Hard Failures
Hard failures cause CHECK ENGINE light to illuminate and remain on until malfunction is repaired. If light comes on and remains on (light may flash) during vehicle operation, cause of malfunction must be determined by using FAULT CODES table (if testing with voltmeter) or diagnostic CODE CHARTS (if testing with DRB-II). If a sensor fails, ECU will use a substitute value in its calculations to continue engine operation. In this condition, vehicle is functional, but loss of good driveability may result.
Intermittent Failures
Intermittent failures may cause CHECK ENGINE light to flicker or illuminate and go out after intermittent fault goes away. However, corresponding trouble code will be retained in ECU memory. If related fault does not reoccur within a certain time frame, related trouble code will be erased from ECU memory. Intermittent failures may be caused by a sensor, connector or wiring related problems. See INTERMITTENTS in TESTS W/O CODES article in the ENGINE PERFORMANCE Section.
RETRIEVING CODES (USING VOLTMETER)
- Before entering on-board diagnostics, see «PRETEST INSPECTION»(ref-10726-S26787357612000111000000). Turn ignition switch to OFF position. Locate self-diagnostic connector, which is next to fuse block. Using an analog voltmeter, connect volt-meter positive lead to self-diagnostic connector terminal No. 1 (output) and negative lead to terminal No. 12 (ground). (Scheme 14)
- Turn ignition switch to ON position and disclosure of ECU memory will begin. If 2 or more systems are non-functional, they are indicated by order of increasing code number. Indication is made by 12-volt pulses of voltmeter pointer. A constant repetition of short 12-volt pulses indicates system is normal. If system is abnormal, voltmeter will pulse between zero and 12 volts.
- Signals will appear on voltmeter as long and short 12-volt pulses. Long pulses represent tens; short pulses represent ones. For example, 4 long pulses and 3 short pulses indicate Code 43. After recording abnormal code(s), perform necessary repair. See «FAULT CODES»(ref-10726-S28270806222000111000000).
Scheme 14
YES Or Down Arrow & NO Or Up Arrow
Keys will move lines on screen up or down, allowing user to choose an item or scroll through all selections available.
F1 & F2 Keys
Keys are used to scroll through sensor displays.
ATM Key
Key will return user to previous screen.
ENTER Key
Allows user to select a test or display. Flashing arrow must be on display user wishes to select. Pressing ENTER in sensor state will cause display to change from a 3-line display to a 1-line display.
F3 Key
Key is used to display a help screen. This key may be used at any time.
Number Keys
Keys are used for choosing a display or test by number for test or display.
READ/HOLD Key
Key is used to freeze any sensor display.
MODE & ATM Keys
Pressing MODE and ATM keys at same time will cause DRB-II to reset to copyright screen.
RETRIEVING CODES (USING DRB-II)
- Before entering on-board diagnostics, see «PRE-TEST INSPECTION»(ref-10726-S26787357612000111000000) . Turn ignition off. Locate self-diagnostic connector, which is next to fuse block. Using appropriate Mitsubishi cartridge and adapter, connect DRB-II to diagnostic connector.
- Ensure all accessories are off. Turn ignition on. All character positions will illuminate and copyright information will appear on screen for a few seconds.
- If DRB-II screen displays an error message, see DRB-II ERROR SCREENS. DRB-II will offer 4 menus: VEHICLES TESTED, HOW TO USE, CONFIGURE and SELECT VEHICLE.
VEHICLES TESTED
Press "1" key or ENTER key when VEHICLES TESTED appears on DRB-II. DRB-II shows models covered by cartridge. Screen will display for 5 seconds and return to DRB-II menu. To return to DRB-II menu sooner, press ATM key.
HOW TO USE
Press "2" key or press down arrow to display HOW TO USE option and press ENTER. Press and hold F3 key. DRB-II displays instructions for cartridge usage. To return to DRB-II menu, press ATM key.
CONFIGURE
Press "3" key or press down arrow to display CONFIGURE option, and press ENTER. CONFIGURE allows user to customize DRB-II display. For example, if metric system is more useful, select METRIC from menu. All selections in CONFIGURE option remain active until user changes selection.
SELECT VEHICLE
- This allows user to enter information about vehicle being tested. Usually, this option has more than one display screen. Use ENTER key to enter vehicle information.
- When all information about vehicle is entered, DRB-II will display an information summary technician has entered. DRB-II will show an additional option marked CONFIRM. If information is correct, press CONFIRM. DRB-II will display MAIN MENU.
MAIN MENU represents all diagnostic functions available. Functions are SYSTEM TESTS, READ FAULTS, STATE DISPLAYS, ACTUATOR TESTS and ADJUSTMENTS. SYSTEM TESTS is NOT available.
READ FAULTS
This allows technician to read fault codes stored in ECU memory.
STATE DISPLAYS
- This allows technician to view conditions at signal level. The 2 types of signals are analog and digital. Analog signals are monitored at pins corresponding to vehicle harness splices (e.g., fuel pump relay).
- Digital signals correspond to data transmitted by system controllers. Both signals are displayed in common units (e.g., temperature). Use up and down arrow keys on DRB-II to scroll through displays available.
- Following ENGINE state displays are available on DRB-II: Module Information: This mode allows technician to read ECU part number and application. Engine Sensors: This mode allows technician to look at various engine sensors during engine operation. Inputs/Outputs: This mode allows technician to read input and output states of various switches and sensors. Custom Display: This screen allows technician to set up his/her own custom display. Two custom display screens can be programmed into DRB-II. Minimum/Current/Maximum: MIN/CURRENT/MAX display shows a history of conditions for a specific sensor. When this option is selected, maximum, current (static) and minimum values can be displayed for a specific sensor. To reset sensors to a zero value, simply press ENTER key. This display may be used to isolate intermittent faults. MIN/CURRENT/MAX display allows technician to observe operation of 6 different sensor values. Information is displayed as a 3-digit number. First value displayed is the minimum reading, second number is current reading and third value is the maximum reading. Typically sensors range between 2 and 252. Values less than 2 or greater than 252 will usually indicate that a sensor is shorted or disconnected. Watch minimum and maximum values to help diagnose intermittent problems. Monitors: This screen shows technician sensors and system controllers which affect fuel control, spark advance, RPM and A/C relay. There are 4 different screens available. For example, screen No. 1 will show: airflow sensor, O2 sensor, battery and fuel injector. All of these inputs affect fuel control.
Actuator Tests
This mode allows technician to actuate injectors, fuel pump, purge control, EGR solenoid, fuel pressure solenoid and wastegate.
SYSTEM FAULT ROM CHECK SUM XXXX Message
Cartridge or DRB-II failure.
SYSTEM FAULT KEYBOARD FAILURE Message
Restart DRB-II. Ensure DRB-II keys are not pressed during power up. Another possibility is DRB-II failure.
SYSTEM FAULT ROM FAILURE XXXX Message
DRB-II failure.
SYSTEM FAULT EEPROM FAILURE Message
DRB-II failure.
SYSTEM FAILURE, COMMUNICATION FAILURE, REFER TO
DIAGNOSTIC PROCEDURES Message
On 1.5L, 2.4L and 3.0L Ram-50, perform diagnostic connector test. See DRIVEABILITY TEST No. 8 (DR-8). Failure of Mitsubishi Motor Corporation (MMC) adapter is another possibility.
SYSTEM FAILURE NO RESPONSE FROM ADAPTER or SYSTEM FAILURE
ADAPTER REQUIRED TO DIAGNOSE WITH THIS CARTRIDGE Message
Ensure you are using a correct Mitsubishi Motor Corporation cartridge. Failure of MMC adapter is another possibility.
FAULT CODES
Note. Codes listed in FAULT CODES table are not used on all vehicles.
| Code | Component | (1) Possible Cause |
|---|---|---|
| (2) | Engine Control Unit | Engine Control Unit |
| 11 | Oxygen Sensor (3) | Harness & Connector, Oxygen Sensor, Fuel Pressure, Injectors, Intake Air Leaks |
| 12 | Airflow Sensor | Harness & Connector, Airflow Meter |
| 13 | Intake Air Temperature Sensor | Harness & Connector, Intake Air Temperature Sensor |
| 14 | Throttle Position Sensor | Harness & Connector, Throttle Position Sensor, Idle Position Switch |
| 15 | Motor Position Sensor | Harness & Connector, Motor Position Sensor, Throttle Position Sensor |
| 21 | Coolant Temperature Sensor | Harness & Connector, Coolant Temperature Sensor |
| 22 | Crank Angle Sensor | Harness & Connector, Distributor Assembly |
| 23 | Top Dead Center Sensor | Harness & Connector, Crank Angle Sensor |
| 24 | Vehicle Speed Sensor | Harness & Connector, Vehicle Speed Sensor |
| 25 | Barometric Pressure Sensor | Harness & Connector, Barometric Pressure Sensor |
| 31 | Detonation Sensor (4) | Harness & Connector, Detonation Sensor |
| 36 | Ignition Timing Adjustment Signal | Harness & Connector |
| 39 | Oxygen Sensor (5) | Harness & Connector, Oxygen Sensor, Fuel Pressure, Injectors, Air Intake Leaks |
| 41 | Injector | Harness & Connector, Injector Coil Resistance |
| 42 | Fuel Pump | Harness & Connector, Control Relay |
| 43 | EGR (6) | Harness & Connector, EGR Temperature Sensor, EGR Valve, EGR Control Solenoid, EGR Valve Control Vacuum |
| 44 | Ign. Coil & Power Transistor (Cyl. No. 1 & 4) (4) | Harness & Connector, Ignition Coil, Power Transistor |
| 52 | Ign. Coil & Power Transistor (Cyl. No. 2 & 5) (4) | Harness & Connector, Ignition Coil, Power Transistor |
| 53 | Ign. Coil & Power Transistor (Cyl. No. 3 & 6) (4) | Harness & Connector, Ignition Coil, Power Transistor |
| 61 | Torque Reduction Signal Low (4) (7) | Harness & Connector, Transaxle Control Unit |
| 62 | Induction Control Valve Position Sensor (8) | Harness & Connector, Induction Control Valve Position Sensor, Air Intake Plenum Assembly |
| (1) Replace ECU if inspection of possible cause items reveals no problem. (2) CHECK ENGINE Light Stays On (3) Applies to non-turbo models. (4) Dual Overhead Cam (DOHC) models. (5) Oxygen sensor for front cylinders on Stealth turbo. (6) California only. (7) Automatic transaxle only. (8) Non-turbo only. | ||
| (1) | Replace ECU if inspection of possible cause items reveals no problem. |
| (2) | CHECK ENGINE Light Stays On |
| (3) | Applies to non-turbo models. |
| (4) | Dual Overhead Cam (DOHC) models. |
| (5) | Oxygen sensor for front cylinders on Stealth turbo. |
| (6) | California only. |
| (7) | Automatic transaxle only. |
| (8) | Non-turbo only. |
FAULT CODES
CLEARING CODES
Using DRB-II, from main menu select ADJUSTMENTS. Enter ERASE FAULTS. Follow DRB-II instructions to accomplish this task. If DRB-II is not available, fault codes may be cleared by disconnecting negative battery cable for at least 10 seconds, allowing ECU to clear fault codes.
SUMMARY
If no hard fault codes (or only pass codes) are present, driveability symptoms exist or intermittent codes exist, proceed to TESTS W/O CODES article in the ENGINE PERFORMANCE Section for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.) or intermittent diagnostic procedures.