Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1990 Mitsubishi SigmaFACTORY OEM SERVICE PROCEDURE
Engine Controls - Tests W/Codes
- Introduction
- Diagnosis & Testing
- System Diagnosis
- Notes
- Hard Failures
- Intermittent Failures
- Pretest Inspection
- Entering On-Board Diagnostics (Using Voltmeter)
- Diagnostic Procedure (Using DRB-II)
- Entering On-Board Diagnostics (Using DRB-II)
- DRB-II Error Screens
- SYSTEM FAULT ROM CHECK SUM XXXX Message
- SYSTEM FAULT KEYBOARD FAILURE Message
- System Fault ROM Failure XXXX
- System Fault EEPROM Failure
- System Failure, Communication Failure, Refer To Diagnostic Procedures Message
- SYSTEM FAILURE NO RESPONSE FROM ADAPTER or SYSTEM FAILURE ADAPTER REQUIRED TO DIAGNOSE WITH THIS CARTRIDGE MESSAGE
- Fault Codes
- Clearing Codes
- Summary
- Code Charts - 2.4L
- NS-1: Testing Ignition Circuit
- NS-2: Testing For Fuel
- NS-3: Testing Fuel Pump Circuit
- NS-4: Checking Control Relay Circuit
- NS-5: Testing Self-Diagnostic Connector
- Dr-1: Testing For Fault Codes
- Dr-2: Fault Code Tests
- Dr-3: Code 11 Oxygen Sensor Circuit
- Dr-4: Code 12 Airflow Sensor Circuit
- Dr-5: Code 13 Intake Air Temperature Sensor Circuit
- Dr-6: Code 14 Throttle Position Sensor Circuit
- Dr-7: Code 15 Motor Position Sensor Circuit
- Dr-8: Code 21 Coolant Temperature Sensor Circuit
- Dr-9: Code 22 Crank Angle Sensor Circuit
- Dr-10: Code 23 Top Dead Center Sensor Circuit
- Dr-11: Code 24 Vehicle Speed Sensor Circuit
- Dr-12: Code 25 Barometric Pressure Sensor Circuit
- Dr-13: Code 41 Injector Circuit
- Dr-14: Code 42 Fuel Pump Control Circuit
- Dr-15: Code 43 EGR Temperature Sensor Circuit
- Dr-16: No Fault Code Tests
- Dr-17: No Fault Code Sensor Tests
- Dr-18: No Fault Code Fuel System Calibration Test
- Dr-19: No Fault Code EGR Control Test
- Dr-20: No Fault Code Purge Control Test
- Dr-21: No Fault Code Mechanical Test
- NS-VER: Verification Test
- Dr-VER: Verification Test
- Code Charts - 3.0L
- NS-1: Testing Ignition Circuit
- NS-2: Checking For Fuel
- NS-3: Testing Fuel Pump Circuit
- NS-4: Testing Self-Diagnostic Connector
- NS-5: Testing Crank Angle Sensor Circuit
- NS-6: Testing Control Relay Circuit
- Dr-1: Testing For Fault Codes
- Dr-2: Code 11 Oxygen Sensor Circuit
- Dr-3: Code 12 Airflow Sensor Circuit
- Dr-4: Code 13 Air Temperature Sensor Circuit
- Dr-5: Code 14 Throttle Position Sensor Circuit
- Dr-7: Code 21 Coolant Temperature Sensor Circuit
- Dr-8: Testing Self-Diagnostic Connector
- Dr-9: Code 23 Top Dead Center Sensor Circuit
- Dr-10: Code 24 Vehicle Speed Sensor Circuit
- Dr-11: Code 25 Barometric Pressure Sensor Circuit
- Dr-12: Code 41 Fuel Injector Circuit
- Dr-14: Code 43 EGR Temperature Sensor Circuit
- Dr-15: No Fault Code Switch Tests
- Dr-16: No Fault Code Sensor Tests
- Dr-17: No Fault Code Purge Solenoid Test
- Dr-18: No Fault Code Mechanical Test
Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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