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1992 BMW 735i

Trouble Code Definition

1992 BMW 735iSECTION Trouble Code Definition
FAULT CODE IDENTIFICATION - 535i, 735i & 735iL (DME 1.3)

Fault Codes Affected Circuit Probable Cause
1 DME/Motronic Control Unit Internal Self-Test Detected Program Error/Sequence In Control Unit
3 Fuel Pump Relay Shorted Relay Or Circuit To DME Control Unit Pin No. 3
4 Idle Speed Actuator (Open) (1) Shorted/Open Circuit In Idle Speed Actuator Or Circuit Wiring
5 Fuel Tank Vent (Evaporation) Control Shorted Circuit In Fuel Tank Vent Valve Or Its Circuit Wiring
7 Airflow (Sensor) Meter Shorted/Open Circuit In Airflow Sensor Or Its Circuit Wiring, Or Sensor Out Of Range
10 Oxygen (Sensor) Control (2) Sensor Out Of Range (Mixture TooLean/Rich For Longer Than 10 Seconds)
15 CHECK ENGINE Light Shorted Circuit On Indicator Light Or Its Circuit Wiring
16 Fuel Injectors (No. 1, 3 & 5) (3) Shorted/Open Circuit On Fuel Injectors Or Their Circuit Wiring
17 Fuel Injectors (No. 2, 4 & 6) (3) Shorted/Open Circuit On Fuel Injectors Or Their Circuit Wiring
22 Idle Speed Actuator (Close) (1) Shorted/Open Circuit In Idle Speed Actuator Or Its Circuit Wiring
28 Oxygen Sensor Shorted/Open Circuit On Oxygen Sensor Or Its Circuit Wiring
29 Vehicle (Road) Speed Sensor (4) Faulty Speed Sensor Input Signal
33 Kickdown Prevent Shorted Circuit In Kickdown Solenoid Valve Or Its Circuit Wiring
37 DME Power Supply (5) Voltage To DME Control Unit Drops To Less Than 9 Volts Or Exceeds 16 Volts
38 Anti-Theft (DWA) Signal Short To Battery Voltage In Circuit To DME Control Unit Pin No. 38
40 A/C Compressor (6) Open Circuit On Pin No. 41 And Short To Battery On Pin No. 40
44 Intake Air Temp. Sensor (7) Shorted/Open Circuit In Sensor Or Its Circuit Wiring
45 Engine (Coolant) Temp. Sensor Shorted/Open Circuit In Sensor Or Its Circuit Wiring
(1) When fault Code 22 is also stored, cause can be attributed to both windings in idle speed actuator. Fault Codes 4 and 22 are also stored when engine operation is interrupted without ignition being switched off. Such a defect is indicated by operating status. Code(s) can be ignored below 600 RPM.
(2) Check for incorrect fuel pressure, clogged injectors, defective engine (coolant) temperature sensor, leaks in air intake duct or defective fuel evaporation control system.
(3) A short circuit in one fuel injector or its circuit wiring causes entire group to be deactivated.
(4) Code is set when engine speed is greater than 4500 RPM, engine load greater than 3.0 milliseconds and vehicle speed less than 3-5 MPH.
(5) Loss of or incorrect voltage signal may be due to poor connections, high resistance, incorrect alternator belt tension or a defective alternator or voltage regulator.
(6) Code is set when DME control unit simultaneously receives battery voltage on pin No. 40 and zero volts on pin No. 41.
(7) Fault must be present for at least 30 seconds for code to set.
FAULT CODE IDENTIFICATION - 318 SERIES (DME 1.7)

Fault Codes Affected Circuit Probable Cause
1 Fuel Pump Relay (1) Shorted Relay Or Circuit To DME Control Unit Pin No. 1
3 Fuel Injectors (No. 1 & 3) (2) Shorted/Open Circuit In Fuel Injectors Or Their Circuit Wiring
8 CHECK ENGINE Light Shorted Circuit On Indicator Light Or Its Circuit Wiring
12 Throttle Potentiometer (TPS) Shorted/Open Circuit In Sensor Or Its Circuit Wiring
16 Camshaft Sensor Faulty Signals From Camshaft Sensor At 2500 RPM
29 Idle Speed Control Shorted Circuit In Wiring To DME Control Unit Pin No. 29
32 Fuel Injectors (No. 2 & 4) Shorted/Open Circuit In Fuel Injectors Or Their Circuit Wiring
36 Fuel Tank Venting Valve Shorted/Open Circuit On Fuel Tank Venting Valve Or Its Circuit Wiring
37 Oxygen Sensor Heater Relay Shorted/Open Relay Or Circuit To DME Control Unit Pin No. 37
41 Airflow Sensor Shorted/Open Circuit On Airflow Sensor Or Its Circuit Wiring Or Sensor Out Of Range
54 DME Power Supply (3) Voltage To DME Control Unit Drops To Less Than 9 Volts Or Exceeds 16 Volts
70 Oxygen Sensor (4) Shorted/Open Circuit On Oxygen Sensor Or Its Circuit Wiring
73 Speed Sensor (Signal) (5) Faulty Speed Sensor Input Signal
77 Intake Air Temp. Sensor (6) Shorted/Open Circuit On Sensor Or Its Circuit Wiring
78 Engine (Coolant) Temp. Sensor Shorted/Open Circuit On Engine Temp. Sensor Or Its Circuit Wiring
85 A/C Compressor (7) Open Circuit On Pin No. 86 And Short To Battery On Pin No. 85
100 Final Stage (Output Signal) Loose Connection On Final Stage Output Signal
200 DME Control Unit Faulty DME Control Unit Memory Modules
201 Oxygen Sensor Control Rich Or Lean Air/Fuel Mixture For At Least 8 Seconds
(1) Fault is recognized only when at least one additional final stage (output signal) is faulty.
(2) Injector group is deactivated with a short circuit in either injector or its power supply wiring. Cylinders No. 2 and 4 remain in operation.
(3) Check connections and wiring harness for resistance, incorrect alternator belt tension and defective alternator or voltage regulator.
(4) Engine coolant temperature must be at least 158°F (70°C) and an engine load signal must be 4.5 milliseconds for at least 5 seconds.
(5) Fault is set when engine speed is 4500 RPM, engine load signal is 4.0 milliseconds and vehicle speed is 3-5 MPH.
(6) Recognition of an open circuit requires at least 3 minutes time after starting engine and an idle speed for 30 seconds (minimum).
(7) Fault is set when DME control unit simultaneously receives battery voltage on pin No. 85 and zero volts on pin No. 86.
FAULT CODE IDENTIFICATION - 325 SERIES & 525i (DME 3.1)

Fault Codes Affected Circuit Probable Cause
0 Undefined Defect (1) Undefined Defect Code Has Been Stored In Defect Code Memory
1 Fuel Pump Relay Shorted/Open Relay Or Circuit To DME Control Unit Pin No. 1
2 Idle Speed Actuator (Close) (2) Shorted/Open Actuator Or Circuit To DME Control Unit Pin No. 2
3 Fuel Injector (No. 1) (3)(4) Shorted/Open Injector Or Circuit To DME Control Unit Pin No. 3
4 Fuel Injector (No. 3) (3)(4) Shorted/Open Injector Or Circuit To DME Control Unit Pin No. 4
5 Fuel Injector (No. 2) (3)(4) Shorted/Open Injector Or Circuit To DME Control Unit Pin No. 5
6 Fuel Injectors (Output Signal) (4) Shorted/Open Injector Or Circuit To DME Control Unit
8 CHECK ENGINE Light Shorted/Open Indicator Light Or Its Circuit Wiring
12 Throttle Potentiometer (TPS) Shorted/Open Circuit In Sensor Or Its Circuit Wiring
16 Camshaft (Pulse) Sensor (5) Camshaft (Pulse) Sensor Signal Interrupted Or Faulty
18 Output Stage (Signal) (1) Shorted Circuit To Ground/Battery Voltage At DME Control Unit Pin No. 18
19 Output Stage (Signal) (1) Shorted Circuit To Ground/Battery Voltage At DME Control Unit Pin No. 19
23 Ignition Coil (Cylinder No. 2) (1) Open Circuit In Ignition Output Signal For Cylinder No. 2 (Pin No. 23)
24 Ignition Coil (Cylinder No. 3) (1) Open Circuit In Ignition Output Signal For Cylinder No. 3 (Pin No. 24)
25 Ignition Coil (Cylinder No. 1) (1) Open Circuit In Ignition Output Signal For Cylinder No. 1 (Pin No. 25)
26 DME Power Supply (B+) Voltage Input Less Than Battery Voltage (Engine Off)
29 Idle Speed Actuator (Open) (2) Shorted Actuator/Circuit To DME Control Unit Pin No. 29, Output Signal Faulty
31 Fuel Injector (No. 5) (3)(4) Shorted/Open Injector Or Circuit To DME Control Unit Pin No. 31
32 Fuel Injector (No. 6) (3)(4) Shorted/Open Injector Or Circuit To DME Control Unit Pin No. 32
33 Fuel Injector (No. 4) (3)(4) Shorted/Open Injector Or Circuit To DME Control Unit Pin No. 33
34 Output Stage (Signal) (6) Shorted/Open Component Or Circuit To DME Control Unit
36 Fuel Tank Vent (Evaporation) Control Shorted/Open Fuel Evaporation Control Valve Or Circuit To DME Control Unit
37 Oxygen Sensor Heater Shorted/Open Oxygen Sensor/Heating Element Circuit To DME Control Unit
41 Air Mass (Sensor) Meter Shorted/Open Air Mass Sensor Or Its Circuit Wiring
46 Output Stage (Signal) (1) Shorted Circuit To Ground/Battery Voltage At Dme Control Unit Pin No. 46
48 A/C Compressor Shutoff (1)(7) A/C Compressor Not Switched Off At Speed Less Than 5 MPH
50 Ignition Coil (Cylinder No. 4) (1) Open Circuit In Ignition Output Signal For Cylinder No. 4 (Pin No. 50)
51 Ignition Coil (Cylinder No. 6) (1) Open Circuit In Ignition Output Signal For Cylinder No. 6 (Pin No. 51)
52 Ignition Coil (Cylinder No. 5) (1) Open Circuit In Ignition Output Signal For Cylinder No. 5 (Pin No. 52)
54 DME Power Supply Voltage To DME Control Unit Drops Below 10 Volts Or Exceeds 14 Volts
55 Ignition Output Stage (Signal) (1) Open Circuit, Defect Could Not Be Assigned To Any Specific Cylinder
64 Ignition Timing Intervention (8) Short To Ground In Circuit To DME Control Unit Pin No. 64
67 Crankshaft (Speed/ Position) Sensor (1) No Sensor Signal, Ignition And Fuel Injection Are Turned Off
70 Oxygen Sensor Shorted/Open Circuit On Oxygen Sensor Or Its Circuit Wiring
73 Vehicle Speed Sensor (9) Faulty Vehicle Speed Sensor Signal
77 Intake Air Temp. Sensor Shorted/Open Circuit In Sensor Or Its Circuit Wiring
78 Engine (Coolant) Temp. Sensor Shorted/Open Circuit On Sensor Or Its Circuit Wiring
81 Anti-Theft (DWA) Signal Anti-Theft System Is Detected As Being On After Engine Has Started
85 A/C Compressor A/C Compressor Is Detected As Being On And A/C Switch Signal Is Not Received
100 Output Stage (Signal) (1) Shorted Circuit To Ground/Battery Voltage At DME Control Unit Pin No. 100
200 DME Control Unit Code Is Set When An Internal Defect Is Found In RAM Or ROM/EPROM
201 Defect (Fault) Code Memory Code Is Set If Illogical Data Are Stored In Defect Code Memory
202 Emission Control Emission Controls Out Of Range, No Air/Fuel Mixture Related Problem Is Detected
(1) Fault codes applicable to 325 models only.
(2) Fault Code 29 is also stored when connection to idle actuator or power supply is interrupted. Fault Codes 2 and 29 are also stored when engine operation is interrupted without ignition being switched off. Defect is then detected at an engine speed less than 600 RPM.
(3) Fault Code 6 may also be stored as pin No. 6 is connected to all injectors.
(4) Fault Code 6 can be ignored if a code for a specific injector is stored.
(5) Simultaneous activation of ALL ignition coils takes place when camshaft sensor signal is interrupted.
(6) Components/circuits affected are: idle speed actuator, oxygen sensor heater relay, fuel evaporation control, fuel pump relay, CHECK ENGINE light. Fault Code 34 can be ignored if a code for a specific injector is stored.
(7) Fault described occurs when circuit is shorted to ground. When circuit is shorted to battery voltage, A/C compressor never operates (engages).
(8) Fault code is set when wiring from control unit pin No. 64 to electronic transmission control (EGS) unit has a short to ground for at least 2.5 seconds. Ignition timing is adjusted in retard direction only once, after which this signal is ignored.
(9) Code is set when engine speed is greater than 4500 RPM at high loads for a minimum of 10 seconds.
RENDER: 1.0x

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