Troubleshooting (Mitsubishi Lancer 9)

Reading diagnostic trouble codes

1. Turn the ignition switch to the "OFF" position.

2. When checking with a tester:

• a) Connect the tester to the diagnostic connector under the instrument panel.

Caution: When connecting or disconnecting the tester, the ignition must be turned off (ignition key in the "OFF" position).

• b) Turn on the ignition.

3. Read and write down the fault codes.

4. After completing the check, turn the ignition switch to the "OFF" position and then disconnect the tester from the diagnostic connector.

Checking the SRS system

1. Check the operation of the SRS indicator on the instrument cluster:

• a) Make sure that the indicator lights up when the ignition is turned on.
• b) Make sure that after turning on the ignition, the indicator goes out after approximately 7 seconds.
• c) If the indicator does not go out, read the fault codes.

2. Read the SRS diagnostic trouble codes using a tester, then erase the diagnostic trouble codes from the SRS control unit memory.

3. Check for the symptom. Start the engine and stop it after a few seconds, then read the SRS diagnostic trouble codes again.

a) If there are no fault codes, then the fault was temporary (occurring intermittently).

b) If a trouble code is present, check the SRS system in accordance with the subsection "Diagnostic codes and probable causes of malfunctions".

Diagnostic codes and probable causes of malfunctions

Caution: Each air bag module igniter circuit connector has a safety mechanism built into it that prevents the positive wire from being accidentally shorted to ground when the connector is disconnected (e.g. due to static electricity). Therefore, if the connector is damaged or connected incorrectly, the safety mechanism may remain in the locked state when the connector is connected.

Note:

• - Diagnostic codes marked with "*¹" are automatically erased from memory when the system returns to normal. In this case, the SRS indicator returns to normal operation.
• - Diagnostic codes marked with "*²", when the faults that caused them are eliminated, remain in the control unit's memory (the fault history is saved), but the SRS indicator in this case also switches to normal operation mode.
• - If the vehicle's battery is discharged, fault codes #41 or #42 will be stored in the memory. Check the battery if these fault codes appear.

Code #14: Analog acceleration sensor and its circuits

Note: This DTC is displayed when a sensor (located inside the SRS control unit) malfunctions, the sensor characteristics are abnormal, or the sensor output signal is abnormal.

Probable cause of the malfunction:

SRS electronic control unit malfunction.

Codes #15 and #16: Front Airbag Crash Sensor and Its Circuits

Note: These codes are output when the resistance value between the sensor terminals inside the SRS control unit is not within the standard value range.

Possible reasons for the appearance of codes:

1. Fault code No.15:

• Short circuit in the safety shock sensor.

2. Fault code No.16:

• Open circuit in the safety shock sensor.

Probable cause of the malfunction:

SRS electronic control unit malfunction.

Codes #21*¹, №22*¹, #61 and #62: Driver Frontal Airbag Module Circuits (Igniter)

Note: These trouble codes appear when the resistance value between the terminals of the air bag module (igniter) inside the SRS control unit is not within the specified range.

Possible reasons for the appearance of codes:

1. Fault code No.21:

• Short circuit in the driver's front airbag ignition circuit.
• Short circuit in the spiral wire.
• Defective connector safety mechanism, incorrectly connected or damaged wiring harness connector.

2. Fault code No.22:

• Open circuit in the front airbag ignition circuit.
• Open circuit of the spiral wire.
• Poor connection or breakage due to incorrect neutral position of the spiral wire.
• The connector of the driver's front airbag module (igniter) is disconnected.
• No contact in the wiring harness connector.

13. Fault code No.61:

• Short circuit to power supply in driver's front airbag ignition wiring.
• Spiral wire defect.
• Damage to wiring or wiring harness connector.

14. Fault code No.62:

• Short circuit to ground in the driver's front airbag ignition wiring.
• Spiral wire defect.
• Damage to wiring or wiring harness connector.

Probable cause of the malfunction:

• 1. Malfunction of the spiral wire or its incorrect installation (incorrect neutral position).
• 2. Incorrect connection, defective or damaged connectors. Malfunction in the wiring harness or in the connectors of the wiring harness.
• 3. Malfunction of the driver's front airbag module (electric igniter).
• 4. Malfunction of the SRS electronic control unit.

Codes #24*¹, №25*¹, #64 and #65: Front passenger airbag module circuits (igniter)

Note: These trouble codes appear when the resistance value between the terminals of the front passenger air bag module (igniter) inside the SRS control unit is not within the specified range.

Possible reasons for the appearance of codes:

1. Fault code No.24:

• Short circuit in the front passenger airbag igniter circuit or in the wiring harness.
• The connector safety mechanism is defective, the connector is damaged or not connected correctly.

2. Fault code No.25:

• Open circuit in the front passenger airbag ignition circuit or open circuit in the wiring harness.
• Lack of contact in the wiring harness connector.

3. Fault code No.64:

• Short circuit to power source in front passenger airbag ignition wiring.
• Damage to wiring or wiring harness connector.

4. Fault code No.65:

• Short circuit to ground in the wiring of the electric igniter of the front passenger airbag.
• Damage to wiring or wiring harness connector.

Probable cause of the malfunction:

• 1. Incorrect connection, defective or damaged connectors. Malfunction in the wiring harness or in the connectors of the wiring harness.
• 2. Malfunction of the passenger front airbag module (electric igniter).
• 3. Malfunction of the SRS electronic control unit.

Codes #26*¹, №27*¹, #66 and #67: Driver's seat belt pretensioner circuit (electric igniter)

Note: These trouble codes are displayed when the resistance value between the terminals of the driver seat belt pretensioner module (igniter) inside the SRS control unit is not within the specified range.

Possible reasons for the appearance of codes:

1. Fault code No.26:

• Short circuit in the driver's seat belt pretensioner ignition circuit.
• The connector safety mechanism is defective, the connector is damaged or not connected correctly.

2. Fault code No.27:

• Open circuit in the driver's seat belt pretensioner ignition circuit.
• Lack of contact in the wiring harness connector.

3. Fault code No.66:

• Short circuit to power supply in driver's seat belt pretensioner ignition wiring.
• Damage to wiring or wiring harness connector.

4. Fault code No.67:

• Short circuit to ground in the driver's seat belt pretensioner ignition wiring.
• Damage to wiring or wiring harness connector.

Probable cause of the malfunction:

• 1. Malfunction in the wiring harness or in the wiring harness connectors.
• 2. Malfunction of the driver's seat belt pretensioner module (electric igniter).
• 3. Malfunction of the SRS electronic control unit.

Codes #28*¹, №29*¹, #68 and #69: Passenger seat belt pretensioner circuit (electric igniter)

Note: These DTCs are displayed when the resistance value between the terminals of the passenger seat belt pretensioner module (igniter) inside the SRS control unit is not within the specified range.

Possible reasons for the appearance of codes:

1. Fault code No.28:

• Short circuit in the passenger seat belt pretensioner ignition circuit.
• The connector safety mechanism is defective, the connector is damaged or not connected correctly.

2. Fault code No.29:

• Open circuit in the electric ignition circuit of the passenger seat belt pretensioner.
• Lack of contact in the wiring harness connector.

3. Fault code No.68:

• Short circuit to power supply in passenger seat belt pretensioner ignition wiring.
• Damage to wiring or wiring harness connector.

4. Fault code No.69:

• Short circuit to ground in the passenger seat belt pretensioner ignition wiring.
• Damage to wiring or wiring harness connector.

Probable cause of the malfunction:

• 1. Malfunction in the wiring harness or in the wiring harness connectors.
• 2. Malfunction of the passenger seat belt pretensioner module (electric igniter).
• 3. Malfunction of the SRS electronic control unit.

Codes #31 and #32: Electronic control unit capacitor and its circuit

Note: These codes are output when the voltage at the capacitor terminals remains above (code #31) or below (code #32) the specified value for 5 seconds or longer.

Probable cause of the malfunction:

SRS electronic control unit malfunction.

Note: Code #32 will not appear if codes #41 and #42 are present, indicating a drop in battery voltage.

Code #34²: SRS Electronic Control Unit Electrical Connector Lock Check Circuit

Note: This fault code is generated when there is a poor connection in the SRS electronic control unit connector.

Probable cause of the malfunction:

• 1. Malfunction (poor contact) in the SRS control unit connector or open circuit in the wiring harness.
• 2. Malfunction of the SRS electronic control unit.

Code #35: SRS Electronic Control Unit (if airbag deployed)

Note: This fault code is output after the driver's airbag (code #35) or passenger's airbag (code #46) has deployed. If the airbags have not deployed and this code is present, the cause of the fault is inside the SRS electronic control unit.

Probable cause of the malfunction:

SRS electronic control unit malfunction.

Code #41²: Ignition switch power supply circuit IG1 (A).

Note: This trouble code is output if the voltage between the IG1 (A) terminal (corresponding terminal of the SRS control unit connector) and ground remains less than the specified value (9 V) for 5 seconds or more. However, if the voltage returns to the normal value, trouble code No.41 will be automatically cleared from memory and the SRS indicator will go out.

Probable cause of the malfunction:

• 1. Malfunction (poor contact) in the wiring harness connector or open circuit in the wiring harness.
• 2. Malfunction of the SRS electronic control unit.

Code #42²: Ignition switch power supply circuit IG1 (B).

Note: This trouble code is output if the voltage between the IG-i terminal (B) (corresponding terminal of the SRS control unit connector) and ground remains less than the specified value (9 V) for 5 seconds or more. However, if the voltage returns to the normal value, trouble code No.42 will be automatically cleared from the memory and the SRS indicator will go out.

Probable cause of the malfunction:

• 1. Malfunction (poor contact) in the connector, wiring harness, or open circuit in the wiring harness.
• 2. Malfunction of the SRS electronic control unit.

Note: If codes #41 and #42 are displayed simultaneously, you must first check the condition of the battery.

Code #43²: SRS indicator control circuit (Indicator does not light)

Note: The SRS ECU controls the operation of the SRS indicator and outputs this trouble code if an open circuit is detected for 5 seconds and the indicator is not illuminated.

Probable cause of the malfunction:

• 1. Malfunction (poor contact) in the wiring harness connector or open circuit in the wiring harness.
• 2. The lamp burned out.
• 3. Malfunction of the SRS electronic control unit.
• 4. Instrument cluster malfunction.

Code #43²: SRS indicator control circuit (Lamp does not turn off)

Note: This trouble code is output when there is a short to ground in the wire between the SRS indicator and the SRS control module.

Probable cause of the malfunction:

• 1. Malfunction (poor contact) in the wiring harness connector or open circuit in the wiring harness.
• 2. Malfunction of the SRS electronic control unit.
• 3. Instrument cluster malfunction.

Code #44²: SRS indicator control circuit

Note: This trouble code is output if there is a short circuit in the SRS indicator control circuit or if the control transistor inside the SRS control unit has failed.

Probable cause of the malfunction:

• 1. Malfunction of the SRS electronic control unit.
• 2. Malfunction in the wiring harness connector.

Code #45: EEPROM circuits inside the SRS electronic control unit

Note: This code is displayed when the non-erasable memory (electrically programmable read-only memory) is faulty (EEPROM)) inside the SRS electronic control unit.

Probable cause of the malfunction:

SRS electronic control unit malfunction.

Codes #51 or #52: Driver Frontal Air Bag Module Circuit (Igniter Control Circuit)

Note: This code is set if there is a short circuit (#51) or an open circuit (#52) in the driver frontal air bag module igniter control circuit.

Probable cause of the malfunction:

SRS electronic control unit malfunction.

Codes #54 or #55: Passenger Frontal Air Bag Module Circuit (Igniter Control Circuit)

Note: This code is output if there is a short circuit (#54) or an open circuit (#55) in the passenger front airbag module igniter control circuit.

Probable cause of the malfunction:

SRS electronic control unit malfunction.

Codes #56 or #57: Driver Seat Belt Pretensioner Circuit (Igniter Control Circuit)

Note: This code is output if a short circuit (No. 56) or open circuit (No. 57) occurs in the driver's seat belt pretensioner control circuit.

Probable cause of the malfunction:

SRS electronic control unit malfunction.

Codes #58 or #59: Passenger Seat Belt Pretensioner Circuit (Igniter Control Circuit)

Note: This code is output if a short circuit (#56) or open circuit (#57) occurs in the passenger seat belt pretensioner control circuit.

Probable cause of the malfunction:

SRS electronic control unit malfunction.

Signs of malfunctions without fault codes

In the following cases, the probable cause of the malfunction is either a malfunction (poor contact) in the connector or an open circuit in the wiring harness, or a malfunction of the SRS electronic control unit.

1. If it is not possible to output fault codes (communication with the tester is impossible) for all electronic systems of the vehicle, then there is probably no power supply in the diagnostic circuit (there may also be no contact with the "ground").

2. If it is not possible to output fault codes (communication with the tester is impossible) only for the SRS system, then there is probably an open circuit in the output signal circuit of the SRS diagnostic line, or an open circuit in the power supply circuit (there may also be no contact with the "ground").

3. If the SRS indicator does not turn off, there is probably a short circuit in the wiring between the SRS indicator and the SRS control unit.

Signs of malfunctions without fault codes

In the following cases, the probable cause of the malfunction is either a malfunction (poor contact) in the connector or an open circuit in the wiring harness, or a malfunction of the SRS electronic control unit.

1. If it is not possible to output fault codes (communication with the tester is impossible) for all electronic systems of the vehicle, then there is probably no power supply in the diagnostic circuit (there may also be no contact with the "ground").

2. If it is not possible to output fault codes (communication with the tester is impossible) only for the SRS system, then there is probably an open circuit in the output signal circuit of the SRS diagnostic line, or an open circuit in the power supply circuit (there may also be no contact with the "ground").

3. If the SRS indicator does not turn off, there is probably a short circuit in the wiring between the SRS indicator and the SRS control unit.

The text of the article was obtained from the website: www.mitsubishiman.ru