Dodge Ram 50 Sport 1991 - 1991 ENGINE PERFORMANCE Self-Diagnostics - 2.4L

Dodge Ram 50 Sport 1991 - 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 TESTS W/O CODES article in this section for diagnosis by symptom (i.e. ROUGH IDLE, NO START, etc.).

Dodge Ram 50 Sport 1991 - SELF-DIAGNOSTIC SYSTEM INTRODUCTION

Use Chrysler Motors code charts when using Chrysler's Diagnostic Readout Box (DRB-II). See DRB-II CODE CHARTS. If DRB-II is not available system diagnosis can only be accomplished using a voltmeter or appropriate scan tester. To diagnose using a voltmeter, see ENTERING ON-BOARD DIAGNOSTICS (USING VOLTMETER) in this article.

Dodge Ram 50 Sport 1991 - 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.

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 indicates a particular system failure, but it DOES NOT indicate that cause of failure is necessarily within system. A fault code DOES NOT condemn any specific component; it simply points out a probable malfunctioning area. If a critical fault code is set, 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 or Chrysler's Diagnostic Readout Box (DRB-II). See ENTERING ON-BOARD DIAGNOSTICS (USING VOLTMETER) or ENTERING ON-BOARD DIAGNOSTICS (USING DRB-II) in this article. By using DRB-II, 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 ECU.

Dodge Ram 50 Sport 1991 - 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 DIAGNOSTIC FAULT CHARTS (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.

Dodge Ram 50 Sport 1991 - 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 problems. See INTERMITTENTS in TESTS W/O CODES article in the ENGINE PERFORMANCE Section.

Dodge Ram 50 Sport 1991 - PRETEST INSPECTION

Before proceeding with diagnosis, following precautions must be observed:

• Vehicle must have a fully charged battery and functional charging system.
• Visually inspect connectors and circuit wiring being worked on.
• DO NOT disconnect battery or ECU. This will erase any fault codes stored in ECU.
• 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. Engine may hydrostatically (liquid) lock.
• When a vehicle has multiple fault codes, always repair lowest number fault code first.
• If using DRB-II to diagnose system, always perform verification test after repairs are made.

Dodge Ram 50 Sport 1991 - ENTERING ON-BOARD DIAGNOSTICS (USING VOLTMETER)

1. Before entering on-board diagnostics, refer to PRETEST INSPECTION. Turn ignition switch to OFF position. Locate self-diagnostic connector. See SELF-DIAGNOSTIC TEST CONNECTOR LOCATION table. Using an analog voltmeter, connect voltmeter positive lead to self-diagnostic connector terminal No. 1 and negative lead to terminal No. 12 (ground). See Fig. 4 .
2. 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.
3. 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 indicates Code 43. See Fig. 1 -Fig. 3 . After recording abnormal code(s), perform necessary repair. See DIAGNOSTIC FAULT CHART .
4. After repair, turn ignition off and disconnect negative battery cable for 10 seconds to erase ECU memory. Reconnect power supply and repeat self-diagnostics to confirm repair.

Dodge Ram 50 Sport 1991 SELF-DIAGNOSTIC TEST CONNECTOR LOCATION

Application	Location
Ram-50	Next to fuse block

Dodge Ram 50 Sport 1991 - DIAGNOSTIC FAULT CHARTS

NOTE:

Replace ECU if a malfunction code exists and inspection reveals no problem with check items.

Fig. 1: Dodge Ram 50 Sport 1991 - Component Locations - Diagnostic Fault Chart (1 of 3)

Fig. 2: Dodge Ram 50 Sport 1991 - Component Locations - Diagnostic Fault Chart (2 of 3)

Fig. 3: Dodge Ram 50 Sport 1991 - Component Locations - Diagnostic Fault Chart (3 of 3)

Dodge Ram 50 Sport 1991 - DIAGNOSTIC PROCEDURE (USING DRB-II)

NOTE:

When using diagnostic code charts, DO NOT skip any steps in chart or incorrect diagnosis may result. Always check related Technical Service Bulletins (TSBs).

- ENTERING ON-BOARD DIAGNOSTICS (USING DRB-II) to retrieve fault codes. If fault codes are NOT present and DRB-II is used, proceed to one of following tests:

• Go to NO START TEST 1 (NS-1) chart if a no-start condition exists or engine stalls after start-up. Perform indicated VERIFICATION PROCEDURE chart after repairs. Ensure charts apply to engine being tested.
• Go to DRIVEABILITY TEST 1 (DR-1) chart if engine runs but has performance problems. Perform indicated VERIFICATION PROCEDURE chart (when provided) after repairs. Ensure charts apply to engine being tested.

Dodge Ram 50 Sport 1991 - DRB-II KEY FUNCTIONS

• 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.

Dodge Ram 50 Sport 1991 - ENTERING ON-BOARD DIAGNOSTICS (USING DRB-II)

1. Before entering on-board diagnostics, see PRETEST INSPECTION . Turn ignition off. Locate self-diagnostic connector. See SELF-DIAGNOSTIC TEST CONNECTOR LOCATION table. Using appropriate Mitsubishi cartridge and adapter, connect DRB-II to diagnostic connector.
2. Ensure all accessories are off. Turn ignition on. All character positions will illuminate and copyright information will appear on screen for a few seconds.
3. If DRB-II screen displays an error message, refer to DRB-II ERROR SCREENS . DRB-II will offer 4 menus: VEHICLES TESTED, HOW TO USE, CONFIGURE and SELECT VEHICLE.

Dodge Ram 50 Sport 1991 - 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.

Dodge Ram 50 Sport 1991 - 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.

Dodge Ram 50 Sport 1991 - 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.

Dodge Ram 50 Sport 1991 - Select Vehicle

1. 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.
2. 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.

Dodge Ram 50 Sport 1991 - 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.

Dodge Ram 50 Sport 1991 - Read Faults

This allows technician to read fault codes stored in ECU memory.

Dodge Ram 50 Sport 1991 - State Displays

1. 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).
2. 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.
3. 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 the 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.
   • Adjustments: This option provides a means for erasing fault code information stored in ECU. Follow DRB-II instructions to accomplish this task.

Dodge Ram 50 Sport 1991 - DRB-II ERROR SCREENS System Fault ROM Check Sum $XXXX Message

Cartridge or DRB-II failure.

Dodge Ram 50 Sport 1991 - System Fault Keyboard Failure Message

Restart DRB-II. Ensure DRB-II keys are not pressed during power up. Another possibility is DRB-II failure.

Dodge Ram 50 Sport 1991 - System Fault ROM Failure $XXXX Message

DRB-II failure.

Dodge Ram 50 Sport 1991 - System Fault EEPROM Failure Message

DRB-II failure.

Dodge Ram 50 Sport 1991 - System Failure, Communication Failure, Refer To Diagnostic

Procedures Message

Perform diagnostic connector test. See DRIVEABILITY TEST No. 8 (DR-8). Failure of Mitsubishi Motor Corporation (MMC) adapter is another possibility.

Dodge Ram 50 Sport 1991 - 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.

Fig. 4: Dodge Ram 50 Sport 1991 - Component Locations - Identifying Self-Diagnostic Connector Terminals

Fig. 5: Dodge Ram 50 Sport 1991 - Component Locations - 10 WAY ECU Connector Terminal ID

Fig. 6: Dodge Ram 50 Sport 1991 - Component Locations - 18 WAY ECU Connector Terminal ID

Fig. 7: Dodge Ram 50 Sport 1991 - Component Locations - 24 WAY ECU Connector Terminal ID

Dodge Ram 50 Sport 1991 - FAULT CODES

Dodge Ram 50 Sport 1991 FAULT CODE

Fault Code	System Fault Description
11	Open or short in O2 sensor ckt.
12	Open or short in airflow sensor ckt.
13	Open or short in intake air temp. sensor ckt.
14	Open or short in TPS ckt.
15	Open or short in motor position sensor ckt.
21	Open or short in coolant temp. sensor ckt.
22	No voltage change in crank angle sensor signal
23	No voltage change in TDC sensor ckt.
24 (1)	No voltage change in vehicle speed sensor signal
25	Open or short in barometric pressure sensor
31	Open or short in detonation sensor ckt.
36	Open or short in ignition timing ckt.
39	Open or short in front O2 sensor ckt. O2 Sensor Fuel pressure Faulty injectors (Replace if defective) Intake air leaks
41	Open or short in injector ckt.
42	Open or short in fuel pump drive ckt.
43 (2)	Open or short in EGR temp. sensor ckt.
44	Open or short in either ign. coil ckt.
52	Open or short in 2-5 ignition coil ckt.
53	Open or short in 3-6 ignition coil ckt.
61	Open or short in transaxle control unit or cable
62	Open or short in harness or connector of induction control valve position sensor. If harness, connector and induction control valve are normal, replace air intake plenum assembly.
(1) Will not turn on CHECK ENGINE light. (2) California only.

Dodge Ram 50 Sport 1991 - 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.

Dodge Ram 50 Sport 1991 - SUMMARY

If no hard fault codes (or only pass codes) are present, 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.

Dodge Ram 50 Sport 1991 - CODE CHARTS * PLEASE READ THIS FIRST *

NOTE:

Following trouble shooting charts and illustrations are courtesy of Chrysler Motors. To identify ECU and self- diagnostic connector terminals, see Fig. 4 - Fig. 7 .

Dodge Ram 50 Sport 1991 - NS-1: TESTING IGNITION CIRCUIT

Fig. 8: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-1 Test Schematic (1 of 6) Testing Ignition Circuit

Fig. 9: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-1 Test Flow Chart (1 of 6) Testing Ignition Circuit

Fig. 10: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-1 Test Schematic (2 of 6) Testing Ignition Circuit

Fig. 11: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-1 Test Flow Chart (2 of 6) Testing Ignition Circuit

Fig. 12: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-1 Test Schematic (3 of 6) Testing Ignition Circuit

Fig. 13: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-1 Test Flow Chart (3 of 6) Testing Ignition Circuit

Fig. 14: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-1 Test Schematic (4 of 6) Testing Ignition Circuit

Fig. 15: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-1 Test Flow Chart (4 of 6) Testing Ignition Circuit

Fig. 16: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-1 Test Flow Chart (5 of 6) Testing Ignition Circuit

Fig. 17: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-1 Test Schematic (6 of 6) Testing Ignition Circuit

Fig. 18: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-1 Test Flow Chart (6 of 6) Testing Ignition Circuit

Dodge Ram 50 Sport 1991 - NS-2: TESTING FOR FUEL

Fig. 19: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-2 Test Schematic (1 of 3) Testing For Fuel Check

Fig. 20: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-2 Test Flow Chart (1 of 3) Testing For Fuel Check

Fig. 21: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-2 Test Schematic (2 of 3) Testing For Fuel Check

Fig. 22: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-2 Test Flow Chart (2 of 3) Testing For Fuel Check

Fig. 23: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-2 Test Schematic (3 of 3) Testing For Fuel Check

Fig. 24: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-2 Test Flow Chart (3 of 3) Testing For Fuel Check

Dodge Ram 50 Sport 1991 - NS-3: TESTING FUEL PUMP CIRCUIT

Fig. 25: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-3 Test Schematic Testing Fuel Pump Circuit

Fig. 26: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-3 Test Flow Chart (1 of 2) Testing Fuel Pump Circuit

Fig. 27: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-3 Test Flow Chart (2 of 2) Testing Fuel Pump Circuit

Dodge Ram 50 Sport 1991 - NS-4: CHECKING CONTROL RELAY CIRCUIT

Fig. 28: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-4 Test Schematic Checking Control Relay Circuit

Fig. 29: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-4 Test Flow Chart Checking Control Relay Circuit

Dodge Ram 50 Sport 1991 - NS-5: TESTING SELF-DIAGNOSTIC CONNECTOR

Fig. 30: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-5 Test Schematic Testing Self Diagnostic Connector

Fig. 31: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-5 Test Flow Chart Testing Self Diagnostic Connector

Dodge Ram 50 Sport 1991 - NS-VER: NO START VERIFICATION TEST

Fig. 32: Dodge Ram 50 Sport 1991 - Component Locations - Test NS-VER Test Flow Chart No Start Verification Test

Dodge Ram 50 Sport 1991 - DR-1: TESTING FOR FAULT CODES

Fig. 33: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-1 Test Schematic Testing For Fault Codes

Fig. 34: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-1 Test Flow Chart (1 of 2) Testing For Fault Codes

Fig. 35: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-1 Test Flow Chart (2 of 2) Testing For Fault Codes

Dodge Ram 50 Sport 1991 - DR-2: FAULT CODE TESTS

Fig. 36: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-2 Test Flow Chart (1 of 2) Fault Code Tests

Fig. 37: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-2 Test Flow Chart (2 of 2) Fault Code Tests

Dodge Ram 50 Sport 1991 - DR-3: OXYGEN SENSOR CIRCUIT(CODE 11)

Fig. 38: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-3 Code 11 Schematic Oxygen Sensor Circuit

Fig. 39: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-3 Code 11 Flow Chart (1 of 2) Oxygen Sensor Circuit

Fig. 40: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-3 Code 11 Flow Chart (2 of 2) Oxygen Sensor Circuit

Dodge Ram 50 Sport 1991 - DR-4: AIRFLOW SENSOR CIRCUIT(CODE 12)

Fig. 41: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-4 Code 12 Schematic (1 of 3) Airflow Sensor Circuit

Fig. 42: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-4 Code 12 Flow Chart (1 of 3) Airflow Sensor Circuit

Fig. 43: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-4 Code 12 Schematic (2 of 3) Airflow Sensor Circuit

Fig. 44: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-4 Code 12 Flow Chart (2 of 3) Airflow Sensor Circuit

Fig. 45: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-4 Code 12 Schematic (3 of 3) Airflow Sensor Circuit

Fig. 46: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-4 Code 12 Flow Chart (3 of 3) Airflow Sensor Circuit

Dodge Ram 50 Sport 1991 - DR-5: INTAKE AIR TEMPERATURE SENSOR(CODE 13)

Fig. 47: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-5 Code 13 Schematic Intake Air Temperature Sensor

Fig. 48: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-5 Code 13 Flow Chart (1 of 2) Intake Air Temperature Sensor

Fig. 49: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-5 Code 13 Flow Chart (2 of 2) Intake Air Temperature Sensor

Dodge Ram 50 Sport 1991 - DR-6: THROTTLE POSITION SENSOR CIRCUIT(CODE 14)

Fig. 50: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-6 Code 14 Schematic Throttle Position Sensor Circuit

Fig. 51: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-6 Code 14 Flow Chart (1 of 3) Throttle Position Sensor Circuit

Fig. 52: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-6 Code 14 Flow Chart (2 of 3) Throttle Position Sensor Circuit

Fig. 53: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-6 Code 14 Flow Chart (3 of 3) Throttle Position Sensor Circuit

Dodge Ram 50 Sport 1991 - DR-7: MOTOR POSITION SENSOR(CODE 15)

Fig. 54: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-7 Code 15 Schematic Motor Position Sensor

Fig. 55: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-7 Code 15 Flow Chart (1 of 3) Motor Position Sensor

Fig. 56: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-7 Code 15 Flow Chart (2 of 3) Motor Position Sensor

Fig. 57: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-7 Code 15 Flow Chart (3 of 3) Motor Position Sensor

Dodge Ram 50 Sport 1991 - DR-8: COOLANT TEMPERATURE SENSOR(CODE 21)

Fig. 58: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-8 Code 21 Schematic (1 of 2) Coolant Temperature Sensor

Fig. 59: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-8 Code 21 Flow Chart (1 of 2) Coolant Temperature Sensor

Fig. 60: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-8 Code 21 Schematic (2 of 2) Coolant Temperature Sensor

Fig. 61: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-8 Code 21 Flow Chart (2 of 2) Coolant Temperature Sensor

Dodge Ram 50 Sport 1991 - DR-9: CRANK ANGLE SENSOR CIRCUIT(CODE 22)

Fig. 62: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-9 Code 22 Schematic Crank Angle Sensor Circuit

Fig. 63: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-9 Code 22 Flow Chart Crank Angle Sensor Circuit

Dodge Ram 50 Sport 1991 - DR-10: TOP DEAD CENTER SENSOR(CODE 23)

Fig. 64: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-10 Code 23 Schematic Top Dead Center Sensor

Fig. 65: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-10 Code 23 Flow Chart (1 of 2) Top Dead Center Sensor

Fig. 66: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-10 Code 23 Flow Chart (2 of 2) Top Dead Center Sensor

Dodge Ram 50 Sport 1991 - DR-11: VEHICLE SPEED SENSOR CIRCUIT(CODE 24)

Fig. 67: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-11 Code 24 Schematic Vehicle Speed Sensor Circuit

Fig. 68: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-11 Code 24 Flow Chart (1 of 2) Vehicle Speed Sensor Circuit

Fig. 69: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-11 Code 24 Flow Chart (2 of 2) Vehicle Speed Sensor Circuit

Dodge Ram 50 Sport 1991 - DR-12: BAROMETRIC PRESSURE SENSOR CIRCUIT(CODE 25)

Fig. 70: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-12 Code 25 Schematic Barometric Pressure Sensor Circuit

Fig. 71: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-12 Code 25 Flow Chart (1 of 2) Barometric Pressure Sensor Circuit

Fig. 72: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-12 Code 25 Flow Chart (2 of 2) Barometric Pressure Sensor Circuit

Dodge Ram 50 Sport 1991 - DR-13: INJECTOR CIRCUIT(CODE 41)

Fig. 73: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-13 Code 41 Schematic Injector Circuit

Fig. 74: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-13 Code 41 Flow Chart (1 of 5) Injector Circuit

Fig. 75: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-13 Code 41 Flow Chart (2 of 5) Injector Circuit

Fig. 76: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-13 Code 41 Flow Chart (3 of 5) Injector Circuit

Fig. 77: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-13 Code 41 Flow Chart (4 of 5) Injector Circuit

Fig. 78: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-13 Code 41 Flow Chart (5 of 5) Injector Circuit

Dodge Ram 50 Sport 1991 - DR-14: FUEL PUMP CONTROL CIRCUIT(CODE 42)

Fig. 79: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-14 Code 42 Schematic Fuel Pump Control Circuit

Fig. 80: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-14 Code 42 Flow Chart (1 of 2) Fuel Pump Control Circuit

Fig. 81: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-14 Code 42 Flow Chart (2 of 2) Fuel Pump Control Circuit

Dodge Ram 50 Sport 1991 - DR-15: EGR TEMPERATURE SENSOR(CODE 43)

Fig. 82: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-15 Code 43 Schematic EGR Temperature Sensor

Fig. 83: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-15 Code 43 Flow Chart (1 of 2) EGR Temperature Sensor

Fig. 84: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-15 Code 43 Flow Chart (2 of 2) EGR Temperature Sensor

Dodge Ram 50 Sport 1991 - DR-16: NO FAULT CODE TESTS

Fig. 85: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-16 Schematic (1 of 2) No Fault Codes

Fig. 86: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-16 Flow Chart (1 of 3) No Fault Codes

Fig. 87: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-16 Schematic (2 of 2) No Fault Codes

Fig. 88: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-16 Flow Chart (2 of 3) No Fault Codes

Fig. 89: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-16 Flow Chart (3 of 3) No Fault Codes

Dodge Ram 50 Sport 1991 - DR-17: NO FAULT CODE SENSOR TESTS

Fig. 90: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-17 Schematic - Oxygen Sensor No Fault Code Sensor Tests

Fig. 91: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-17 Flow Chart (1 of 6) No Fault Code Sensor Tests

Fig. 92: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-17 Schematic - TPS Sensor No Fault Code Sensor Tests

Fig. 93: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-17 Flow Chart (2 of 6) No Fault Code Sensor Tests

Fig. 94: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-17 Schematic - Coolant Temp. Sensor No Fault Code Sensor Tests

Fig. 95: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-17 Flow Chart (3 of 6) No Fault Code Sensor Tests

Fig. 96: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-17 Schematic - BARO Sensor No Fault Code Sensor Tests

Fig. 97: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-17 Flow Chart (4 of 6) No Fault Code Sensor Tests

Fig. 98: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-17 Flow Chart (5 of 6) No Fault Code Sensor Tests

Fig. 99: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-17 Flow Chart (6 of 6) No Fault Code Sensor Tests

Dodge Ram 50 Sport 1991 - DR-18: NO FAULT CODE FUEL SYSTEM CALIBRATION TEST

Fig. 100: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-18 Flow Chart No Fault Code Fuel System Calibration Test

Dodge Ram 50 Sport 1991 - DR-19: NO FAULT CODE EGR CONTROL TEST

Fig. 101: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-19 Flow Chart No Fault Code EGR Control Test

Dodge Ram 50 Sport 1991 - DR-20: NO FAULT CODE PURGE CONTROL TEST

Fig. 102: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-20 Flow Chart No Fault Code Purge Control Test

Dodge Ram 50 Sport 1991 - DR-21: NO FAULT CODE MECHANICAL TEST

At this point in the driveability test procedure, you have determined that all of the engine control systems are operating as they were designed to. Therefore, they are not the cause of the driveability problem.

The following additional items can not be overlooked as possible causes of a driveability problem.

1. ENGINE VACUUM - Must be at least 13 inches in neutral.
2. ENGINE VALVE TIMING - To specifications.
3. ENGINE COMPRESSION - To specifications.
4. ENGINE EXHAUST SYSTEM - Must be free of any restrictions.
5. ENGINE P.C.V. SYSTEM - Must flow freely.
6. ENGINE DRIVE SPROCKETS - Cam and crank shaft.
7. TORQUE CONVERTER STALL SPEED - To specifications.
8. POWER BRAKE BOOSTER - No internal vacuum leaks.
9. FUEL CONTAMINATION - High alcohol or water content.
10. FUEL INJECTORS - Rough idle may be caused by injector control wire not connected to correct injector.
11. TECHNICAL SERVICE BULLETINS - Any that may apply to vehicle.
12. ENGINE SECONDARY IGNITION CHECK - Any abnormal scope pattern.

Any one or more of these items can give a driveability related problem. They can not be overlooked as possible causes.

Dodge Ram 50 Sport 1991 - DR-22: IGNITION ADJUST TERMINAL

Fig. 103: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-22 Schematic Ignition Adjust Terminal

Fig. 104: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-22 Flow Chart Ignition Adjust Terminal

Dodge Ram 50 Sport 1991 - DR-VER: Test DRIVEABILITY VERIFICATION TEST

Fig. 105: Dodge Ram 50 Sport 1991 - Component Locations - Test DR-VER Flow Chart Verification Test