INTRODUCTION
If no faults were found while performing BASIC TESTING , proceed with self-diagnostics. If no fault codes or only pass codes are present after entering self-diagnostics, proceed to H -TESTS W/O CODES article for diagnosis by symptom (i.e. ROUGH IDLE, NO START, etc.).
DIAGNOSIS & TESTING
Use code charts listed in SELF-DIAGNOSTICS DIRECTORY table when using Chrysler's Diagnostic Readout Box (DRB-II). If DRB-II is not available, system diagnosis can be accomplished using a voltmeter or appropriate scan tester. See ENTERING ON-BOARD DIAGNOSTICS (USING VOLTMETER) .
| Application | Start at Test |
|---|---|
| 1.8L | NS-1A |
SELF-DIAGNOSTICS DIRECTORY
SYSTEM DIAGNOSIS
Note. Chrysler Motors recommends using DRB-II to diagnose system. Voltmeter usage has limited diagnostic capabilities but can be used if DRB-II is not available.
The Engine Control Unit (ECU) monitors several different engine control system circuits. If an abnormal input signal occurs, a fault code is stored in ECU memory and given a fault code number. Each circuit has its own fault number and message. A specific fault code results from a particular system failure. It is NOT necessarily the reason for that failure. The fault code does not condemn a specific component. The fault code calls out a probable malfunction area. If a critical fault code is set, the ECU will turn on CHECK ENGINE light. All fault codes except speed sensor are considered critical.
Fault codes can be confirmed by using a voltmeter, DRB-II, or appropriate scan tester. See ENTERING ON-BOARD DIAGNOSTICS (USING VOLTMETER) or ENTERING ON-BOARD DIAGNOSTICS (USING DRB-II) . By using DRB-II, the self-diagnostic capabilities of this system can simplify testing and reduce diagnostic time.
System malfunctions encountered are identified as either hard failures or intermittent failures as determined by the ECU.
HARD FAILURES
Hard failures cause CHECK ENGINE light to illuminate and remain on until the malfunction is repaired. If light comes on and remains on (light may flash) during vehicle operation, cause of malfunction must be determined by using appropriate DIAGNOSTIC FAULT CHART (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 FAULTS
Intermittent faults may cause CHECK ENGINE light to flicker or illuminate and go out after the intermittent fault goes away. However, the corresponding trouble code will be retained in ECU memory. If related fault does not reoccur within a certain time frame, related trouble will be erased from ECU memory. Intermittent failures may be caused by a sensor, connector, or wiring related problem. See INTERMITTENTS in G - TESTS W/O CODES - 1.8L article.
PRETEST INSPECTION
Before proceeding with diagnosis, the following precautions must be followed
- Always check if any TECHNICAL SERVICE BULLETINS apply to vehicle.
- Use caution whenever it is necessary to remove a fuel line or fitting. Fuel is under pressure and may result in personal injury.
- When using trouble shooting charts for diagnosis, DO NOT skip any steps in chart or incorrect diagnosis may result. Always perform VERIFICATION PROCEDURE test after repairs are made.
- When using a jumper wire, ensure either the jumper wire or circuit is fuse-protected.
- Vehicle must have a fully charged battery and functional charging system.
- Probe ECU connector from pin side. DO NOT backprobe ECU connector.
- DO NOT cause short circuits when performing electrical tests. This will set additional fault codes, making diagnosis of original problem more difficult.
- DO NOT use a test light in place of a voltmeter.
- When checking for spark, ensure coil wire is NOT more than 1/4" from ground. If coil wire is more than 1/4" from ground, damage to vehicle electronics and/or ECU may result.
- DO NOT prolong testing of fuel injectors or engine may hydrostatically (liquid) lock.
- When vehicle has multiple fault codes, always repair lowest number fault code first or first fault displayed (DRB-II) first.
- Always disconnect DRB-II after use.
- Always disconnect DRB-II before charging battery.
ENTERING ON-BOARD DIAGNOSTICS (USING VOLTMETER)
Note. Before proceeding with diagnosis, certain precautions must be followed. See PRETEST INSPECTION .
Scheme 25
Scheme 26
- Turn ignition off. Using an analog voltmeter, connect voltmeter positive lead to self-diagnostic connector terminal No. 1 and negative lead to terminal No. 12 (ground). Diagnostic connector is located next to junction block, above left kick panel. (Scheme 25)
- Ensure all accessories are off. 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, one long sweep followed by a short pause followed by 4 short sweeps would indicate a Code 14. (Scheme 26) After recording abnormal codes, perform necessary repair according to appropriate diagnostic fault chart. (Scheme 27)
- After repair, turn ignition off. Disconnect negative battery cable for 10 seconds to erase ECU memory. Reconnect negative battery cable and repeat self-diagnostics to confirm repair.
Scheme 27
DIAGNOSTIC PROCEDURE (USING DRB-II)
Note. Before proceeding with diagnosis, certain precautions must be followed. See PRETEST INSPECTION .
Refer to ENTERING ON-BOARD DIAGNOSTICS (USING DRB-II) to retrieve fault codes. If fault codes are not present and/or DRB-II is used, proceed to one of the following tests
- Go to «NO START TEST 1A (NS-1A)»(/plymouth/laser/i-1989-1994/remont/testing-diagnostics/#engine-controls-tests-wcodes-18l) chart if a no-start condition exists or engine stalls after start-up. After repairs, perform indicated VERIFICATION PROCEDURE test. Ensure code charts apply to engine being tested.
- Go to «DRIVEABILITY TEST 1A (DR-1A)»(/plymouth/laser/i-1989-1994/remont/testing-diagnostics/#engine-controls-tests-wcodes-18l) chart if engine runs but has performance problems. Perform indicated VERIFICATION PROCEDURE test after repairs. Ensure charts apply to engine being tested.
YES OR DOWN ARROW & NO OR UP ARROW
Keys will move lines on screen up or down, allowing technician 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 technician to previous screen.
ENTER Key
Allows technician to select a test or display. The flashing arrow must be on the display you wish to select. Pressing the ENTER key in the 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 the number for the test or display.
READ/HOLD KEY
Key is used to freeze any sensor display.
MODE & ATM KEY
Pressing MODE and ATM key at the same time will cause DRB-II to reset to copyright screen.
ENTERING ON-BOARD DIAGNOSTICS (USING DRB-II)
- Before entering on-board diagnostics, refer to «PRETEST INSPECTION»(/plymouth/laser/i-1989-1994/remont/testing-diagnostics/#engine-controls-tests-wcodes-18l__pretest-inspection). Turn ignition off. Attach Mitsubishi Motors Corporation (MMC) cartridge to DRB-II. Connect DRB-II to diagnostic connector. Diagnostic connector is located next to junction block, above left kick panel. (Scheme 25)
- Ensure all accessories are off. Turn ignition on. All character positions will illuminate and copyright information will appear on screen for a few seconds. Display will then change to DRB-II menu.
- If DRB-II displays an error message, refer to «DRB-II ERROR SCREENS»(/plymouth/laser/i-1989-1994/remont/testing-diagnostics/#engine-controls-tests-wcodes-18l). The following DRB-II modes can be accessed from DRB-II menu: VEHICLES TESTED, HOW TO USE, CONFIGURE and SELECT SYSTEM.
VEHICLES TESTED MODE
Press "1" or ENTER key when VEHICLES TESTED appears on DRB-II display. DRB-II shows vehicles supported by cartridge used. This 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 MODE
Press "2" key or press downward facing arrow button to display HOW TO USE option. Press ENTER key. DRB-II will display instructions for use of DRB-II with cartridge being used.
CONFIGURE MODE
Press "3" key or ENTER key when CONFIGURE appears on DRB-II display. Configure option allows technician to customize DRB-II display. For example, if metric system is more useful to use, simply select METRIC from the appropriate menu. All selections made under the CONFIGURE option remain active until user changes selection.
SELECT SYSTEM MODE
- This option enables the technician to enter information about vehicle being tested. Usually this option will have more than one display screen. Use ENTER key to enter vehicle information.
- When all information about the vehicle is entered, DRB-II will display a summary of information technician entered as a confirming menu. DRB-II will show an additional option marked CONFIRM. If information is correct, press YES key. DRB-II will display ENGINE MENU.
The ENGINE MENU will present all diagnostic modes available for vehicle selected. The following ENGINE MENU modes can be accessed: SYSTEM TESTS, READ FAULTS, STATE DISPLAYS, ACTUATOR TESTS and ADJUSTMENTS. SYSTEM TESTS is not available for engine diagnostics program.
READ FAULTS MODE
This mode allows technician to read fault codes stored in ECU memory.
STATE DISPLAYS MODE
- This display enables technician to view conditions at the signal level. The 2 types of signals used 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 the system controllers. Both signals are displayed in common units (e.g. temperature), but this information is not relative to diagnostic intent. Use up and down arrow keys on DRB-II to scroll through displays available.
- The following state displays are available on the DRB-II
MODULE INFORMATION
Allows technician to read ECU part number and application.
ENGINE SENSORS
Allows technician to look at various engine sensors and system controllers during engine operation.
INPUTS/OUTPUTS
Allows technician to read input and output states of various switches and sensors that affect ECU operation.
MONITORS
This screen shows technician sensors and system controllers that affect fuel control, spark advance, RPM and A/C relay. There are 4 different screens available. An example screen No. 1 will show: AIRFLOW SENSOR, O2 SENSOR, BATTERY, FUEL INJECTOR, THROTTLE POSITION SENSOR (TPS), BAROMETRIC PRESSURE SENSOR, COOLANT SENSOR and RPM. All of these inputs affect fuel control.
CUSTOM DISPLAY
This screen allows technician to set up their own custom display. Two custom display screens can be programmed into DRB-II.
ACTUATOR TESTS
This mode on DRB-II allows technician to actuate injectors, fuel pump, purge control, fuel pressure solenoid and wastegate.
Most of the tests available in this mode provide an audible or visual indication of device operation (click of relay contacts, spray fuel, etc.). With the exception of an intermittent condition, if a device functions properly during its test, it can be assumed that the device, wiring and its driver circuit are functioning properly.
ADJUSTMENTS
This option provides a means for erasing fault code information stored in ECU. Follow DRB-II instructions to accomplish this task.
Scheme 28
- To access volt/ohmmeter mode of DRB-II, connect Red volt/ohmmeter test lead to Red port, located on right top side of DRB-II. NOTE: Because DRB-II is grounded through engine diagnostic connector, only one volt/ohmmeter test lead is required when using volt/ohmmeter option. DRB-II volt/ohmmeter should only be used when diagnostic flow charts require the use of this option.
- To access voltmeter, press VOLT/OHM key once. DRB-II is now in voltmeter mode. Touch test probe to connector or wire to be measured. Read voltage on DRB-II display. When voltage testing is complete, press VOLT/OHM key 3 times to exit voltmeter mode.
- To access ohmmeter, press VOLT/OHM key twice. DRB-II is now in ohmmeter mode. Touch test probe to connector or wire to be measured. Read resistance to circuit ground on DRB-II display. When resistance testing is complete, press VOLT/OHM key twice to exit ohmmeter mode.
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. DRB-II failure is possible.
SYSTEM FAULT RAM FAILURE XXXX MESSAGE
DRB-II failure.
SYSTEM FAULT EPROM FAILURE MESSAGE
DRB-II failure.
SYSTEM FAILURE, COMMUNICATION FAILURE, REFER TO DIAGNOSTIC PROCEDURES MESSAGE
Perform pretest inspection. See PRETEST INSPECTION . MMC cartridge failure is possible.
SYSTEM FAILURE NO RESPONSE FROM ADAPTER Or SYSTEM FAILURE ADAPTER REQUIRED TO DIAGNOSE WITH THIS CARTRIDGE MESSAGE
Ensure you are using a MMC cartridge for a Mitsubishi vehicle. Repair or replace adapter and/or DRB-II.
FAULT CODES
| Fault Code | System Fault Description |
|---|---|
| 0 (1) | Normal Condition |
| 11 | Open Or Short In O2 Sensor Circuit |
| 12 | Open Or Short In Airflow Sensor Circuit |
| 13 | Open Or Short In Intake Air Temperature Sensor Circuit |
| 14 | Open Or Short In TPS Circuit |
| 15 | Open Or Short In Motor Position Sensor Circuit |
| 21 | Open Or Short In Coolant Temperature Sensor Circuit |
| 22 | No Voltage Change In Crank Angle Sensor Signal |
| 23 | No Voltage Change In No. 1 Cylinder TDC Sensor Signal |
| 24 | No Voltage Change Of Vehicle Speed Sensor (VSS) Signal |
| 25 | Open Or Short In Barometric Pressure Sensor |
| 41 | Open Or Short In Injection Circuit |
| 42 | Open Or Short In Fuel Pump Drive Circuit |
| 43 | Open Or Short In EGR Temperature Sensor Circuit |
| Steady CHECK ENGINE light (2) | Faulty ECU |
| (1) When the CHECK ENGINE light flashes on and off continuously without pausing, this will be read as a zero indicating a normal condition. (2) When CHECK ENGINE light illuminates steadily without flashing, this indicates a faulty ECU. | |
| (1) | When the CHECK ENGINE light flashes on and off continuously without pausing, this will be read as a zero indicating a normal condition. |
| (2) | When CHECK ENGINE light illuminates steadily without flashing, this indicates a faulty ECU. |
FAULT CODES
CLEARING CODES
Using DRB-II, enter ADJUSTMENTS screen and follow instructions. See ENTERING ON-BOARD DIAGNOSTICS (USING DRB-II) . If DRB-II is not available, disconnect 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 for diagnosis by symptom (i.e. ROUGH IDLE, NO START, etc.) or intermittent diagnostic procedures.
CODE CHARTS
Note. The following code charts and illustrations are courtesy of Chrysler Motors. To locate appropriate code chart for vehicle being worked on, see SELF-DIAGNOSTICS DIRECTORY table.
No Start Test NS-1A: Diagnostic Flow Chart (1 of 3). Scheme 29
No Start Test NS-1A: Diagnostic Flow Chart (2 of 3). Scheme 30
No Start Test NS-1A: Diagnostic Flow Chart (3 of 3). Scheme 31
No Start Test NS-2A: Diagnostic Flow Chart (1 of 2). Scheme 32
No Start Test NS-2A: Diagnostic Flow Chart (2 of 2). Scheme 33
No Start Test NS-3A: Diagnostic Flow Chart. Scheme 34
No Start Test NS-4A: Diagnostic Flow Chart (1 of 2). Scheme 35
No Start Test NS-4A: Diagnostic Flow Chart (2 of 2). Scheme 36
No Start Test NS-5A: Circuit Diagram. Scheme 37
No Start Test NS-5A: Diagnostic Flow Chart. Scheme 38
No Start Test NS-6A: Circuit Diagram. Scheme 39
No Start Test NS-6A: Diagnostic Flow Chart (1 of 2). Scheme 40
No Start Test NS-6A: Diagnostic Flow Chart (2 of 2). Scheme 41
VER-1 Verification Procedure 1: Diagnostic Flow Chart. Scheme 42
Driveability Test DR-1A: Diagnostic Flow Chart (1 of 2). Scheme 43
Driveability Test DR-1A: Diagnostic Flow Chart (2 of 2). Scheme 44
Driveability Test DR-2A: Circuit Diagram. Scheme 45
Driveability Test DR-2A: Diagnostic Flow Chart. Scheme 46
Driveability Test DR-3A: Circuit Diagram. Scheme 47
Driveability Test DR-3A: Diagnostic Flow Chart (1 of 2). Scheme 48
Driveability Test DR-3A: Diagnostic Flow Chart (2 of 2). Scheme 49
Driveability Test DR-4A: Diagnostic Flow Chart (1 of 2). Scheme 50
Driveability Test DR-4A: Diagnostic Flow Chart (2 of 2). Scheme 51
Driveability Test DR-5A: Circuit Diagram. Scheme 52
Driveability Test DR-5A: Diagnostic Flow Chart (1 of 2). Scheme 53
Driveability Test DR-5A: Diagnostic Flow Chart (2 of 2). Scheme 54
Driveability Test DR-6A: Circuit Diagram. Scheme 55
Driveability Test DR-6A: Diagnostic Flow Chart (1 of 2). Scheme 56
Driveability Test DR-6A: Diagnostic Flow Chart (2 of 2). Scheme 57
Driveability Test DR-7A: Circuit Diagram. Scheme 58
Driveability Test DR-7A: Diagnostic Flow Chart (1 of 2). Scheme 59
Driveability Test DR-7A: Diagnostic Flow Chart (2 of 2). Scheme 60
Driveability Test DR-8A: Circuit Diagram. Scheme 61
Driveability Test DR-8A: Diagnostic Flow Chart. Scheme 62
Driveability Test DR-9A: Circuit Diagram. Scheme 63
Driveability Test DR-9A: Diagnostic Flow Chart. Scheme 64
Driveability Test DR-10A: Diagnostic Flow Chart (1 of 2). Scheme 65
Driveability Test DR-10A: Diagnostic Flow Chart (2 of 2). Scheme 66
Driveability Test DR-11A: Circuit Diagram. Scheme 67
Driveability Test DR-11A: Diagnostic Flow Chart (1 of 5). Scheme 68
Driveability Test DR-11A: Diagnostic Flow Chart (2 of 5). Scheme 69
Driveability Test DR-11A: Diagnostic Flow Chart (3 of 5). Scheme 70
Driveability Test DR-11A: Diagnostic Flow Chart (4 of 5). Scheme 71
Driveability Test DR-11A: Diagnostic Flow Chart (5 of 5). Scheme 72
Driveability Test DR-12A: Circuit Diagram. Scheme 73
Driveability Test DR-12A: Diagnostic Flow Chart. Scheme 74
Driveability Test DR-13A: Circuit Diagram. Scheme 75
Driveability Test DR-13A: Diagnostic Flow Chart (1 of 2). Scheme 76
Driveability Test DR-13A: Diagnostic Flow Chart (2 of 2). Scheme 77
Driveability Test DR-14A: Diagnostic Flow Chart (1 of 4). Scheme 78
Driveability Test DR-14A: Diagnostic Flow Chart (2 of 4). Scheme 79
Driveability Test DR-14A: Diagnostic Flow Chart (3 of 4). Scheme 80
Driveability Test DR-14A: Diagnostic Flow Chart (4 of 4). Scheme 81
Driveability Test DR-15A: Diagnostic Flow Chart (1 of 3). Scheme 82
Driveability Test DR-15A: Diagnostic Flow Chart (2 of 3). Scheme 83
Driveability Test DR-15A: Diagnostic Flow Chart (3 of 3). Scheme 84
Driveability Test DR-16A: Circuit Diagram. Scheme 85
Driveability Test DR-16A: Diagnostic Flow Chart (1 of 3). Scheme 86
Driveability Test DR-16A: Diagnostic Flow Chart (2 of 3). Scheme 87
Driveability Test DR-16A: Diagnostic Flow Chart (3 of 3). Scheme 88
Driveability Test DR-17A: Diagnostic Flow Chart. Scheme 89
Driveability Test DR-18A: Circuit Diagram. Scheme 90
Driveability Test DR-18A: Diagnostic Flow Chart. Scheme 91
Driveability Test DR-19A: Diagnostic Flow Chart. Scheme 92
DR-20A: INSPECTION OF MECHANICAL SYSTEM & COMPONENTS
The systems controlled by the Electronic Control Unit (ECU) are functioning as intended. This indicates that a mechanical system malfunction is the cause of the driveability problem. Check if any TECHNICAL SERVICE BULLETINS relate to this driveability problem. The following areas should also be examined
- Check ignition timing.
- Check engine vacuum.
- Check engine compression.
- Check valve timing.
- Check for exhaust system restriction.
- Check torque converter stall speed.
- Check for fuel contamination.
- Check secondary ignition circuit for abnormal scope pattern.
