Toyota 4Runner: Definition Of Terms

Monitor description

Description of what the ECM monitors and how it detects malfunctions (monitoring purpose and its details).

Related DTCs

Group of diagnostic trouble codes that are output by the ECM based on the same malfunction detection logic.

Typical enabling condition

Preconditions that allow the ECM to detect malfunctions.

With all preconditions satisfied, the ECM stores the DTC when the monitored value(s) exceeds the malfunction threshold(s).

Sequence of operation

The priority order that is applied to monitoring if multiple sensors and components are used to detect the malfunction.

While a sensor is being monitored, the next sensor or component will not be monitored until the previous monitoring has concluded.

Required sensor/components

The sensors and components that are used by the ECM to detect malfunctions.

Frequency of operation

The number of times that the ECM checks for malfunctions per driving cycle.

"Once per driving cycle" means that the ECM detects the malfunction only one time during a single driving cycle.

"Continuous" means that the ECM detects the malfunction every time the enabling condition is met.

Duration

The minimum time that the ECM must detect a continuous deviation in the monitored value(s) before storing a DTC. This timing begins after the "typical enabling conditions" are met.

Malfunction thresholds

Beyond this value, the ECM will conclude that there is a malfunction and store a DTC.

MIL operation

MIL illumination timing after a defect is detected.

"Immediate" means that the ECM illuminates the MIL the instant the ECM determines that there is a malfunction.

"2 driving cycles" means that the ECM illuminates the MIL if the same malfunction is detected again in the 2nd driving cycle.

Component operating range

Normal operation range of sensors and solenoids under normal driving conditions.

Use these ranges as a reference.

They cannot be used to judge if a sensor or solenoid is defective or not.