Engine Controls - Pin Voltage Charts: Introduction
Pin voltage charts are supplied to reduce diagnostic time. Checking pin voltages at the DME/Motronic control unit determines whether it is receiving and transmitting proper voltage signals. Charts may also help determine if control unit wiring harness is shorted or opened.
NOTE:
Unless stated otherwise in testing procedures, perform all voltage tests using a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance. Voltage readings may vary slightly due to battery condition or charging rate.
DME/MOTRONIC CONTROL UNIT PIN ASSIGNMENTS (1)
(535i - 3.5L M30 ENGINE; DME 1.3)
| Pin No. | Function/Description | (2) Signal Type Or Voltage Value | ||||
|---|---|---|---|---|---|---|
| 1 | Ignition Coil (Terminal No. 1) | 150 Volts, 0.2 Amps Maximum (Output Signal) | ||||
| 2 | Ignition (Ground) | Ground Circuit | ||||
| 3 | Fuel Pump Relay & Crankshaft/Speed Sensor | Output Signal | ||||
| 4 | Idle Speed Control Valve (Open) | Output Signal | ||||
| 5 | Fuel Tank (Evaporation) Control | Output Signal | ||||
| 6 | Engine Speed Signal | Ignition Interval (TD) Output Signal | ||||
| 7 | Airflow Sensor | Input Signal | ||||
| 8 | Cylinder Identification Sensor | Input (Positive +) Signal | ||||
| 10 | Oxygen Sensor (Ground) | Ground Circuit (Potential Free) | ||||
| 12 | Airflow Sensor | Output Signal | ||||
| 13 | Diagnostic Initialization Line (RxD) | Input Signal | ||||
| 14 | Injectors (Ground) | Ground Circuit | ||||
| 15 | CHECK ENGINE Light | Output Signal | ||||
| 16 | Injectors (No. 1, 3 & 5) | Output Signal | ||||
| 17 | Injectors (No. 2, 4 & 6) | Output Signal | ||||
| 18 | Battery Voltage (Permanent) | 12 Volts (Battery Voltage Input) | ||||
| 19 | Ground (Injectors & Ignition) | Ground Circuit | ||||
| 22 | Idle Speed Control Valve (Close) | Output Signal | ||||
| 24 | Ground (Except Injectors & Ignition) | Ground Circuit | ||||
| 26 | Airflow Sensor (Ground) | Ground Circuit | ||||
| 27 | Ignition Coil (Terminal No. 15) | Input Signal | ||||
| 28 | Oxygen Sensor | Input Signal | ||||
| 29 | Engine Speed Signal | Input Signal From Instrument Cluster | ||||
| 31 | Cylinder Identification Sensor | Ground (Negative -) Circuit (Potential Free) | ||||
| 32 | Instrument Cluster (Fuel Consumption) | Square Wave Output Signal | ||||
| 33 | Kickdown Inhibit | Ouput Signal (Automatic Transmission Only) | ||||
| 36 | DME Master Relay | Output Signal | ||||
| 37 | DME Master Relay (Supply) | Input Signal | ||||
| 38 | Anti-Theft Alarm Switch | Input Signal | ||||
| 39 | Programming Voltage | 12 Volts (Battery Voltage Input) | ||||
| 40 | A/C Compressor | Input Signal | ||||
| 41 | A/C Switch | Input Signal | ||||
| 42 | Park/Neutral Switch | Input Signal (Automatic Transmission Only) | ||||
| 44 | Intake Air Temp. Sensor | Input Signal | ||||
| 45 | Engine (Coolant) Temp. Sensor | Input Signal | ||||
| 47 | Pulse Sensor Signal | Input (Positive +) (Inductive) | ||||
| 48 | Pulse Sensor Signal | Input (Negative -) (Inductive) | ||||
| 50 | Engine Drag/Torque Control | Input Signal | ||||
| 51 | Ignition Timing Control | Input Signal (Automatic Transmission Only) | ||||
| 52 | Idle Speed Signal | Input Signal | ||||
| 53 | Full Load (WOT) Signal | Input Signal | ||||
| 54 | Torque Converter Control | Input Signal (Automatic Transmission Only) | ||||
| 55 | Diagnostic Data Line (TxD) | Input/Output Signal | ||||
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