Honda Insight 29 DTCs You Need to Understand
Discover the top 29 Diagnostic Trouble Codes (DTCs) commonly found in Honda Insight vehicles. This guide will help you understand these issues and their solutions, allowing you to effectively troubleshoot and maintain your vehicle.
HONDA INSIGHT TOP 29 DTC
DTC P0420: Catalyst System Efficiency Below Threshold
Description: The efficiency of the catalytic converter has dropped below the acceptable level.
Cause: A faulty catalytic converter, oxygen sensors, or a leak in the exhaust system.
Symptoms: Poor fuel economy, reduced performance, and a check engine light.
Location of Fault: Catalytic converter and its related oxygen sensors in the exhaust system.
How to Fix: Inspect and replace the catalytic converter if needed, or replace faulty oxygen sensors.
DTC P0A7F: Battery Module Deterioration
Description: The hybrid battery module has deteriorated, causing a decrease in overall performance.
Cause: Aging or damaged hybrid battery module.
Symptoms: Reduced battery performance, decreased fuel efficiency, and a check engine light.
Location of Fault: Hybrid battery pack.
How to Fix: Inspect the hybrid battery pack and replace the deteriorated module or the entire pack if necessary.
DTC P0171: System Too Lean (Bank 1)
Description: The air-fuel mixture in bank 1 is too lean, causing inefficient combustion.
Cause: Vacuum leaks, faulty mass air flow sensor, or malfunctioning fuel injectors.
Symptoms: Rough idling, hesitation, and a check engine light.
Location of Fault: Bank 1 of the engine, which includes the cylinders and associated components.
How to Fix: Inspect and repair any vacuum leaks, clean or replace the mass air flow sensor, and clean or replace fuel injectors.
DTC P0303: Cylinder 3 Misfire Detected
Description: The engine control module has detected a misfire in cylinder 3.
Cause: Faulty spark plug, ignition coil, fuel injector, or mechanical issue.
Symptoms: Rough running, poor performance, and a check engine light.
Location of Fault: Cylinder 3 in the engine.
How to Fix: Inspect and replace the spark plug, ignition coil, or fuel injector for cylinder 3, and check for any mechanical issues.
DTC P0456: Evaporative Emission System Leak Detected (Very Small Leak Detected)
Description: A very small leak has been detected in the evaporative emissions system.
Cause: Loose or damaged fuel cap, damaged or cracked hoses, or faulty purge or vent valves.
Symptoms: Check engine light.
Location of Fault: Evaporative emissions system, including fuel cap, hoses, and valves.
How to Fix: Tighten or replace the fuel cap, inspect and replace damaged hoses, and test and replace purge or vent valves as necessary.
DTC P0128: Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)
Description: The engine coolant temperature is lower than the thermostat’s regulating temperature.
Cause: Stuck-open thermostat, faulty engine coolant temperature sensor, or low coolant level.
Symptoms: Poor engine performance, reduced fuel efficiency, and a check engine light.
Location of Fault: Engine thermostat and coolant temperature sensor.
How to Fix: Replace the thermostat, check and replace the coolant temperature sensor, and ensure the coolant level is correct.
DTC P0AA6: Hybrid Battery Pack Voltage Sensor Circuit Range/Performance
Description: The voltage sensor circuit for the hybrid battery pack is not performing within the expected range.
Cause: Faulty voltage sensor, damaged wiring, or poor connections.
Symptoms: Reduced hybrid performance, decreased fuel efficiency, and a check engine light.
Location of Fault: Hybrid battery pack voltage sensor circuit.
How to Fix: Inspect and replace the voltage sensor, repair damaged wiring, and ensure proper connections.
DTC P0172: System Too Rich (Bank 1)
Description:The air-fuel mixture in bank 1 is too rich, causing inefficient combustion.
Cause: Faulty mass air flow sensor, malfunctioning fuel injectors, or a faulty oxygen sensor.
Symptoms: Rough idling, hesitation, poor fuel economy, and a check engine light.
Location of Fault: Bank 1 of the engine, which includes the cylinders and associated components.
How to Fix: Inspect and clean or replace the mass air flow sensor, clean or replace fuel injectors, and check or replace the oxygen sensor.
DTC P0685: ECM/PCM Power Relay Control Circuit/Open
Description: The engine control module (ECM) or powertrain control module (PCM) power relay control circuit has an open circuit.
Cause: Faulty relay, damaged wiring, or poor connections.
Symptoms: Intermittent or no engine operation, and a check engine light.
Location of Fault: ECM/PCM power relay control circuit.
How to Fix: Inspect and replace the faulty relay, repair damaged wiring, and ensure proper connections.
DTC P0301: Cylinder 1 Misfire Detected
Description: The engine control module has detected a misfire in cylinder 1.
Cause: Faulty spark plug, ignition coil, fuel injector, or mechanical issue.
Symptoms: Rough running, poor performance, and a check engine light.
Location of Fault: Cylinder 1 in the engine.
How to Fix: Inspect and replace the spark plug, ignition coil, or fuel injector for cylinder 1, and check for any mechanical issues.
DTC P1448: High Voltage Battery Module Voltage Sense Malfunction
Description: The high voltage battery module voltage sense circuit is malfunctioning.
Cause: Faulty voltage sensor, damaged wiring, or poor connections.
Symptoms: Reduced hybrid performance, decreased fuel efficiency, and a check engine light.
Location of Fault: High voltage battery module voltage sense circuit.
How to Fix: Inspect and replace the voltage sensor, repair damaged wiring, and ensure proper connections.
DTC P1449: High Voltage Battery Module Discharge Control Module (MCM) Reset
Description: The high voltage battery module’s discharge control module has reset.
Cause: Faulty discharge control module, damaged wiring, or poor connections.
Symptoms: Reduced hybrid performance, decreased fuel efficiency, and a check engine light.
Location of Fault: High voltage battery module discharge control module.
How to Fix: Inspect and replace the discharge control module, repair damaged wiring, and ensure proper connections.
DTC P1568: Battery Module Discharge Control Module (MCM) Communication Error
Description: The battery module’s discharge control module has a communication error.
Cause: Faulty discharge control module, damaged wiring, or poor connections.
Symptoms: Reduced hybrid performance, decreased fuel efficiency, and a check engine light.
Location of Fault: Battery module discharge control module.
How to Fix: Inspect and replace the discharge control module, repair damaged wiring, and ensure proper connections.
DTC P1570: Battery Module Discharge Control Module (MCM) Function Error
Description: The battery module’s discharge control module has a function error.
Cause: Faulty discharge control module or damaged wiring.
Symptoms: Reduced hybrid performance, decreased fuel efficiency, and a check engine light.
Location of Fault: Battery module discharge control module.
How to Fix: Inspect and replace the discharge control module and repair damaged wiring.
DTC P1167: Invalid Engine Speed Signal Detected
Description: The engine control module has detected an invalid engine speed signal.
Cause: Faulty crankshaft position sensor, damaged wiring, or poor connections.
Symptoms: Stalling, rough running, poor performance, and a check engine light.
Location of Fault: Crankshaft position sensor and its related wiring.
How to Fix: Inspect and replace the crankshaft position sensor, repair damaged wiring, and ensure proper connections.
DTC P1448: High Voltage Battery Module Voltage Sense Malfunction
Description: The high voltage battery module voltage sense circuit is malfunctioning.
Cause: Faulty voltage sensor, damaged wiring, or poor connections.
Symptoms: Reduced hybrid performance, decreased fuel efficiency, and a check engine light.
Location of Fault: High voltage battery module voltage sense circuit.
How to Fix: Inspect and replace the voltage sensor, repair damaged wiring, and ensure proper connections.
DTC P1576: Battery Module Discharge Control Module (MCM) Requested MIL Illumination
Description: The battery module discharge control module has requested the malfunction indicator light (MIL) to illuminate.
Cause: Faulty discharge control module, damaged wiring, or poor connections.
Symptoms: Reduced hybrid performance, decreased fuel efficiency, and a check engine light.
Location of Fault: Battery module discharge control module.
How to Fix: Inspect and replace the discharge control module, repair damaged wiring, and ensure proper connections.
DTC P1634: Battery Module Discharge Control Module (MCM) Communication Error
Description: The battery module’s discharge control module has a communication error.
Cause: Faulty discharge control module, damaged wiring, or poor connections.
Symptoms: Reduced hybrid performance, decreased fuel efficiency, and a check engine light.
Location of Fault: Battery module discharge control module.
How to Fix: Inspect and replace the discharge control module, repair damaged wiring, and ensure proper connections.
DTC P1648: High Voltage Battery Pack Voltage Sense Circuit Low Input
Description: The high voltage battery pack voltage sense circuit has a low input signal.
Cause: Faulty voltage sensor, damaged wiring, or poor connections.
Symptoms: Reduced hybrid performance, decreased fuel efficiency, and a check engine light.
Location of Fault: High voltage battery pack voltage sense circuit.
How to Fix: Inspect and replace the voltage sensor, repair damaged wiring, and ensure proper connections.
DTC P0174: System Too Lean (Bank 2)
Description: The air-fuel mixture in bank 2 is too lean, causing inefficient combustion.
Cause: Vacuum leaks, faulty mass air flow sensor, or malfunctioning fuel injectors.
Symptoms: Rough idling, hesitation, poor fuel economy, and a check engine light.
Location of Fault: Bank 2 of the engine, which includes the cylinders and associated components.
How to Fix: Inspect and repair any vacuum leaks, clean or replace the mass air flow sensor, and clean or replace fuel injectors.
DTC P0335: Crankshaft Position Sensor “A” Circuit Malfunction
Description: The engine control module has detected a malfunction in the crankshaft position sensor “A” circuit.
Cause: Faulty crankshaft position sensor, damaged wiring, or poor connections.
Symptoms: Stalling, rough running, poor performance, and a check engine light.
Location of Fault: Crankshaft position sensor “A” circuit.
How to Fix: Inspect and replace the crankshaft position sensor, repair damaged wiring, and ensure proper connections.
DTC P0340: Camshaft Position Sensor “A” Circuit Malfunction (Bank 1)
Description: The engine control module has detected a malfunction in the camshaft position sensor “A” circuit for bank 1.
Cause: Faulty camshaft position sensor, damaged wiring, or poor connections.
Symptoms: Stalling, rough running, poor performance, and a check engine light.
Location of Fault: Camshaft position sensor “A” circuit for bank 1.
How to Fix: Inspect and replace the camshaft position sensor, repair damaged wiring, and ensure proper connections.
DTC P0421: Warm-Up Catalyst Efficiency Below Threshold (Bank 1)
Description: The efficiency of the warm-up catalytic converter in bank 1 has dropped below the acceptable level.
Cause: A faulty catalytic converter, oxygen sensors, or a leak in the exhaust system.
Symptoms: Poor fuel economy, reduced performance, and a check engine light.
Location of Fault: Warm-up catalytic converter and its related oxygen sensors in the exhaust system for bank 1.
How to Fix: Inspect and replace the catalytic converter if needed, or replace faulty oxygen sensors.
DTC P0441: Evaporative Emission Control System Incorrect Purge Flow
Description: The evaporative emission control system purge flow is incorrect.
Cause: Faulty purge valve, damaged hoses, or a clogged vapor canister.
Symptoms: Check engine light.
Location of Fault: Evaporative emission control system, including purge valve, hoses, and vapor canister.
How to Fix: Inspect and replace the purge valve, repair or replace damaged hoses, and clean or replace the vapor canister.
WORDS FROM ME
Understanding the most common Diagnostic Trouble Codes for your Honda Insight is crucial for proper maintenance and troubleshooting. Familiarizing yourself with these 29 DTCs not only helps you diagnose issues in a timely manner but also allows you to communicate effectively with your mechanic. Remember, preventive maintenance is key to extending the life of your vehicle and avoiding costly repairs. Always consult a professional mechanic when unsure about any issue or procedure, and don’t hesitate to seek expert advice. By staying informed and proactive, you can ensure a smoother, more enjoyable driving experience with your Honda Insight.