Pin Voltage Charts

Fig 1: Connector Pin Identification

DME/MOTRONIC CONTROL UNIT PIN ASSIGNMENTS (2.5L M50 ENGINE) ⁽¹⁾

Pin No.

Function/Description

Signal Type Or Voltage Value

Fuel Pump Relay & Crankshaft/ Speed Sensor

⁽²⁾⁽³⁾ Superimposed Ground And Speed Signal Output

Idle Speed Actuator (Close)

Zero Volts Or Ground (Output Signal)

Fuel Injector (No. 1)

Pulse (Duty Cycle) Duration In % (Output Signal)

Fuel Injector (No. 3)

Pulse (Duty Cycle) Duration In % (Output Signal)

Fuel Injector (No. 2)

Pulse (Duty Cycle) Duration In % (Output Signal)

Fuel Injectors (Ground)

Ground Circuit

CHECK ENGINE Light

⁽⁴⁾ Ground Ckt. (Output Signal)

Throttle Potentiometer (TPS)

Electronic Transmission Control(EGS) Square Wave Output Signal

Throttle Potentiometer (TPS)

⁽⁵⁾ 0.5-5.0 Volts(Input Signal)

Air Mass Sensor (Wire Burn Off)

⁽⁶⁾ Voltage On For One Second (Output Signal)

Air Mass Sensor

Ground Circuit

Camshaft Sensor

⁽⁷⁾ AC Voltage (Input Signal)

Instrument Cluster (Fuel Consumption)

Square Wave Output Signal

Ignition Coil (Cylinder No. 2)

Primary Circuit Output Signal

Ignition Coil (Cylinder No. 3)

Primary Circuit Output Signal

Ignition Coil (Cylinder No. 1)

Primary Circuit Output Signal

Battery Voltage (Permanent)

⁽⁸⁾ 12 Volts (Battery Voltage Input)

DME Master Relay

⁽⁹⁾ Output Signal

Sensors (Shield Wire)

Ground Circuit

Idle Speed Actuator (Open)

Zero Volts Or Ground (Output Signal)

Fuel Injector (No. 5)

Pulse (Duty Cycle) Duration In % (Output Signal)

Fuel Injector (No. 6)

Pulse (Duty Cycle) Duration In % (Output Signal)

Fuel Injector (No. 4)

Pulse (Duty Cycle) Duration In % (Output Signal)

Ground (Except Injectors & Ignition)

Ground Circuit

Fuel Tank Vent (Evaporation) Control

⁽¹⁰⁾ Pulse (Duty Cycle) Duration In % (Output Signal)

Oxygen Sensor Heater Relay

Output Signal (W/Ignition On)

Air Mass Sensor

0-5 Volts Input Signal

Temperature Sensor (Ground)

Ground Circuit

Camshaft Sensor

⁽⁷⁾ AC Voltage (Input Signal)

A/C Compressor Shutoff

⁽¹¹⁾ Output Signal

Ignition Coil (Cylinder No. 4)

Primary Circuit Output Signal

Ignition Coil (Cylinder No. 6)

Primary Circuit Output Signal

Ignition Coil (Cylinder No. 5)

Primary Circuit Output Signal

Battery Voltage

⁽⁸⁾ 12 Volts (Battery Voltage Input)

Ignition (Ground)

Ground Circuit

Start (Ignition) Input

12 Volts (Battery Voltage Input)

Air Mass (Throttle Valve) Sensor

5-Volt (Reference) Output Signal

Programming Voltage

⁽¹²⁾ Voltage (Input Signal)

Ignition Timing Intervention

⁽¹³⁾ Ground Circuit (Input Signal)

Park/Neutral Switch

⁽¹⁴⁾ Input Signal

Crankshaft/Speed Sensor

AC Voltage (Input Signal)

Crankshaft/Speed Sensor

AC Voltage (Input Signal)

Oxygen Sensor

0.1-1.2 Volts (Input Signal)

Oxygen Sensor (Ground)

Ground Circuit

Vehicle Speed Signal

Square Wave Input Signal

Engine Speed Signal

Ignition Interval (TD) Output Signal

Intake Air Temperature Sensor

0-5 Volts (Input Signal)

Engine (Coolant) Temp. Sensor

0-5 Volts (Input Signal)

Anti-Theft Alarm Switch

⁽¹⁵⁾ 12 Volts (Battery Voltage Input)

A/C Compressor

⁽¹⁶⁾ 12 Volts (Battery Voltage Input)

A/C Switch

⁽¹⁷⁾ 12 Volts (Battery Voltage Input)

Diagnostic Initiation Line (RxD)

⁽¹⁸⁾ 12 Volts (Battery Voltage Input)

Diagnostic Data Line (TxD)

⁽¹⁸⁾ Input/Output Signal

⁽¹⁾	Pin assignments not listed are not used (blank).

⁽²⁾	Ground output signal from control unit. Output signal can only be measured with crankshaft rotating at normal engine speed.

⁽³⁾	Superimposed with fuel pump ground circuit. Speed signal is generated once each revolution.

⁽⁴⁾	In case of defect, check CHECK ENGINE light function with ignition on.

⁽⁵⁾	Voltage signal input to control unit will vary depending on throttle position.

⁽⁶⁾	Output signal is sent 4 seconds after engine is turned off.

⁽⁷⁾	Once per camshaft revolution.

⁽⁸⁾	No DME functions if voltage is not present.

⁽⁹⁾	No DME functions when master relay is off. Connect jumper wire between terminals No. 30 and 87.

⁽¹⁰⁾	Duty cycle depends on engine speed and load.

⁽¹¹⁾	Output signal to A/C relay only at speed of 5 MPH and engine at full load.

⁽¹²⁾	Only activated during programming.

⁽¹³⁾	Input signal from electronic transmission control (EGS) unit. Only active during gearshifts.

⁽¹⁴⁾	Gear selector lever in PARK or NEUTRAL position.

⁽¹⁵⁾	With anti-theft alarm activated (armed).

⁽¹⁶⁾	With A/C compressor clutch engaged.

⁽¹⁷⁾	With A/C system on.

⁽¹⁸⁾	With diagnostic socket cover closed.