
CAUTION
- If the engine is running
Turn off the engine and ensure that there is adequate ventilation before performing maintenance checks.
Vehicle interior
Emission inspection and maintenance (I/M) programsCatalyst System Efficiency Below Threshold (Bank 1) (P0420)
MONITOR DESCRIPTION
The ECM uses sensors mounted in front of and behind the Three-Way Catalytic Converter
(TWC) to monitor its efficiency.
The first sensor, the air fuel ratio sensor, sends pre-catalyst information to
the ECM. The second sensor, the heat ...
Problem Symptoms Table
PROBLEM SYMPTOMS TABLE
HINT:
Use the table below to help determine the cause of problem symptoms.
If multiple suspected areas are listed, the potential causes of the symptoms
are listed in order of probability in the "Suspected Area" ...
Precaution
PRECAUTION
1. PRECAUTION FOR DISCONNECTING CABLE FROM NEGATIVE BATTERY TERMINAL
NOTICE:
When disconnecting the cable from the negative (-) battery terminal, initialize
the following system after the terminal is reconnected:
System Name
...