Service Manual 75-90 HP E-TEC Engine Managment Module [External Sensors]

Supplies the EMM with barometric pressure reading to compensate for changes in altitude and air density.

If the BP sensor reads below 13.3 KPa or above 119.0 KPa, or the sensor or circuit fails, the EMM:

If the BP sensor reads below 70 KPa, the EMM:

If the BP sensor reads above 105 KPa, the EMM:

Sensor inputs and internal EMM controllers are used to control outboard operation. Use Evinrude Diagnostics software to troubleshoot the sensors. Refer to the EMM Service Code Chart at the back of this manual for a complete list of all engine fault codes.

The EMM provides a 5 V DC signal for sensor circuits. It monitors all sensor voltage inputs and compares them to predetermined acceptable ranges. Inputs that fall outside of the acceptable range create service codes.

Air Temperature Sensor

Monitors the air temperature at the throttle body. The air temperature sensor is a negative temperature coefficient (NTC) thermistor. As temperature increases, the resistance of the sensor decreases resulting in a lower voltage reading at the EMM. Temperature decreases result in a resistance increase and a higher voltage reading at the EMM.

If the AT sensor voltage is out of the expected range, or the sensor or circuit fails, the EMM:

Monitors cylinder head temperature. The sensor is a negative temperature coefficient thermistor (NTC).

If cylinder head temperature exceeds 212° F (100° C), the EMM:

If cylinder head temperature exceeds 248°F (120°C), the EMM:

The outboard will not restart after a temperature related SHUTDOWN until the engine temperature returns to normal. Refer to SHUTDOWN MODE on p. 94.

If sensor values are below -15°F (-26.1°C) or above 331°F (166.5°C), the EMM:

If sensor values are below -4°F (-20°C), the EMM:

If engine does not reach operating temperature on cylinder head (104°F / 40°C below 2300 RPM) in 10 minutes, the EMM:

The low oil switch monitors the oil level in the oil tank.

If the oil level falls below one-quarter capacity, the EMM signals:

When the oil level falls below one-quarter, the EMM begins counting oil pump pulse cycles. When it reaches 4800 pulses, the EMM:

To recover from S.A.F.E. mode, the oil pump must cycle for a minimum of three pulses with the oil level above one-quarter.

If outboard has been run for more than 3 hours with NO OIL faults (codes 34 & 117), the EMM .

The throttle position sensor is connected to the throttle plate shaft. The sensor receives a voltage signal from the EMM. As the throttle lever is rotated, the EMM receives a return voltage signal through a second wire. This signal increases as the TPS lever is advanced. A third wire provides a ground circuit back to the EMM.

Refer to TPS Calibration on p. 143.

If the TPS circuit reads above 0.78 volts when the key is turned to ON, or the recoil starter is pulled, the EMM:

If the outboard starts, the code is stored.

If code 11 is present as both a Hard Fault and a Stored Fault, refer to Control Cable Adjustments on p. 46.

If the TPS or TPS circuit fails (below 0.14 volts or above 4.92 volts), the EMM:

IMPORTANT: When a TPS circuit fault has been detected, the outboard will not accelerate above idle speed. To reset, stop the outboard and correct the fault.

If the TPS circuit reads below 0.2 volts, the EMM:

If the TPS circuit reads above 4.85 volts, the EMM:

The CPS is a magnetic device. It is mounted on the throttle body, next to the flywheel.

Ribs spaced on the flywheel mark crankshaft position. As the ribs pass the magnetic field of the CPS, an AC voltage signal is generated. The EMM uses this signal to identify crankshaft position and speed, generate a tachometer signal, and control fuel and ignition timing.

If the sensor is damaged or the signal is intermit tent (10 instances), the EMM:

Approximate air gap between CPS and flywheel ribs is .073 (1.85 mm).

Use the Evinrude Diagnostics software Monitor screen to check CPS operation. The software should show an RPM reading while the outboard is cranking. If the CPS or its circuit fails, no RPM reading will appear and the outboard cannot run.

The powerhead mounted neutral switch controls a ground signal from the EMM to indicate shift link age position. This allows the EMM to control idle speed variations for NEUTRAL or IN GEAR. Tiller models use the switch for start in gear protection. Fuel and ignition functions are turned off if the neutral switch is not closed.

If the starter is cranked while the outboard is in gear, or if the switch fails, the EMM:

The Monitor screen of the diagnostics software displays switch position, NEUTRAL or IN GEAR. Make sure switch is operating properly.