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Notes On Trouble Codes

  1. When Trouble Code P1500 occurs, MIL on instrument panel will not come on.
  2. When certain malfunctions or trouble codes initially occur, they will be temporarily stored in ECM memory, but MIL on instrument panel will not come on.
  3. The second time malfunction or trouble code is detected, MIL on instrument panel will then come on, provided ignition is turned off and then back on after malfunction or trouble code was first detected. This is referred to as the Two Trip Detection Logic and only applies to specified trouble codes. See TROUBLE CODE IDENTIFICATION  table.
NOTE: When road testing vehicle in Check Mode, the Two Trip Detection Logic will not function. In Check Mode, the MIL on instrument panel will come on the first time malfunction or trouble code is detected.
TROUBLE CODE DETECTING CONDITIONS

Trouble Code Problem Area
P0100 Open Or Short Circuit In Airflow Meter Circuit At Less Than 4000 RPM
P0101 Closed Throttle Switch On With Engine Less Than 900 RPM & Airflow Meter Output Voltage Greater Than 2.2 Volts
P0110 Open Or Short Circuit In Intake Air Temp. Sensor Circuit
P0115 Open Or Short Circuit In Engine Coolant Temp. Sensor Circuit
P0116 After Engine Operates At Least 20 Minutes, Engine Coolant Temperature Is Less Than Approx. 86°F (30°C)
P0120 Closed Throttle Switch Off & VTA Voltage Is Less Than .1 Volt Or VTA Voltage Is Greater Than 4.9 Volts
P0121 Closed Throttle Switch Is On & VTA Voltage Is Greater Than 2.0 Volts
P0125 Heated Oxygen Sensor Not Indicating Rich With Engine Speed Greater Than 1500 RPM & Vehicle Speed Is Greater Than 25 MPH For At Least 2 Minutes
P0130 Heated Oxygen Sensor Voltage Remains At .4-.55 Volt During Idling With Engine Warm
P0133 Heated Oxygen Sensor Voltage Response Time Exceeds One Second During Idling With Engine Warm
P0135 Oxygen Sensor Heater Current Is Less Than .25 Amp Or Exceeds 2 Amps Or Voltage Drop For The Heater Exceeds 5 Volts
P0136 Heated Oxygen Sensor Voltage Remains At .4 Volt Or Exceeds 5 Volt When Vehicle Is Driven At 31 MPH With Engine Warm
P0141 Oxygen Sensor Heater Current Is Less Than .25 Amp Or Exceeds 2 Amps Or Voltage Drop For The Heater Exceeds 5 Volts
P0171 With Engine Warm, Air/Fuel Ratio Is Rich
P0172 With Engine Warm, Air/Fuel Ratio Is Lean
P0201 Cylinder No. 1 Misfires Continuously
P0202 Cylinder No. 2 Misfires Continuously
P0203 Cylinder No. 3 Misfires Continuously
P0204 Cylinder No. 4 Misfires Continuously
P0300 Misfiring Of Multiple Cylinders During Same 200-1000 Engine Revolutions
P0301 No. 1 Cylinder Misfiring Detected For Each 200 Or 1000 Engine Revolutions
P0302 No. 2 Cylinder Misfiring Detected For Each 200 Or 1000 Engine Revolutions
P0303 No. 3 Cylinder Misfiring Detected For Each 200 Or 1000 Engine Revolutions
P0304 No. 4 Cylinder Misfiring Detected For Each 200 Or 1000 Engine Revolutions
P0335 No Crankshaft Position Sensor Signal To ECM
P0336 Deviation In Crankshaft & Camshaft Position Sensor Signals
P0340 No Camshaft Position Sensor Signal To ECM
P0401 With Engine Warm & Driven At 50 MPH For 5 Minutes, EGR Gas Temp. Sensor Value Does Not Exceed Ambient Air Temperature By 72°F (40°C)
P0402 EGR Valve Always Open Or EGR Gas Temp. Sensor Value Is High During EGR Cut Off With Engine Cold
P0420 With Engine Warm, Heated Oxygen Sensors Have Same Wave Patterns
P0441 Evaporative Emission System Has Improper Response To Computer Command
P0500 No Vehicle Speed Sensor Signal To ECM
P0505 Idle Speed Varies Greatly From ECM Target Speed
P0510 Throttle Position Switch Does Not Turn On When Vehicle Is Driven
P1300 (1) No IGF Signal To ECM Per Consecutive IGT Signals
P1500 (1) No Starter Signal To ECM
P1510 (1) Intake Air Volume Too Low With Supercharger Magnetic Clutch On With Engine Speed Of At Least 2800 RPM
P1600 (1) Open Circuit In ECM Back-Up Power Source
P1605 (1) ECM Malfunction For Knock Control
P1705 (1) Direct Clutch Speed Sensor Output Is 300 RPM Or Less With Vehicle At 20 MPH Or More & With Park/Neutral Position Switch Off
P1765 (1) With Engine Warm, Current Flow To Shift Solenoid Valve SLN Is .2 Amp Or Less For One Second With Engine At 500 RPM Or More, Or With Park/Neutral Position Switch Off
P1780 (1) Park/Neutral Position Switch On When Driving Vehicle At 44 MPH Or More With Engine At 1500-2500 RPM
(1) This is a Toyota code.
TROUBLE CODE IDENTIFICATION

Code Two Trip Logic System Affected Probable Cause
P0100  No Mass Airflow Meter Circuit Malfunction Airflow Meter Or Circuit, ECM
P0101  Yes Mass Airflow Meter Circuit Range/Performance Airflow Meter
P0110  No Intake Air Temperature Circuit Malfunction Intake Air Temp. Sensor Or Circuit, ECM
P0115  No Engine Coolant Temperature Circuit Malfunction Engine Coolant Temp. Sensor Or Circuit, ECM
P0116  Yes Engine Coolant Temperature Circuit Range/Performance Engine Coolant Temp. Sensor, Cooling System
P0120  No Throttle Position Circuit Malfunction Throttle Position Sensor Or Circuit, ECM
P0121  Yes Throttle Position Circuit Range/Performance Throttle Position Sensor
P0125  No Insufficient Coolant Temperature For Closed Loop Fuel Control Heated Oxygen Sensor Or Circuit
P0130  Yes Heated Oxygen Sensor Circuit Malfunction (Bank 1, Sensor 1) Heated Oxygen Sensor, Fuel Trim Malfunction
P0133  Yes Heated Oxygen Sensor Circuit Slow Response (Bank 1, Sensor 1) Heated Oxygen Sensor
P0135  Yes Heated Oxygen Sensor Circuit Malfunction (Bank 1, Sensor 1) Heated Oxygen Sensor Or Circuit, ECM
P0136  Yes Heated Oxygen Sensor Circuit Malfunction (Bank 1, Sensor 2) Heated Oxygen Sensor
P0141  Yes Heated Oxygen Sensor Circuit Malfunction (Bank 1, Sensor 2) Heated Oxygen Sensor Or Circuit, ECM
P0171  Yes System Too Lean (Fuel Trim) Air Intake Hose, Fuel Pressure, Injector, Oxygen Sensor Or Circuit, Airflow Meter, Engine Coolant Temp. Sensor
P0172  Yes System Too Rich (Fuel Trim) Fuel Pressure, Injector, Oxygen Sensor Or Circuit, Airflow Meter, Engine Coolant Temp. Sensor
P0201  Yes Injector Circuit Malfunction (Cyl. No. 1) Injector Or Circuit, Ignition System, Improper Valve Clearance, Compression Pressure
P0202  Yes Injector Circuit Malfunction (Cyl. No. 2) Injector Or Circuit, Ignition System, Improper Valve Clearance, Compression Pressure
P0203  Yes Injector Circuit Malfunction (Cyl. No. 3) Injector Or Circuit, Ignition System, Improper Valve Clearance, Compression Pressure
P0204  Yes Injector Circuit Malfunction (Cyl. No. 4) Injector Or Circuit, Ignition System, Improper Valve Clearance, Compression Pressure
P0300  No Random Misfire Detected Injector, Fuel Pressure, EGR, Ignition System, Improper Valve Clearance, Improper Valve Timing, Airflow Meter, Compression Pressure, Engine Coolant Temp. Sensor
P0301  Yes Misfire Detected (Cylinder No. 1) Injector, Fuel Pressure, EGR, Ignition System, Improper Valve Clearance, Improper Valve Timing, Airflow Meter, Compression Pressure, Engine Coolant Temp. Sensor
P0302  Yes Misfire Detected (Cylinder No. 2) Injector, Fuel Pressure, EGR, Ignition System, Improper Valve Clearance, Improper Valve Timing, Airflow Meter, Compression Pressure, Engine Coolant Temp. Sensor
P0303  Yes Misfire Detected (Cylinder No. 3) Injector, Fuel Pressure, EGR, Ignition System, Improper Valve Clearance, Improper Valve Timing, Airflow Meter, Compression Pressure, Engine Coolant Temp. Sensor
P0304  Yes Misfire Detected (Cylinder No. 4) Injector, Fuel Pressure, EGR, Ignition System, Improper Valve Clearance, Improper Valve Timing, Airflow Meter, Compression Pressure, Engine Coolant Temp. Sensor
P0325  No Knock Sensor No. 1 Circuit Malfunction Knock Sensor No. 1 Or Circuit, ECM
P0335  Yes Crankshaft Position Sensor Circuit Crankshaft Position Sensor Or Circuit, Starter, ECM
P0336  Yes Crankshaft Position Sensor Circuit Range/Performance Mechanical Malfunction, ECM
P0340  Yes Camshaft Position Sensor Circuit Malfunction Camshaft Position Sensor Or Circuit, Starter, ECM
P0401  Yes Exhaust Gas Recirculation Flow Insufficient Detected EGR Valve Or Hoses, EGR VSV Or Circuit, EGR Gas Temp. Sensor Circuit, ECM
P0402  Yes Exhaust Gas Recirculation Flow Excessive Detected EGR Valve Or Hoses, EGR VSV Or Circuit, EGR Gas Temp. Sensor Circuit, ECM
P0420  No Catalyst System Efficiency Below Threshold Catalytic Converter, Oxygen Sensor Or Circuit
P0441  Yes Evaporative Emission Control System EVAP VSV Or Circuit, Defective Hoses Or Charcoal
P0441  Yes Incorrect Purge Flow Canister, ECM
P0500  No Vehicle Speed Sensor Malfunction Vehicle Speed Sensor Or Circuit, Instrument Cluster, ECM
P0505  Yes Idle Control System Malfunction IAC Valve Or Circuit, A/C Idle-Up VSV
P0510  Yes Closed Throttle Switch Malfunction TPS Or Circuit, ECM
P1300 (1) No Ignitor Circuit Malfunction Ignitor Circuit To ECM, Ignitor, ECM
P1500 (1) No Starter Signal Circuit Malfunction Starter Signal Circuit, Ignition Switch, Starter Relay, ECM
P1600 (1) No ECM BATT Malfunction ECM Power Source
(1) This is a Toyota code.
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