltage supply
- P1078Error codeCamshaft position (CMP) sensor, exhaust - low voltage
- P1084Error codeCamshaft position (CMP) sensor, exhaust - high voltage
- P1087Error codeVVEL Small Event Angle Malfunction Bank 1
- P1088Error codeVVEL Small Event Angle Malfunction Bank 2
- P1089Error codeVVEL Control Shaft Position Sensor Bank 1 Circuit
- P1090Error codeVVEL Actuator Motor Bank 1