MBE 900 4000 Troubleshooting – Section 2.7 Sensors

Section 2.7
Sensors

The MBE Electronic Controls system is designed to operate with several types of sensors as listed in Table "Sensor Types" .‪

Sensor Type‪	Description‪
Variable Reluctance/Magnetic Pick-up‪	Used to monitor the crankshaft position, engine speed, turbo speed (MBE 4000 only), and vehicle speed.‪
Thermistor‪	Used to monitor temperatures.‪
Variable Capacitance‪	Used to monitor manifold, and oil gallery pressures.‪
Variable Resistance (Potentiometer)‪	Used to sense throttle position.‪
Switch‪	Used to signal coolant level, inlet air restriction, and oil level.‪

The sensors integrated into the Engine Harness are factory-installed (refer to "2.7.1 Factory-Installed Sensors" ). The sensors integrated into the Vehicle Interface Harness are installed by the OEM (refer to "2.7.2 OEM Installed Sensors" ).‪

Section 2.7.1
Factory-Installed Sensors

The sensors integrated into the factory-installed Engine Harness are listed in Table "Function of Factory-Installed Sensors" .‪

Sensor‪	Function‪
Camshaft Position Sensor‪	Senses camshaft position and engine speed for functions such as fuel control strategy.‪
Crankshaft Position Sensor‪	Indicates specific cylinder positions and engine speed.‪
Engine Coolant Temperature Sensor (ECT Sensor)‪	Senses coolant temperature for functions such as engine protection, fan control and engine fueling.‪
Engine Oil Level Sensor‪	Senses oil level for functions such as engine protection.‪
Engine Oil Pressure Sensor‪ (EOP Sensor)‪	Senses gallery oil pressure for functions such as engine protection.‪
Engine Oil Temperature Sensor‪ (EOT Sensor)‪	Senses oil temperature for functions such as reducing variation in fuel injection and fan control.‪
Intake Manifold Pressure Sensor‪ (IMP Sensor)‪	Senses turbo boost for functions such as smoke control and engine protection.‪
Intake Manifold Temperature Sensor‪ (IMT Sensor)(IMT Sensor)‪	Senses boost temperature‪
Supply Fuel Temperature Sensor‪ (SFT Sensor)‪	Senses fuel temperature for functions such as engine fueling.‪
Turbo Speed Sensor‪ (MBE 4000 only)‪	Monitors turbo speed.‪

See Figure "Sensor Location on the MBE900 Non-EGR Engine" for sensor locations on the MBE 900 engine‪

Note: The 6–cylinder engine is shown; sensor locations are similar on the 4–cylinder engine.

Note: The Barometric Pressure Sensor (BARO Sensor) is integrated into the PLD-MR control unit.

Note: The EOL Sensor, if used, is located at the bottom of the oil pan.

1. Oil Combination Sensor‪	5. Barometric Pressure Sensor (integrated into PLD-MR)‪
2. Engine Coolant Temperature Sensor‪	6. Camshaft Position Sensor (on camshaft)‪
3. Boost Air Combination Sensor‪	7. Crankshaft Position Sensor (on timing case)‪
4. Supply Fuel Temperature Sensor‪	‪

Figure 1. Sensor Location on the MBE 900 Engine

Two sensors are not easily visible from the left-hand side of the MBE 4000 engine. The Boost Air Combination Sensor is located on the right-hand side of the charge air manifold, behind the No. 2 cylinder head. The Oil Combination Sensor is located at the base of the oil filter. See Figure "Sensor Location on the MBE 4000 Engine" for sensor locations on the MBE 4000 engine.‪

Note: The EOL Sensor, if used, is located at the bottom of the oil pan.

1. Boost Air Combination Sensor‪	5. Barometric Pressure Sensor (integrated into PLD-MR)‪
2. Camshaft Position Sensor (on camshaft)‪	6. Supply Fuel Temperature Sensor‪
3. Crankshaft Position Sensor‪	7. Oil Combination Sensor‪
4. Engine Coolant Temperature Sensor‪	‪

Figure 2. Sensor Location on the MBE 4000 Engine

Section 2.7.2
OEM Installed Sensors

All sensors must be of the proper type and continuously monitor vehicular and environmental conditions, so the PLD-MR can react to changing situations.‪

The OEM is responsible for installing the sensors listed in Table "Function and Guidelines for OEM-installed Sensors" .‪

Sensor‪	Part Number‪	Function‪
Engine Coolant Level Sensor (ECL Sensor)‪	23522855‪ 23520380‪ 23520381‪	Senses coolant level for engine protection. Refer to "2.7.3 Engine Coolant Level Sensor" .‪
Vehicle Speed Sensor (VSS)‪	--‪	Senses vehicle speed for Cruise Control and Vehicle Speed Limiting. Refer to "2.7.4 Vehicle Speed Sensor" .‪

* Available in some applications

Note: The OEM harness must be securely fastened every 150 mm (6 in.). It is required that the harness be fastened within 150 mm (6 in.) of the sensor.

Section 2.7.3
Engine Coolant Level Sensor

The ECL Sensor provides an input to the engine protection system and warn the operator if a low coolant level has been reached. Other non-DDC supplied engine coolant level sensors may be used but may require the use of a signal interface.‪

The main component of the ECL Sensor consists of a conductivity probe, which connects to the DDEC-VCU (see Figure "Engine Coolant Level Sensor Specifications" ).‪

NOTICE:
The probe has an operational temperature range of -40 to 125°C (-40 to 257°F). Exposure to temperatures beyond this range may result in unacceptable component life, or degraded sensor accuracy.‪

Figure 3. Engine Coolant Level Sensor Specifications

‪

The connector listed in Table "Metri-Pack 280 Connectors and Part Numbers" is a Metri-Pack 280 series push-to-seat connector. ‪

Coolant Level Sensor Connector‪
Connector‪	P/N: 15300027‪
Terminal‪	P/N: 12077411‪
Seal‪	P/N: 12015323‪
Secondary Lock‪	P/N: 15300014‪

The OEM must connect the ECL Sensor probe as shown in the next illustration (see Figure "Engine Coolant Level Sensor Installation" ). Polarity of the ground and signal must be correct for proper operation.‪

Figure 4. Engine Coolant Level Sensor Installation

‪

The probe should be located in either the radiator top tank or a remote mounted surge tank. It should be mounted horizontally in the center of the tank and must be in a position to signal low coolant before aeration occurs. Typically, this is a height representing 98% of the drawdown quantity. The probe should be located so that it is not splashed by deaeration line, stand pipe or coolant return line flows. The insulated portion of the probe should be inserted into the coolant 15 mm (0.5 in.) or more past the inside wall of the tank. See Figure "Engine Coolant Level Sensor Location - Top of Radiator Tank" .‪

Figure 5. Engine Coolant Level Sensor Location - Top of Radiator Tank

‪

Determine proper location for low coolant level sensor while running the drawdown test. It must actuate a warning before the satisfactory drawdown level is reached.‪

The ECL Sensor components are OEM supplied hardware and can be purchased as kits or individual components, depending on OEM requirements.‪

The following kits listed in Table "Engine Coolant Level Sensor Installation Kit P/N 23515397 (1/4 in. NPTF)" and Table "Engine Coolant Level Sensor Installation Kit P/N 23515398 (3/8 in. NPTF)" provide all the necessary hardware for proper installation of the ECL Sensor. Kits are available through the DDC parts distribution network.‪

Component‪	Part Number‪
ECL Sensor‪	23520380‪
Metri-Pack Connector Kit‪	15300027‪
Metri-Pack Terminals‪	12077411‪
Secondary Lock‪	15300014‪
Wire Seal‪	12015323‪
Terminal‪	12103881‪

Component‪	Part Number‪
ECL Sensor‪	23520381‪
Metri-Pack Connector Kit‪	15300027‪
Metri-Pack Terminals‪	12077411‪
Secondary Lock‪	15300014‪
Wire Seal‪	12015323‪
Terminal‪	12103881‪

The sensor must be enabled with VEPS or the minidiag2 as listed in Table "Enabling the Engine Coolant Level Sensor" .‪

Parameter‪	Range‪	Default‪	Parameter ID‪
Enable ECL Sensor Input‪	0 = Disabled‪ 1 = Enabled‪	1‪	1 13 02‪

Section 2.7.4
Vehicle Speed Sensor

The DDEC-VCU can calculate vehicle speed, providing that it is properly programmed and interfaced with a Vehicle Speed Sensor (VSS) that meets MBE requirements. The VSS (see Figure "Vehicle Speed Sensor" ) provides a vehicle speed signal for use in Cruise Control and Vehicle Speed Limiting. The VSS signal type can be changed with the VEPS, or minidiag2.‪

Note: DDC does not approve of the use of signal generator sensors.

Figure 6. Vehicle Speed Sensor

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Section 2.7.4.1
SAE J1939 Data Link

A VSS wired to the DDEC-VCU is not required if the transmission output shaft message is being transferred over the SAE J1939 data link. To obtain accurate vehicle mileage, the parameters listed in Table "Vehicle Speed Sensor Parameters" must be programmed with VEPS or the minidiag2.‪

Parameter‪	Range‪	Default‪	Parameter ID‪
VSS Input Configuration‪	3 = Transmission output shaft on the SAE J1939 Data Link*‪	0 = No VSS‪	1 13 08‪
Axle Ratio‪	1 – 20.0‪	5.29‪	1 13 09‪
Number of Output Shaft Teeth‪	0 – 250‪	16‪	1 13 10‪
Tire Revs/Kilometer‪	160 – 1599‪	312‪	1 13 11‪
Top Gear Ratio‪	0.1 – 2.55‪	1‪	1 13 12‪
Two Speed Axle — Second Axle Ratio‪	1 – 20.0‪	5.29‪	1 13 13‪

* Range must be set to 1.

Section 2.7.4.2
Magnetic Pickup

The magnetic pickup requirements are listed in Table "Magnetic Pickup Vehicle Speed Sensor Requirements" . Magnetic Pickup size is determined by installation requirements. ‪

Parameters‪	Range‪
Frequency Range‪	1 - 3000 Hz‪
Low Threshold Voltage‪	>1.7 Volts‪

The VSS is wired to the 15-pin connector of the DDEC-VCU. The VSS pin wiring is listed in Table "Vehicle Speed Sensor Wiring" .‪

Connector/Pin‪	Function‪
15/3‪	VSS (+)‪
15/4‪	VSS (-)‪

Magnetic Vehicle Speed Sensors can be obtained from the following sources:‪

• Wabash Technologies 1375 Swan StreetHuntington, Indiana 46750-0829Tel: 260-356-8300www.wabashtech.com
• Airpax Instruments Phillips Technologies150 Knotter DriveChesire, Connecticut 06410Tel: 800-643-0643
• Invensys Electro Corporation 1845 57th StreetSarasota, Florida 34231Tel: 1–800–446–5762Fax: 941-355-3120www.electrocorp.com

Section 2.7.4.3
SAE J1939 Data Link

A VSS wired to the DDEC-VCU is not required if the transmission output shaft speed message is being transmitted over the SAE J1939 Data Link. To obtain accurate vehicle mileage, the parameters listed in Table "Vehicle Speed Sensor Parameters" must be programmed with VEPS or the minidiag2. ‪

Parameter‪	Range‪	Default‪	Parameter ID‪
VSS Input Configuration‪	3 = Transmission output shaft speed on the SAE J1939 Data Link*‪	0 = No VSS‪	1 13 08‪
Axle Ratio‪	1 – 20.0‪	5.29‪	1 13 09‪
Tire Revs/Kilometer‪	160 – 1599‪	312‪	1 13 11‪
Top Gear Ratio‪	0.1 – 2.55‪	1‪	1 13 12‪
Two Speed Axle — Second Axle Ratio‪	1 – 20.0‪	5.29‪	1 13 13‪

* Range must be set to 3.