Description
Hint:
A direct ignition system (dis) is used on this vehicle.
The dis is a 1-cylinder ignition system in which each cylinder is ignited by one ignition coil and one spark plug is connected to the end of each secondary wiring. A powerful voltage, generated in the secondary wiring, is applied directly to each spark plug. The sparks of the spark plugs pass from the center electrode to the ground electrodes.
The ecm determines the ignition timing and transmits the ignition (igt) signals to each cylinder. Using the igt signal, the ecm turns the power transistor inside the igniter on and off. The power transistor, in turn, switches on and off the current to the primary coil. When the current to the primary coil is cut off, a powerful voltage is generated in the secondary coil. This voltage is applied to the spark plugs, causing them to spark inside the cylinders. As the ecm cuts the current to the primary coil, the igniter sends back an ignition confirmation (igf) signal to the ecm, for each cylinder ignition.
Reference: inspection using an oscilloscope.
While cranking or idling the engine, check the waveform between terminals igt (1
to 4) and e1, and igf1
and e1 of the ecm connector.
Monitor description
If the ecm does not receive any igf signals despite transmitting the igt signal, it interprets this as a fault in the igniter and sets a dtc.
If the malfunction is not repaired successfully, a dtc is set 1 second after the engine is next started.
Monitor strategy
Typical enabling conditions
Typical malfunction thresholds
Component operating range
Wiring diagram
Inspection procedure
Hint:
Read freeze frame data using the intelligent tester. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
Standard resistance (check for open)
Standard voltage
Standard
resistance (check for open)
Standard resistance (check for open)
Standard resistance (check for short)
Standard resistance (check for short)
Notice:
Do not shuffle the connectors.
Lower instrument panel
Precaution
Precaution for vehicle with srs airbag and
seat belt pretensioner
Some operations in this section may affect the srs
airbags and seat belt pretensioner. Prior to
performing the corresponding operations, read the
srs airbag notice (see page rs-1).
Components
...
Customize parameters
Notice:
When the customer requests a change in a function,
first make sure that the function can be customized.
Make a note of the current settings before
customizing.
When troubleshooting a function, first make sure that
the function is set to the default setting.
Combination me ...
Intake air temperature circuit malfunction
Description
The intake air temperature (iat) sensor, mounted on the mass air flow (maf)
meter, monitors the iat.
The iat sensor has a built-in thermistor with a resistance that varies according
to the temperature of the
intake air. When the iat is low, the resistance of the thermist ...