Alfa Romeo fault codes

Alfa Romeo cars are mainly equipped with Bosch control systems, including: Bosch Motronic ML4.1, 1.7, 2.10.3 / 4, MP3 versions. 1, as well as Multec XM and Weber IAF 8F 6B. All Alfa systems control the primary circuit of the ignition system, the fuel injectors and the idling system from one unit.

 

Engine control systems have a self-diagnostic function that continuously analyzes the signals of the sensors and actuators of the engine and compares them with the reference values. If the diagnostic program detects a mismatch, one or more corresponding fault codes are recorded in the memory of the electronic control unit (BLU). Codes will not appear in cases where the defective item is not under the control of the ACM and when a bad situation is not provided for by its software.

Bosch Motronic ML4.1 and 1.7

In these systems, the electronic control unit generates 4-digit "flashing" codes for manual reading. When extracting these codes with the reader, the numbers displayed on its display can be completely different. Further codes are given, which are obtained both with the help of a flashing light bulb, and with the help of a reader. When diagnosing, use the appropriate column of the table, depending on the method of reading.

Other systems

The Alfa-Romeo software does not generate digital trouble codes for systems other than Bosch Motronic ML4.1 and 1.7. The reader reproduces the fault on the screen without accessing the codes. Although the digital code is not available, a malfunction of the system program, if it appears, will be fixed and stored in memory.

 

The Alfa-Romeo system has a mode of limited controllability (a function known as "limp home" or "crash home"). This means that if some malfunctions occur (not all malfunctions cause this mode to be activated), the engine control system is guided not by the sensor reading, but by its reference value. This mode allows the car to reach the garage or service station for inspection and repair, albeit with less efficiency. After troubleshooting, the system returns to normal operation.

 

All Alfa-Romeo systems have the ability to adapt, in which the programmed parameter values for some sensors and actuators change during operation, taking into account engine wear for maximum control efficiency.

Models for the USA, in accordance with national requirements, are equipped with a warning light bulb "Check Engine" ("Check engine") located in the instrument panel. With the same bulb, it is also possible to extract trouble codes that can lead to a deterioration in the exhaust composition. Models for the European market are not equipped with such an alarm system.

Bosch Motronic ML4.1

Two diagnostic connectors are located in the passenger compartment under the dashboard. The 3-pin connector is for connecting the code reader (see Figure 5.1), and the 4-pin connector for reading the "flashing" codes.

Bosch Motronic M 1.7

To read the code in any way intended 3-pin connector located generally under the dashboard on the passenger side next to the ECU.

Other systems

The 3-pin connector is only for connecting the reader. It can be located in the engine compartment on the right wing or in the center console next to the ECU or under the dashboard on the driver's side or the passenger side next to the ECU.

  1. Connect the LED and auxiliary switch to the 4-pin connector.
  2. Switch on the ignition - the LED should light.
  3. Close the auxiliary switch for 2.5 ... 5.0 seconds, then open it. The LED will light for another 2.5 seconds, then it will start flashing.
  4. Read the 4-digit codes reproduced by the LED as follows.
  5. Four numbers are indicated by four series of flashes.
  6. The first series of flashes means the first digit of the second series - the second digit, etc. up to the fourth.
  7. Each series consists of several flashes lasting 1 or 8 seconds with short gaps between them. The numbers from 1 to 9 are indicated by 1-second flashes, and zero is indicated by a two-second flare.
  8. One series from the other is separated by a pause of 2.5 seconds.
  9. Code 1213 is reproduced as follows: one 1-second flash, a short pause, two 1-second flashes, a short pause, one 1-second flash, a short pause, three 1-second flashes. After 2.5 seconds, the code will be repeated.
  10. Count the number of flashes in the series and write down the code. To decode its value, refer to the table at the end of the chapter.
  11. Each code will be repeated until you again close the auxiliary switch for 2.5 ... 5.0 seconds, and then open it. After that, the following code will blink. The ML4.1 system can simultaneously store in memory no more than 5 codes.
  12. Continue to extract the codes until code 0000 appears, which means that there are no more codes in the ECU memory.
  13. If code 4444 appears at once, it means that no fault codes have been registered.
  14. At the end of the reading procedure, turn off the ignition and disconnect the LED and switch.

Bosch Motronic 1.7

  1. Ensure that the throttle potentiometer is operational. The procedure described below can not be performed if the ECU does not receive the correct signal from this sensor.
  2. Connect the LED between the (+) power supply and pin # 8 of the ECU connector. It will be necessary to detach the rear of the ECU connector to get to the correct pin without disconnecting the connector. Be careful - do not damage the connector's pins and do not short-circuit the two LEDs with the dipstick.
  3. Switch on the ignition, but do not start the engine. Five times in a row, fully press and release the accelerator pedal. This process should be completed within 5 seconds after the ignition is turned on.
  4. The LED will light for 2.5 seconds, then it will start flashing.
  5. Read the 4-digit codes reproduced by the LED as follows:
  6. Four numbers are indicated by four series of flashes.
  7. The first series of flashes means the first digit, the second series - the second digit, etc. up to the fourth.
  8. Each series consists of several flashes lasting 1 or 8 seconds with short gaps between them. The numbers from 1 to 9 are denoted by 1-secund flashes, and zero is indicated by a two-second flash.
  9. One series from the other is separated by a pause of 2.5 seconds.
  10. Code 1313 is reproduced as follows: one 1-second flash, a short pause, two 1-second flashes, a short pause, one 1-second flash, a short pause, three 1-second flashes. After 8.5 seconds, the code will be repeated.
  11. Count the number of flashes in the series and write down the code.
  12. Each code will be repeated until you press and release the accelerator pedal 5 times for 5 seconds. After that, the following code will blink.
  13. Continue to extract the codes until code 0000 or 1000 appears, which means that there are no more codes in the ECU memory.
  14. If code 4444 appears at once, it means that no fault codes have been registered.
  15. At the end of the reading procedure, turn off the ignition and disconnect the LED and switch.

In other ECU systems - "flashing" codes are not provided. It is necessary to use the code reader.

Deleting codes from memory without the help of a reader

Bosch Motronic ML4.1

  1. To extract the codes, use the procedure described above.
  2. When code 0000 appears, short-circuit the auxiliary switch for about 10 seconds, then open it. All codes in memory will be erased.
  3. Turn off the ignition and remove the auxiliary switch.

Bosch Motronic M 1.7

  1. To extract the codes, use the procedure described above.
  2. When code 0000 or 1000 appears, fully depress the accelerator pedal for about 10 seconds, then release it. All codes in memory will be erased.
  3. Turn the ignition off.

All systems (alternative method)

  1. Turn the ignition off and disconnect the negative lead from the battery terminal for about 5 minutes.
  2. Reconnect the wire to the battery. The first drawback of this method is that the ECU will reset all the adapted parameter values to its original state. In order to re-adjust the system to your engine, it will be necessary to start the engine from the cold state, and then ride the car at different engine speeds 20 ... 30 minutes. In addition, it is necessary to let the engine idle for about 10 minutes.

Checking actuators without the aid of a reader

Only Bosch Motronic ML4.1

  1. Connect the LED and the auxiliary switch.
  2. Close the auxiliary switch and turn on the ignition.
  3. Wait 2.5 ... 5.0 seconds and open the switch. The LED will show the code 1411 and simultaneously the fuel injection system will be activated. The work of the solenoids of the injectors will be clearly audible.
  4. The nozzles will work as long as the auxiliary switch is open. There is a danger to pour the cylinders with gasoline. Therefore, if you need long (more than 1 second) tests, turn off the power to the fuel pump or remove the fuse.
  5. Stop the injector check by closing the auxiliary switch.
  6. After 2.5 ... 5.0 seconds, open the switch again. The LED will show the code 1412 and simultaneously activate the idle valve. The solenoid valve will be heard.
  7. Stop the valve check by closing the auxiliary switch.
  8. After 2.5 ... 5.0 seconds, open the switch again. The LED will show the code 1413 and the valve timing solenoid will be activated. His work will be clearly audible.
  9. Stop the solenoid check by closing the auxiliary switch.
  10. After 2.5 ... 5.0 seconds, open the light switch again - the light diode will show the code 1414 and the charcoal filter purge valve will start working. His work will be clearly audible.
  11. Stop the charcoal filter check by closing the auxiliary switch.
  12. After 2.5 ... 5.0 seconds, open the switch. The LED will show the code 0000, which completes the check of the actuators.
  13. Turn the ignition off and remove the LED with the switch.

To check the actuators of other systems, a code reader is needed.

Alfa Romeo Deciphering fault codes

Bosch Motronic ML4.1 and 1.7

"Flashing" code

Reader

Malfunction

00000000

Horses passing codes

1000

End of transmission codes

1211

037

Battery

1212

052

Limit sensor throttle
(idle)

1213

053

Limit sensor throttle
(full load)

1214

045

Sensor or the temperature sensor circuit
coolant

1215

043

With the regulator or his chain

1216

012

Potentiometer throttle
or his chain

1221

007

Air flow sensor or with damper
his chain

1222

004

The idling speed control valve or
his chain

1223

010

Oxygen sensor or its circuit

1224

028

Oxygen sensor or its circuit

1225

044

Air temperature sensor or
his chain

1226

100

Electronic control unit (LPG)

1227

Nozzles or their chain

1228

Nozzles or their chain

1229

Heater control system
conditioning

1231

031

Speedometer signal is automatic
transmission

1232

032

Injector (1 and 3 for 4-cylinder
engine or 1, 2 and 4 to 6-shlindrovogo engine)

1233

002

Nozzles (2 and 4 for 4-cylinder
motor or 3, 5 and 6 to 6-cipindrovogo engine)

1234

013

Automatic transmission or
control circuit

1235

085

A/c or
her chain

1236

021

Activation of the compressor of air conditioner

1243

1003

The fuel pump relay or his chain

1244

034

Purge valve carbon filter
or his chain

1245

023

The Executive mechanism of automatic
variable valve timing or his chain

1251

001

Electronic control unit (LPG)

1252

009

Crank angle sensor
shaft or chain it

1254

Potentiometer throttle
or his chain

1255

Camshaft position sensor
shaft or chain it

1265

015

Diagnostic indicator lamp
system or chain

2111

Knock sensor 1 circuit or its

2112

Knock sensor 2 circuit or its

2113

Electronic control unit (LPG)

2116

Electronic control unit (LPG)

444

LPG contains no fault codes

 

All systems except Bosch Motronic ML4.1 and 1.7

The Alfa-Romeo software does not generate digital trouble codes for systems other than Bosch Motronic ML4.1 and 1.7. The code reader reproduces the fault on the screen without accessing the codes. Although the digital code is not available, a malfunction of the system program, if it appears, will be fixed and stored in memory.