Hint:
Use the table below to help determine the cause of the problem symptom. The potential causes of the symptoms are listed in order of probability in the "suspected area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.

Operation check
Terminals of ecuHow to proceed with troubleshooting
Notice:
Dtcs for the can communication system are as
follows: u0073, u0100, u0105, u0121, u0122, u0123,
u0124, u0126, u0129, c1280, c1296, c1297, and
b1499.
Refer to the troubleshooting procedures of each
system if dtcs regarding the can communication
system are not output.
Turn th ...
System voltage
Description
The battery supplies electricity to the ecm even when the ignition switch is
in the off position. This
power allows the ecm to store data such as dtc history, freeze frame data and
fuel trim values. If the
battery voltage falls below a minimum level, the memory is cleared and ...
Mass or volume air flow circuit
Description
The mass air flow (maf) meter is a sensor that measures the amount of air
flowing through the throttle
valve.
The ecm uses this information to determine the fuel injection time and to
provide the appropriate air-fuel
ratio.
Inside the maf meter, there is a heated platinu ...