CONTROL SYSTEM (CONT’D) E-ECU (Cont’d)

Requirement

The table below shows the operating conditions of the E-ECU.

I/O Requirement

RegulationRated voltage12 VDC

Operating ambient temperature-30°C ~ 80°C

Storage ambient temperature-40°C ~ 110 °C

Basic PerformanceOperating voltage range10.0 ~ 16.0 VDC

Minimum operating voltage6.0 VDC Min.

VibrationSeverity levelTo be installed on a place of 45 or lower in severity level The acceleration, speed, and displacement of the ECU mount must conform to the requirements shown to the right in an overall range of 5 - 1000 Hz.

WaterproofnessWaterproofness (of connector)

Precautions:

70.4m/s (rms) Max.

44.6 mm/s (rms) Max. 0.283 mm (rms) Max. 0.800 mm (p.p) Max.

JIS D0203 S2 compliant

The ECU must not be installed with its connector facing upward.

•Install the E-ECU in a location that is not subject to steam or high-pressure water for cleaning.

•Install the E-ECU in a location that is well ventilated and not subject to direct sunlight.

•Install the E-ECU so that the connector faces downward. Failure to do so may trap water in the connector, resulting in corrosion of connector pins.

•Do not plug or unplug the connector for at least 6 seconds after the E-ECU is turned on or off.

•Do not touch connector pins with bare hands. Doing so may corrode or statically charge connector pins, resulting in damage to electronic components in the E-ECU.

•Do not force a measuring or testing probe into the female coupler of the connector. Repeated plugging/unplugging may cause contact failure of connector pins, resulting in malfunction of the E-ECU.

•Ensure no water is trapped inside the coupler when plugging or unplugging the connector. Water inside the coupler may corrode connector pins, resulting in malfunction of the E-ECU.

•Avoid plugging/unplugging the connector more than ten times. Repeated plugging/unplugging may cause contact failure of connector pins, resulting in malfunction of the E-ECU.

•Do not use the ECU that has suffered drop impact.

•When the machine is used in areas where a cryoprotectant/salt is distributed or near the seashore, the aluminum case of the E-ECU may corrode, resulting in malfunction of the E-ECU. Use a cover to protect the E-ECU against salt intrusion.

Current consumption

The engine control-related components including ECU, rack actuator, EGR valve, CSD, main relay, rack actuator relay, starter relay, starting aid relay, lamp, and switch require the current consumption of 4.6 [A] in measurement. Among these, the cold starter such as CSD requires the current consumption of 1A, so select the alternator capacity of 5A for frequent cold starts or 4A for otherwise.

CONTROL SYSTEM (CONT’D)

E-ECU (Cont’d)

Minimum operating voltage

The minimum operating voltage of the E-ECU is 6.0 VDC. Decreasing the E-ECU power supply voltage to less than the above causes the ECU to stop. When the power supply voltage is recovered, it restarts from the initial condition.

When the battery voltage decreases to less than 6.0 V repeatedly at compression steps during cranking in cold start conditions, for example, the engine may not be able to start. To avoid such a trouble, check the battery and E-ECU power supply for correct voltage.

[Figure 10-20-6] provides the transition of the E-ECU power supply voltage at engine start.

Figure 10-20-6

Minimum detectable speed

The minimum detectable speed of the engine that can detect E-ECU and fuel injection pump (speed sensor) is set lower than the minimum cranking speed (average engine speed = 75min-1) required for starting the engine. However, when the engine speed is reduced at the starting time and not reaching the minimum detectable speed due to having drastically increased engine start load at the time of extremely low temperature or having the reduced battery capacity because of deterioration and electrical discharge, the E-ECU may indicate the speed sensor failure.For this case, increase the starter start current to decrease the engine start load.

Number of start/stop cycles and duration of energization

The E-ECU saves engine logs in the internal EEPROM and updates them every time the power turns off if the power self-holding feature (described later) is enabled, or at regular intervals if the power self-holding feature is disabled. The design service life of the E-ECU is therefore dependent on the maximum number of EEPROM write cycles.

The service life of EEPROM is limited to the order of 105 key-on operations if the power self-holding feature is enabled, or 104 key-on duration hours if the power self-holding feature is disabled.

EEPROM is a nonvolatile storage; data stored in EEPROM is not lost if the E-ECU power turns off.