TESTING & DIAGNOSIS
Note. The Part Throttle Unlock (PTU) solenoid and lock-up torque converter solenoid are the same solenoid. This solenoid will be referred to as a PTU solenoid in this article.
SYSTEM DIAGNOSIS
The self-diagnostic capabilities of this system, if properly utilized, can greatly simplify testing. The SMEC has been programmed to monitor several different circuits of the engine control system. If a problem is sensed with a monitored circuit, a fault code is stored in the SMEC.
The check engine light will illuminate and SMEC will enter limp-in mode. In this mode, SMEC attempts to compensate for the failure of a particular component by substituting information from other sources. This will allow vehicle to be operated until proper repairs can be made.
Once these codes are known, refer to FAULT CODES listed in this article to determine the questionable circuit. Test circuits and repair or replace as necessary. If problem is repaired or ceases to exist, the logic module cancels fault codes after 50-100 ignition on/off cycles. If DRB-II is being used, refer to CLEARING CODES in this article.
The setting of a specific fault code is the result of a particular system failure, NOT the reason for that failure, such as failure of a specific component. The existence of a particular code denotes the probable area of the malfunction, not necessarily the failed component itself.
PRELIMINARY CHECKS
Most driveability problems in the engine control system result from faulty wiring or leaking hose connections. To avoid unnecessary component testing, a visual check should be performed before beginning trouble shooting procedures to help spot these common faults. A preliminary visual check should include
- Air ducts to air cleaner and from air cleaner to throttle body.
- Electrical connections at all components. Clean, tight and unbroken. Check vacuum lines for secure, leak-free connections in these areas
- Canister purge hose (this hose has a tee connector in it.)
- EGR vacuum line on EGR valve and EGR solenoid. Check hose between backpressure valve and exhaust supply tube on EGR.
- Evaporative control system.
- Fuel pressure regulator vacuum hose.
- MAP sensor.
- PCV valve hose and correct PCV valve.
- Power brake, speed control, heater and A/C system vacuum hoses.
- Throttle body. Ensure the following electrical connectors are securely attached
- 14-pin and 60-pin connectors at Single Module Engine Controller (SMEC).
- A/C clutch relay connector.
- AIS motor connector.
- ASD relay connector.
- Canister purge solenoid connector.
- Charge temperature sensor connector.
- Check engine light.
- Coolant temperature sensor connector.
- Distance (speed) sensor connector.
- Distributor connector.
- EGR diagnostic solenoid connector (California only).
- Fuel injector connector.
- Heated O2 sensor connector.
- MAP sensor connector.
- Radiator fan relay connector.
- TPS connector.
DIAGNOSTIC PROCEDURES
Refer to ENTERING ON-BOARD DIAGNOSTICS to retrieve fault codes. When using check engine light to retrieve fault codes, refer to description of DRB-II display under FAULT CODES for an explanation of fault code. Once description of fault code is obtained, refer to appropriate trouble shooting chart to diagnose problem. Use trouble shooting chart titles to find appropriate chart.
If no fault codes are present, but vehicle still displays one of the following conditions, go to appropriate test.
- No start condition. Go to NS-1.
- Cold driveability problem. Go to DR-1.
- Warm driveability problem. Go to DR-1.
- Check engine light is illuminated. Go to DR-1.
- Charging system problem. Go to CH-1.
- Speed control system problem. Go to SP-1.
Note. When using trouble shooting charts for diagnosis, DO NOT skip any steps in chart, as incorrect diagnosis will result.
Before proceeding with diagnosis, the following precautions must be followed
- Vehicle must have a fully charged battery.
- When performing a cold driveability test, engine must not have been started for at least 7 hours.
- When performing a warm driveability test, engine must be at normal operating temperature.
- When probing SMEC connectors, probe connectors from pin side. DO NOT backprobe connectors.
- When performing electrical tests, be careful to not cause any short circuits. This will set more 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 no more than 1/4" from ground. If wire is farther away from ground, damage to SMEC may result.
- DO NOT prolong testing of fuel injectors as engine may hydrostatically lock.
- Always repair lowest fault number (check engine light) or first fault displayed (DRB-II), first.
- Always perform indicated verification test after repairs are made.
ENTERING ON-BOARD DIAGNOSTICS
- Start engine (if possible). Move transmission shift lever through all positions, ending in Park. Turn A/C switch on, then off (if equipped).
- Turn engine off. Without starting engine again, turn ignition on, off, on, off and on. Record 2-digit fault codes as displayed by flashing check engine light.
- For example, Code 23 is displayed as flash, flash, 4 second pause, flash, flash, flash. After a slightly longer pause, any other codes stored are displayed in numerical order.
- Once check engine light begins to flash fault codes, it cannot be stopped. If you loose count, it will be necessary to start over. Code 55 indicates end of fault code display. See «FAULT CODES»(/dodge/dakota-shelby/1989-1989/remont/testing-diagnostics/#25l-tbi-tests-wcodes) in this article.
Using DRB-II
- Attach DRB-II Tester (C-4805 ) to self-test connector. Connector is located in engine compartment near left shock tower.
- Start engine (if possible). Move transmission shift lever through all positions, ending in Park. Turn A/C switch on, then off (if equipped).
- Turn engine off. Without starting engine again, turn ignition on. Enter vehicle model year and engine size. Read fault data on DRB-II. Refer to «FAULT CODES»(/dodge/dakota-shelby/1989-1989/remont/testing-diagnostics/#25l-tbi-tests-wcodes) in this article.
DRB-II Switch Test Mode
The SMEC can only recognize high and low states on switch circuits. SMEC cannot tell the difference between an open or short circuit, or a defective switch.
The DRB-II display must change between "00" and "88" and flash check engine light when brake switch, gear shift selector and A/C switch (if equipped) are activated and released.
DRB-II Read Input States
This state on DRB-II allows technician to read input states of Z1 voltage (ignition input) sense, park/neutral switch, brake switch, A/C switch and speed control resume, on/off and set switches. DRB-II will display "INPUT LOW" or "INPUT HIGH" as SMEC senses component status changing.
DRB-II Read Output States
This state on DRB-II allows technician to read output states of speed control vacuum solenoid, purge solenoid, Part Throttle Unlock (PTU) solenoid, A/C clutch relay, radiator fan relay, ASD relay, check engine light, speed control vent solenoid and EGR solenoid. DRB-II will display "ENERGIZED" OR "DE-ENERGIZED" as SMEC senses component status changing.
DRB-II Actuate Solenoids & Relays
This state on DRB-II allows SMEC to actuate radiator fan relay, A/C clutch relay, ASD relay, purge solenoid, speed control servo solenoids, Part Throttle Unlock (PTU) solenoid and EGR solenoid. With tester in this state, SMEC can also actuate all solenoids and relays simultaneously. This test allows technician to visually and physically observe components under operation.
DRB-II Actuate Outputs
This state on DRB-II allows SMEC to actuate ignition coil, fuel injector, AIS motor open and close, alternator field, tachometer output (tach should read 1364 RPM) and fuel monitor signal. During this test, DRB-II will read "ACTUATING".
DRB-II Read Sensor Voltages
This state on DRB-II allows technician to read battery temperature sensor, oxygen sensor, coolant temperature sensor, TPS sensor, minimum throttle position in volts, battery voltage, MAP sensor and throttle body temperature sensor in volts.
DRB-II Read Sensor Values
This state on DRB-II allows technician to read throttle body temperature sensor in degrees Fahrenheit or centigrade, coolant temperature in degrees Fahrenheit or centigrade, manifold pressure in inches of vacuum or kilopascals, AIS motor in steps, added adaptive fuel in microseconds, adaptive fuel factor in percent, barometric pressure in inches of mercury or or kilopascals, engine speed in RPM, SMEC spark advance in degrees, vehicle speed given in MPH and oxygen sensor state given as center, rich or lean.
DRB-II Set Engine RPM
This state on DRB-II allows technician to set engine RPM at a fixed speed from 900-2000 in 100 RPM increments. This allows for accuracy of AIS motor control to be checked.
DRB-II Minimum Airflow Speed
This state on DRB-II allows technician to completely close AIS motor to check minimum idle speed.
DRB-II Emissions EMR Tests
This state on DRB-II allows technician to reset emission reminder light and mileage. This is only used on trucks.
DRB-II Read Module Information
This state on DRB-II allows technician to read SMEC part number and application.
Blank Message Screen
- Connect DRB-II to a different vehicle. If message screen is still blank, DRB-II or cable adapter is faulty. Substitute to find faulty component. If message screen is not blank, DRB-II and cable adapter are functioning properly.
- Inspect diagnostic connector for proper wire placement, damaged terminals or pushed out pins. Repair as necessary. If connector is okay, check Black/White ground wire of diagnostic connector for continuity to ground. Repair as necessary.
Scheme 43
"NO RESPONSE" Message
- Disconnect SMEC 60-pin connector. Ensure ignition is turned on. Using an ohmmeter, check Pink wire of diagnostic connector for continuity to SMEC 60-pin connector cavity No. 51.
- Check Light Green wire of diagnostic connector for continuity to SMEC 60-pin connector cavity No. 31. If continuity is not present, repair circuit as necessary. If continuity is present, replace SMEC. Attempt retest.
"RAM TEST FAILURE" Message
Replace DRB-II.
"CARTRIDGE ERROR" Message
Replace DRB-II cartridge.
"KEY PAD TEST FAILURE" Message
Power up DRB-II again with fingers off keypad. If error message returns, replace DRB-II.
"HIGH OR LOW BATTERY" Message
Correct condition of vehicle battery and reconnect DRB-II.
CLEARING CODES
Using DRB-II, select test "ERASE FAULT DATA". Press "YES" key on DRB-II. DRB-II will display "ARE YOU SURE? YES/NO". Press "YES" key. Tester will display "ERASING FAULT DATA X". When DRB-II is finished erasing fault codes, it will display "FAULT DATA ERASED".
If DRB-II is not available, fault codes may be cleared by allowing 50-100 key on/off cycles to occur. This will allow SMEC to clear fault codes.
Scheme 44
EMISSION MAINTENANCE REMINDER (EMR) LIGHT RESET PROCEDURE
- The Emission Maintenance Reminder (EMR) light is designed to be a reminder to service the vehicle emissions control system. It is not an emissions warning system, only a reminder to perform emissions servicing.
- The components to be serviced include the EGR system, PCV valve, oxygen sensor and some vacuum operated components. EMR light will illuminate after a predetermined mileage.
- Using DRB-II (C-4805 ), select "EMISSIONS EMR TESTS". Select "EMR MEMORY CHECK". Press "F1" or "F2" key on DRB-II until display reads, "RESET EMR LIGHT". Press "YES" key.
- Display will read, "RESET EMR LIGHT ARE YOU SURE? YES, NO". Press "YES" key. When DRB-II is finished resetting EMR light, display will read "EMR LIGHT RESET".
EMISSION MAINTENANCE REMINDER (EMR) MILEAGE TRANSFER
- When vehicle engine controller is replaced, vehicle mileage must be copied from odometer to a memory location within the replacement engine controller. Transfer of vehicle mileage will enable new engine controller to operate EMR light properly.
- Using DRB-II (C-4805 ), enter "EMISSIONS EMR TESTS". Press "YES" key. Select test item "EMR MEMORY CHECK". Press "YES" key. DRB-II display will read "EMR MEMORY CHECK ARE YOU SURE ? YES, NO". Press "YES" key.
- DRB-II will display "IS INSTRUMENT PANEL MILEAGE BETWEEN 9953 AND 10051 ?". If vehicle mileage is within specification, EMR memory check is complete. Press "YES" key. If vehicle mileage is not within specification, go to next step.
- Press "NO" key. DRB-II will display "DO YOU WANT TO CORRECT EMR MILEAGE ?". Press "YES" key. DRB-II will display "ENTER MILEAGE SHOWN ON INSTRUMENT PANEL USE ENTER KEY TO END".
- Enter vehicle mileage. DO NOT enter tenths. When correct vehicle mileage is entered, press "Enter" key. DRB-II will ask for verification of mileage entry. If mileage entry was accurate, press "Enter" key. DRB-II will display "EMR MEMORY CHECK TEST COMPLETE". Vehicle must travel at least 8 miles for reset to occur.
DTC IDENTIFICATION
| CODE | DISPLAY ON DRB-II | FAULT CONDITION |
|---|---|---|
| 11 | IGN REFERENCE SIGNAL | No Distributor Referencesignal Picked Up During Cranking. |
| 12 | Number of key-ons since last fault or since faults were erased. | Direct Battery Input To SMEC Was Disconnected Within Last 50-100 Ignition Key-Ons. |
| 13 | MAP PNEUMATIC SIGNAL | No Difference In MAP Sensorsignal Is Detected. |
| 13 | MAP PNEUMATIC CHANGE | No Difference Is Detected Between Map Reading And Stored Barometric Pressure Reading |
| 14 | MAP VOLTAGE TOO LOW | MAP Sensor Input Less Than Minimum Acceptable Voltage. |
| 14 | MAP VOLTAGE TOO HIGH | MAP Sensor Input More Than Maximum Acceptable Voltage. |
| 15 | VEHICLE SPEED SIGNAL | No Distance Sensor Signal Detected With Road Load. Conditions |
| 16 | BATTERY INPUT SENSE | Battery Voltage Sense Input Not Detected With Engine Running. |
| 17 | LOW ENGINE TEMP | Coolant Temperature Stays Below Normal Operating Temperature During Vehicle Operation. |
| 21 | OXYGEN SENSOR SIGNAL | No Rich Or Lean Signal Is Detected From O2 Sensor Input. |
| 22 | COOLANT VOLTAGE LOW | Coolant Temp. Sensor Input Below Minimum Acceptable Voltage. Coolant Temp. |
| 22 | COOLANT VOLTAGE HIGH | Coolant Temp. Sensor Input Above Maximum Acceptable Voltage. |
| 23 | T/B TEMP VOLTAGE LOW | Throttle Body Temperature Sensor Input Less Than Minimum Acceptable Voltage. |
| 23 | T/B TEMP VOLTAGE HI | Throttle Body Temperature Sensor Input More Than Maximum Acceptable Voltage. |
| 24 | TPS VOLTAGE LOW | TPS Sensor Output Less Than Minimum Acceptable Voltage. |
| 24 | TPS VOLTAGE HIGH | TPS Sensor Output More Than Maximum Acceptable Voltage. |
| 25 | AIS MOTOR CIRCUITS | Shorted Condition Detected Inone Or More AIS Control Circuits. |
| 26 | INJ 1 PEAK CURRENT | High resistance detected in injector output circuit. |
| 27 | INJ 1 CONTROL CIRCUIT | Injector Output Driver Stage Does Not Respond Correctly To SMEC Control Signal. |
| 31 | PURGE SOLENOID CKT | Open Or Shorted Condition Is Detected In Purge Solenoid. Circuit |
| 32 | EGR SOLENOID CIRCUIT | Open Or Short Is Detected In EGR Solenoid Circuit (CA Only). |
| 32 | EGR SYSTEM FAILURE | SMEC Did Not Detect Required Air/Fuel Change During Diagnostic Test (CA Only). |
| 33 | A/C CLUTCH RELAY CKT | Open Or Shorted Condition Detected In A/C Clutch Relay Circuit. |
| 34 | S/C SERVO SOLENOIDS | Open Or Shorted Condition Detected In Speed Control Vacum Or Vent Solenoid Circuits. |
| 35 | RADIATOR FAN RELAY | Open Or Shorted Condition Detected In Radiator Fan Relay Circuit. |
| 37 | PTU SOLENOID CIRCUIT | Open Or Shorted Condition Detected In Torque Converter Part Throttle Unlock Solenoid Circuit. |
| 41 | CHARGING SYSTEM CKT | Output Driver Stage Does Not Respond Correctly To Voltage Regulator Control Signal. |
| 42 | ASD RELAY CIRCUIT | Open Or Shorted Condition Detected In Asd Relay Circuit. |
| 43 | IGNITION CONTROL CIRCUIT | Output Driver Stage For Ignition Coil Does Not Respond Properly To Dwell Control Signal. |
| 44 | FJ2 VOLTAGE SENSE | No FJ2 Voltage Present At Logic Board During SMEC Operation. |
| 46 | BATTERY VOLTAGE HIGH | Battery Voltage Sense Input More Than Target Charging Voltage During Engine Operation. |
| 47 | BATTERY VOLTAGE LOW | Battery Voltage Sense Input Less Than Target Charging Voltage During Engine Operation. |
| 51 | LEAN F/A CONDITION | Oxygen Sensor Input Indicates Lean Air/Fuel Ratio During Engine Operation. |
| 52 | RICH F/A CONDITION or EXCESSIVE LEANING | Oxygen Sensor Input Indicates Rich Air/Fuel Ratio During Engine Operation. Adaptive Fuel Value Leaned Excessively From A Sustained Rich Condition. |
| 53 | INTERNAL SELF-TEST | SMEC Detects Internal Failure. |
| 55 | — | Completion Of Fault Code Display By Check Engine Light. |
| 62 | EMR MILEAGE ACCUM | Attempt Is Unsuccessful To Update EMR Mileage In Smec Eeprom. |
| N/A | FAULT CODE ERROR | DRB-II Does Not Recognize Fault Identification. |
DTC IDENTIFICATION
Note. The following trouble shooting charts and illustrations are courtesy of Chrysler Motors.
NO START TEST INFORMATION
Note. Because of limited space in the menu screen, NO START tests will be titled NS. This will allow a description of the test to appear on the menu.
NS1 - Checking For Spark At Plugs, Coils, & Fuel At TBI. Scheme 45
NS2 - Checking For Fuel From Injector & Fuel Control Faults. Scheme 46
NS3 - Checking SMEC, Wet Plugs & Engine Timing. Scheme 47
NS4 (1 of 3) - Checking Ignition Coil Driver, Open Circuits & Defective SMEC. Scheme 48
NS4 (2 of 3) - Checking Coil Driver & SMEC at 60-Pin Connector. Scheme 49
NS4 (3 of 3) - Checking Ignition Coil Driver, Open Circuits & Defective SMEC (Cont.). Scheme 50
NS5 - Checking For Power Feed To Coil Primary, Primary Coil Circuits & Coil. Scheme 51
NS6 (1 of 2) - Fuel Pressure, TPS, Fuel Pump & Fuel Circuits. Scheme 52
NS6 (2 of 2) - Fuel Pressure, TPS, Fuel Pump & Fuel Circuits (Cont.). Scheme 53
NS7 (1 of 3) - Injector Driver Circuits Z1 & Y11 & Fuel Injector. Scheme 54
NS7 (2 of 3) - Injector Driver Circuits Z1 & Y11 & Fuel Injector (Cont.). Scheme 55
NS7 (3 of 3) - Injector Driver Circuits Z1 & Y11 & Fuel Injector (Cont.). Scheme 56
NS8 (1 of 2) - Injector Interface Fault & Control Circuit K16. Scheme 57
NS8 (2 of 2) - Injector Interface Fault & Control Circuit K16 (Cont.). Scheme 58
NS1 (1 of 2) - Flooding Injector Check, Control Circuits & Defective Pressure Regulator. Scheme 59
NS1 (2 of 2) - Flooding Injector Check, Control Circuits & Defective Pressure Regulator (Cont.). Scheme 60
NS10 - Checking System For Faults. Scheme 61
NS11 (1 of 4) - System Power & Ground, Shorted MAP, SMEC & Distributor Pick-UP. Scheme 62
NS11 (2 of 4) - System Power & Ground, Shorted MAP, SMEC & Distributor Pick-UP (Cont.). Scheme 63
NS11 (3 of 4) - Location Of Distributor Pick-Up Coil. Scheme 64
NS11 (4 of 4) - System Power & Ground, Shorted MAP, SMEC & Distributor Pick-UP (Cont.). Scheme 65
NS12 (1 of 2) - Distributor Pick-Up & Connecting Circuits. Scheme 66
NS12 (2 of 2) - Distributor Pick-Up & Connecting Circuits (Cont.). Scheme 67
NS13 (1 of 3) - ASD Relay & Pull-In Coil Circuits K14 & K19. Scheme 68
NS13 (2 of 3) - Location Of ASD Relay (Caravan & Voyager). Scheme 69
NS13 (3 of 3) - Location Of ASD Relay (Dakota). Scheme 70
NS1 (1 of 2) - Power Circuit K14 To Pull-In Coil & ASD Relay. Scheme 71
NS1 (2 of 2) - Power Circuit K14 To Pull-In Coil & ASD Relay (Cont.). Scheme 72
NS15 (1 of 2) - Power Feed Circuits J2 & Z1 To ASD Relay & Defective ASD Relay. Scheme 73
NS15 (2 of 2) - Power Feed Circuits J2 & Z1 To ASD Relay & Defective ASD Relay (Cont.). Scheme 74
NSVER - No Start Verification. Scheme 75
DRIVEABILITY TEST INFORMATION
Note. Because of limited space in the menu, DRIVEABILITY tests will be titled DR. This will allow a description of the test to appear on the menu.
DR1 (1 of 10) - Checking System For Faults. Scheme 76
DR1 (2 of 10) - Checking System For Faults (Cont.). Scheme 77
DR1 (3 of 10) - Checking System For Faults (Cont.). Scheme 78
DR1 (4 of 10) - Checking System For Faults (Cont.). Scheme 79
DR1 (5 of 10) - Checking System For Faults (Cont.). Scheme 80
DR1 (6 of 10) - Checking System For Faults (Cont.). Scheme 81
DR1 (7 of 10) - Checking System For Faults (Cont.). Scheme 82
DR1 (8 of 10) - Checking System For Faults (Cont.). Scheme 83
DR1 (9 of 10) - Checking System For Faults (Cont.). Scheme 84
DR1 (10 of 10) - Checking System For Faults (Cont.). Scheme 85
DR2 (1 OF 15) - Checking Output Circuits of SMEC. Scheme 86
DR2 (2 OF 15) - Location of Solenoids (Caravan & Voyager). Scheme 87
DR2 (3 OF 15) - Location of Solenoids (Dakota). Scheme 88
DR2 (4 OF 15) - Location of PTU Solenoid (Dakota Only). Scheme 89
DR2 (5 OF 15) - Checking Shift Indicator Light & SMEC Output Circuits. Scheme 90
DR2 (6 OF 15) - Checking Brake Switch Input Circuit To SMEC. Scheme 91
DR2 (7 OF 15) - Checking Brake Switch Input Circuit To SMEC (Cont.). Scheme 92
DR2 (8 OF 15) - Checking Switch Inputs To SMEC. Scheme 93
DR2 (9 OF 15) - Location Of Quick-Disconnect Connector. Scheme 94
DR2 (11 OF 15) - Checking Emission Maintenance Reminder Light. Scheme 96
DR2 (12 OF 15) - Checking AIS Motor Operation. Scheme 97
DR2 (13 OF 15) - Checking AIS Motor Operation (Cont.). Scheme 98
DR2 (14 OF 15) - Checking SMEC Ground Circuits. Scheme 99
DR2 (15 OF 15) - Location Of Ground Circuits On 60-Pin & 14 Pin Connectors. Scheme 100
DR3 - Intermittent Test For Solenoids & Relays. Scheme 101
DR4 - Intermittent Test For MAP Sensor. Scheme 102
DR5 - Intermittent Test For Sensors. Scheme 103
DR6 - Intermittent Test For Injectors & AIS Motor. Scheme 104
DR7 - Checking For Fault Message "MAP PNEUMATIC SIGNAL". Scheme 105
DR8 - Checking For Fault Message "MAP PNEUMATIC CHANGE". Scheme 106
DR9 - Checking For Fault Message "MAP VOLTAGE LOW". Scheme 107
DR10 - Checking For Fault Message "MAP VOLTAGE TOO HIGH". Scheme 108
DR11 (1 of 3) - Checking For Fault Message "VEHICLE SPEED SIGNAL". Scheme 109
DR11 (2 of 3) - Checking For Fault Message "VEHICLE SPEED SIGNAL". Scheme 110
DR11 (3 of 3) - Location Of 50-Pin Connector. Scheme 111
DR12 - Location Of 50-Pin Connector. Scheme 112
DR13 - Checking For Fault Message "COOLANT VOLTAGE LOW". Scheme 113
DR14 - Checking For Fault Message "COOLANT VOLTAGE HIGH". Scheme 114
DR15 - Checking For Fault Message "T/B TEMP VOLTAGE LOW". Scheme 115
DR16 - Checking For Fault Message "T/B TEMP VOLTAGE HI". Scheme 116
DR17 - Checking For Fault Message "TPS VOLTAGE LOW". Scheme 117
DR19 (1 of 2) - Checking For Fault Message "AIS MOTOR CIRCUITS". Scheme 118
DR19 (2 of 2) - Checking For Fault Message "AIS MOTOR CIRCUITS" (Cont.). Scheme 119
DR20 (1 of 4) - Checking For Fault Message "PURGE SOLENOID CKT". Scheme 120
DR20 (1 of 4) - Checking For Fault Message "PURGE SOLENOID CKT" (Cont.). Scheme 121
DR21 - Checking For Fault Message "EGR SOLENOID CIRCUIT". Scheme 122
DR22 (1 of 5) - Checking For Fault Message "EGR SYSTEM FAILURE" (Cont.). Scheme 123
DR22 (2 of 5) - Checking EGR Backpressure Valve. Scheme 124
DR22 (5 of 5) - Checking For Fault Message "EGR SYSTEM FAILURE" (Cont.). Scheme 125
DR23 (1 OF 2) - Checking For Fault Message "A/C CLUTCH RELAY CKT". Scheme 126
DR23 (2 OF 2) - Checking For Fault Message "A/C CLUTCH RELAY CKT" (Cont.). Scheme 127
DR24 - Checking A/C & Fan Relays. Scheme 128
DR25 - Checking For Fault Message "RADIATOR FAN RELAY". Scheme 129
DR26 (1 of 3) - Checking For Fault Message "PTU SOLENOID CIRCUIT" (Cont.). Scheme 130
DR26 (2 of 3) - Location of PTU Solenoid (Caravan & Voyager Only). Scheme 131
DR26 (3 of 3) - Checking For Fault Message "PTU SOLENOID CIRCUIT" (Cont.). Scheme 132
DR27 - Checking For Fault Message "FJ2 VOLTAGE SENSE". Scheme 133
DR28 - Check For Fault Messages "EMR MILEAGE ACCUM" & "EEPROM WRITE DENIED". Scheme 134
DR29 (1 of 6) - Checking Sensor Calibrations (Cold). Scheme 135
DR29 (2 of 6) - Checking Sensor Calibrations (Cold - Cont.). Scheme 136
DR29 (3 of 6) - Checking Spark Plugs (Cold). Scheme 137
DR29 (4 of 6) - Checking Heated Air Intake System (Cold). Scheme 138
DR29 (5 of 6) - Checking Heated Air Intake System (Cold - Cont.). Scheme 139
DR29 (6 of 6) - Testing Air Cleaner Temperature Sensor. Scheme 140
DR30 (1 of 4) - Checking Sensor Calibrations (Warm). Scheme 141
DR30 (2 of 4) - Checking Sensor Calibrations (Warm). Scheme 142
DR30 (3 of 4) - Checking Heated Air Intake System. Scheme 143
DR31 (1 of 3) - Checking EGR Valve Operation (Warm). Scheme 144
DR31 (2 of 3) - Checking EGR Valve Operation (Warm - Cont.). Scheme 145
DR31 (3 OF 3) - View Of EGR Solenoid Vacuum Connector. Scheme 146
DR32 - Checking Secondary Ignition System. Scheme 147
DR33 (1 of 5) - Checking Basic Timing & Fuel System. Scheme 148
DR33 (2 of 5) - Checking Basic Timing & Fuel System (Cont.). Scheme 149
DR33 (3 of 5) - Connecting Fuel Pressure Gauge To Throttle Body. Scheme 150
DR33 (4 of 5) - Checking Basic Timing & Fuel System (Cont.). Scheme 151
DR33 (5 of 5) - Location of Fuel Return Hose. Scheme 152
DR34 (1 of 4) - Checking Oxygen Sensor Operation. Scheme 153
DR34 (2 of 4) - Checking Oxygen Sensor Operation (Cont.). Scheme 154
DR34 (3 of 4) - Checking Throttle Body For Leakage. Scheme 155
DR34 (4 of 4) - Location of Cavity No. 23 On 60-Pin Connector. Scheme 156
DR35 (1 of 2) - Checking Throttle Minimum Airflow. Scheme 157
DR35 (2 of 2) - Checking Throttle Minimum Airflow (Cont.). Scheme 158
At this point in the DRIVEABILITY TESTS you have determined that all of the engine control systems are operating as they were designed. Therefore, they are NOT THE CAUSE OF THE DRIVEABILITY PROBLEM.
The following items should be checked as possible causes
- ENGINE VACUUM - Must be at least 13 inches in neutral.
- ENGINE VALVE TIMING - Set to specifications.
- ENGINE COMPRESSION - To specifications.
- ENGINE EXHAUST SYSTEM - Must be free of any restrictions.
- ENGINE PCV SYSTEM - Must flow freely.
- ENGINE DRIVE SPROCKETS - Ensure they all are in good condition.
- TORQUE CONVERTER STALL SPEED - To specifications.
- POWER BRAKE BOOSTER - No internal vacuum leaks.
- FUEL CONTAMINATION - Check for high alcohol and water content.
- TECHNICAL SERVICE BULLETINS - Any that may apply to the vehicle.
Any one or more of these items can create a driveability related problem. They can not be overlooked as possible causes.
VERIFICATION TEST INFORMATION
Note. Because of limited space in the menu screen, DRIVEABILITY VERIFICATION tests will be titled VER. This will allow a description of the test to appear on the menu.
VER1 (1 of 2) - Driveability Verification Test 1. Scheme 159
VER1 (2 of 2) - Driveability Verification Test 1 (Cont.). Scheme 160
VER2 (1 of 2) - Driveability Verification Test 2. Scheme 161
VER2 (2 of 2) - Driveability Verification Test 2 (Cont.). Scheme 162
SP1 - CHECKING SPEED CONTROL SYSTEM FOR FAULT CODES
Note. Because of limited space in the menu screen, SPEED CONTROL tests will be titled SP. This will allow a description of the test to appear on the menu.
SP1 - Checking Speed Control System For Fault Codes. Scheme 163
SP2 (1 of 3) - Checking For Fault Code 34. Scheme 164
SP2 (2 of 3) - View Of Brake Switch Connector. Scheme 165
SP2 (3 of 3) - Checking For Fault Code 34 (Cont.). Scheme 166
SP3 - Testing Speed Control Switch. Scheme 167
SP4 (1 of 4) - Testing Brake Switch Circuit. Scheme 168
SP4 (2 of 4) - Testing Park/Neutral Input. Scheme 169
SP4 (3 of 4) - Testing Servo Ground. Scheme 170
SP4 (4 of 4) - Testing Servo Actuator. Scheme 171
SP5 (1 of 2) - Testing On/Off Switch & Stalk Feed. Scheme 172
SP5 (2 of 2) - View Of Speed Control Switch Connector. Scheme 173
SP6 - Testing "RESUME" Switch. Scheme 174
SP7 - Testing "SET" Switch. Scheme 175
CH1 - CHECK CHARGING SYSTEM FOR FAULT CODES
Note. Because of limited space in the menu screen, CHARGING SYSTEM tests will be titled CH. This will allow a description of the test to appear on the menu.
CH1 - Checking Charging System For Fault Codes. Scheme 176
CH2 - Checking For Fault Code 16. Scheme 177
CH3 (1 of 2) - Checking For Fault Code 46. Scheme 178
CH3 (2 of 2) - Checking For Fault Code 46 (Cont.). Scheme 179
CH4 (1 of 5) - Checking For Fault Code 47. Scheme 180
CH4 (2 of 5) - Location of Alternator Field Terminals. Scheme 181
CH4 (3 of 5) - Location of J-2 Splice (Caravan & Voyager). Scheme 182
CH4 (4 of 5) - Location of J-2 Splice (Dakota). Scheme 183
CH4 (5 of 5) - Checking For Fault Code 47 (Cont.). Scheme 184
CH5 (1 of 2) - Check For Intermittent Fault Codes. Scheme 185
CH5 (2 of 2) - Check For Intermittent Fault Codes (Cont.). Scheme 186
CH6 - Checking Charging System With No Fault Codes. Scheme 187
Caravan & Voyager 2.5L TBI Wiring Diagram. Scheme 188
Dakota 2.5L TBI Wiring Diagram. Scheme 189
Removal & Installation
Disconnect negative battery cable. Disconnect 4-pin connector on AIS. Remove 2 screws and AIS motor from throttle body. Ensure "O" ring is removed with AIS motor. To install, reverse removal procedure. Ensure that pintle is in retracted position, measuring not more than 1" (25 mm).
ASD relay is located on left fenderwell. Disconnect wiring harness from relay. Remove attaching screws and component. To install, reverse removal procedure.
Remove vacuum hose and screws from sensor. Remove electrical connector from sensor. Remove sensor from underhood. To install, reverse removal procedure.
Oxygen sensor is located in exhaust manifold. Use Wrench (C-4907) to remove sensor. Threads in exhaust manifold must be cleaned with a tap prior to installation of sensor. If old sensor is being reinstalled, threads on sensor must be coated with anti-seize compound. Tighten sensor to 20 ft. lbs. (27 N.m).
Remove air cleaner duct from SMEC. Remove battery and 2 module mounting bolts. Remove 14-pin and 60-pin wiring connectors from module. Remove module. To install, reverse removal procedure.
Scheme 190
Remove air cleaner. Disconnect throttle cables from throttle body. Remove 2 screws from throttle cable bracket. Lay throttle cable bracket aside. Disconnect electrical connector from sensor. Unscrew sensor from throttle body.
Disconnect negative battery cable and remove air cleaner. Disconnect 3-pin connector at throttle position sensor. Remove 2 screws mounting throttle position sensor to throttle body. Lift throttle position sensor from throttle shaft. To install, reverse removal procedure.
Scheme 191
See also:
• FAULT CODES
• CLEARING CODES
• ENTERING ON-BOARD DIAGNOSTICS
• 13
• 13
• 14
• 14
• 22
• 22
• 23
• 23
• 24
• 32
• 35
• 44