Engine Controls - Self Diagnostics: Other — Dodge Durango I (1997-2003)

Monitored Circuits

The Powertrain Control Module (PCM) contains electronic circuit monitors that monitor fuel, vehicle emissions, engine and ignition system performance. Monitors use information from various sensor circuits for system monitoring. Monitors do not indicate a specific component failure, but do indicate an implied failure within a specified system, and that the problem must be diagnosed. If any monitor detects a problem affecting vehicle emissions, a Diagnostic Trouble Code (DTC) will be set in PCM after 2 consecutive trips with the malfunction present. For additional information for trip definition, see TRIP DEFINITION . The following monitors are used.

Engine Misfire Monitor
Fuel System Monitor
Oxygen Sensor Monitor
Oxygen Sensor Heater Monitor
Catalyst Monitor
EVAP System Leak Detection Monitor

The PCM will erase or clear DTC once MIL is turned off. For additional information for DTC erasure, see DTC PRIORITY & DTC SELF-ERASURE .

Trip Definition

A trip has different meanings depending on what the circumstances are. If MIL is off, a trip is defined as when oxygen sensor monitor and catalyst monitor have been completed in the same drive cycle. When any emission related DTC is set, the MIL is turned on. When MIL is on, it takes 3 good trips to turn the MIL off. In this case it depends on what type of DTC is set to identify what a trip is.

If MIL is on and a DTC was set by fuel monitor or misfire monitor, the vehicle must be operated in SIMILAR CONDITIONS WINDOW for a specified amount of time to be considered a good trip. SIMILAR CONDITIONS WINDOW displays information about engine operation during a monitor. If a non-continuous OBD-II monitor such as: oxygen sensor monitor, catalyst monitor, purge flow monitor, leak detection pump monitor or oxygen sensor heater monitor fails twice in a row and turns on the MIL, re-running that monitor which previously failed on next engine start-up and passing the monitor is considered to be a good trip. If any other emission related DTC which is not an OBD-II monitor is set, a good trip is considered to be when oxygen sensor monitor or catalyst monitor have been completed, or 2 minutes of engine run times exists and oxygen sensor monitor and catalyst monitor have been stopped from running. Trips may be read on the scan tool. For additional information for trip displays on scan tool, see TRIP INDICATORS .

It can take up to 2 failures in a row to turn on the MIL. After MIL is turned on, it takes 3 good trips to turn the MIL off. After MIL is off, the PCM will erase or clear the DTC after 40 warm-up cycles. A warm-up cycle is defined as the engine is started, an increase of 40°F (4°C) in engine coolant temperature exists after engine is started and engine coolant temperature reaches at least 160°F (71°C).

Trip Indicators

Trip indicators may be displayed on scan tool. A trip is essential for running the monitors and turning off the MIL. A trip is a set of vehicle operating conditions that must be met for a specified monitor to run. A trip begins with a cycle of ignition key. Trip indicators consist of good trip counters. Good trip counters are: specific good trip, fuel system good trip, misfire good trip and warm-up cycles.

On specific good trips, the term good trip has different meanings. If MIL is off, a trip is defined as when oxygen sensor monitor and catalyst monitor have been completed in the same drive cycle. If MIL is on and a DTC was set by fuel monitor or misfire monitor, the vehicle must be operated in the SIMILAR CONDITIONS WINDOW for a specified amount of time to be considered a good trip. SIMILAR CONDITIONS WINDOW displays information about engine operation during a monitor. If MIL is on and a DTC was set by task manager commanded once per trip monitor such as oxygen sensor monitor, catalyst monitor, purge flow monitor, leak detection pump monitor or oxygen sensor monitor, a good trip is when the monitor passed on next engine start-up. If MIL is on and any other emission related DTC which is not an OBD-II monitor is set, a good trip is considered to be when oxygen sensor monitor or catalyst monitor have been completed, or 2 minutes of engine run times exists and oxygen sensor monitor and catalyst monitor have been stopped from running.

On fuel system good trips, engine must be in closed loop, operating in SIMILAR CONDITIONS WINDOW and short term multiplied by long term must be less than threshold for a predetermined time. SIMILAR CONDITIONS WINDOW displays information about engine operation during a monitor. If all of these conditions exist, PCM will count this as a good trip. Good trip must exist 3 times before MIL will shut off the MIL.

On misfire good trip, vehicle must be operated in the SIMILAR CONDITIONS WINDOW and engine must operate for 1000 revolutions without a misfire. If all of these conditions exist, PCM will count this as a good trip. Good trip must exist 3 times before MIL will shut off the MIL.

On warm-up cycles, once MIL has been turned off by good trip counter, PCM switches to warm-up counter which may be viewed on scan tool. Warm-up cycles are used to erase DTC and freeze frame data. A warm-up cycle is defined as the engine is started, an increase of 40°F (4°C) in engine coolant temperature exists after engine is started and engine coolant temperature reaches at least 160°F (71°C). After 40 warm-up cycles with no malfunction, PCM will erase the DTC.

Non-Monitored Circuits

PCM does not monitor all circuits, conditions and systems that could cause a malfunction or driveability problem. However, problems with these systems may cause PCM to store DTCs for other systems or components.

For example, a fuel pressure problem will not cause a DTC directly, but could cause a rich/lean condition or misfire. This could cause PCM to store an oxygen sensor or misfire DTC. The major non-monitored circuits are identified below.

Cylinder Compression
Excessive Oil Consumption
Exhaust System
Fuel Injector Mechanical Faults
Fuel Pressure
PCM Connector Engagement
PCM System Ground
Secondary Ignition System
Throttle Body Airflow
Vacuum Assist

Hard Failures

Hard failures cause MIL to illuminate and remain on until problem is repaired. This means the defect is there every time the PCM checks that circuit or function. If MIL light comes on and remains on during vehicle operation, cause of malfunction must be determined by retrieving Diagnostic Trouble Codes (DTC). See RETRIEVING DIAGNOSTIC TROUBLE CODES . If a sensor fails, PCM will use substitute value in its calculations to continue engine operation. In this condition, commonly known as limp-in mode, the vehicle runs but driveability will not be optimum.

Intermittent Failures

Intermittent failures may cause MIL to flicker or illuminate and go out after intermittent failure goes away. However, the corresponding Diagnostic Trouble Code (DTC) will be retained in PCM memory. If related failure does not reoccur within a certain time frame, related DTC will be cleared from PCM memory. Most intermittent failures are caused by a sensor, electrical connector or wiring related problems. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES - EXCEPT DIESEL article.

SERVICE PRECAUTIONS

Before proceeding with system diagnosis, following precautions must be followed

Before performing any testing procedures, check for any related Technical Service Bulletins (TSBs).
Ensure fuel pressure is released before removing fuel line or fittings, as fuel system is under pressure and may cause personal injury.
When using DIAGNOSTIC TESTS for diagnosis, DO NOT skip any steps, or incorrect diagnosis may result. When instructed to disconnect any connector, check that the connector is clean and in good condition after disconnecting the connector. Repair or clean connector if necessary. Always perform indicated verification procedure after repairs are made. Verification tests are listed at the end of the diagnostic tests.
DO NOT use 12-volt test light when checking 5-volt or 8-volt supply circuit, CCD bus circuit, camshaft position sensor signal circuit, crankshaft position sensor signal circuit, oxygen sensor signal circuit or vehicle speed sensor signal circuit or Powertrain Control Module (PCM) may be damaged.
When using a jumper wire, ensure either jumper wire or circuit is fuse-protected.
Before disconnecting any control module connector, ensure ignition is off before removing connector.
When checking voltage or continuity at any control module, probe control module connector from pin side. DO NOT backprobe connector unless instructed to in test procedure. DO NOT probe wires through the insulation.
DO NOT cause short circuits when performing electrical tests. This may cause additional Diagnostic Trouble Codes (DTC) to be set, making diagnosis of original problem more difficult.
Use specified test equipment when performing electrical tests.
DO NOT prolong testing of fuel injectors or engine may hydrostatically lock.
If replacing Powertrain Control Module (PCM), the correct vehicle mileage and Vehicle Identification Number (VIN) must be programmed into the PCM to prevent Diagnostic Trouble Codes (DTC) from being set in Anti-Lock Brake System (ABS) module and Supplemental Restraint System (SRS) module. See «POWERTRAIN CONTROL MODULE PROGRAMMING»(ref-9482-S24921337502000102700000) under PROGRAMMING.
On 4.7L, if Transmission Control Module (TCM) is replaced, perform shift quality quick learn procedure. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION.

POWERTRAIN CONTROL MODULE PROGRAMMING

Note. If replacing Powertrain Control Module (PCM), the correct vehicle mileage and Vehicle Identification Number (VIN) must be programmed into PCM to prevent Diagnostic Trouble Codes (DTCs) from being set in Anti-Lock Brake System (ABS) module and Supplemental Restraint System (SRS) module.

To program PCM and clear DTCs from ABS and SRS modules, connect scan tool to Data Link Connector (DLC). DLC is located below driver's side of instrument panel. (Схема №1) Turn ignition on with engine off.
Using scan tool, enter correct VIN and mileage into PCM. Using scan tool manufacturer's instructions, clear DTCs from ABS and SRS modules.

SUMMARY

If no diagnostic trouble code is present but driveability problem still exists, perform TEST NTC-1: NO TROUBLE CODE TEST MENU located after Diagnostic Trouble Code (DTC) tests under DIAGNOSTIC TESTS for engine diagnosis. If after performing TEST NTC-1, problem is not identified and repaired, proceed to TROUBLE SHOOTING - NO CODES - EXCEPT DIESEL article for diagnosis by symptom.

FUEL SYSTEM PRESSURE RELEASE

CAUTION

Fuel system is under high pressure. Release fuel pressure before disconnecting any fuel lines or fuel system components.

4.7L, 5.2L & 5.9L

Remove fuel tank cap. Remove fuel pump relay from power distribution center at driver's side front corner of engine compartment, near battery. If necessary to identify fuel pump relay (Схема №41) Start engine and allow engine to idle until engine stalls. Attempt to start engine until it will no longer run. Turn ignition off.
Disconnect electrical connector at any fuel injector. Connect jumper wire between Dark Green/Orange wire electrical terminal on fuel injector and positive battery terminal.
Momentarily connect jumper wire between remaining electrical terminal on fuel injector and negative battery terminal for a few seconds. DO NOT apply voltage to fuel injector for extended time or fuel injector may be damaged. This operates fuel injector and releases fuel pressure.
Remove jumper wires. Install electrical connector on fuel injector. Fuel pressure should now be released. Reinstall fuel pump relay. Diagnostic Trouble Code (DTC) may have been stored in Powertrain Control Module (PCM) due to the removal of fuel pump relay. For clearing DTCs from PCM, see «CLEARING DIAGNOSTIC TROUBLE CODES»(ref-9482-S31175527272000102700000) under SELF-DIAGNOSTIC SYSTEM.

Programming PCM & Clearing DTCs From ABS & SRS Modules

Connect scan tool to Data Link Connector (DLC). Using scan tool, enter correct VIN and mileage into PCM. Using scan tool manufacturer's instructions, clear DTCs from ABS and SRS modules. Proceed to final procedure.

Final Procedure

Inspect vehicle to ensure all components related to the repair are properly connected. Reassemble and reconnect components as necessary. Inspect engine oil for fuel contamination. Change engine oil and filter as necessary. Attempt to start engine.
If engine starts, test is complete. If engine does not start, check for related Technical Service Bulletins (TSBs) and return to «TEST NS-SEL: NO START TEST SELECTION»(ref-9482-S18486773912000102700000) for additional testing.

Inspect vehicle to ensure all components related to the repair are properly connected. Reassemble and reconnect components as necessary.
If verification test is being performed after a No Trouble Code (NTC) test, go to next step. If verification test is being performed after a Diagnostic Trouble Code (DTC) test, go to step 4 .
Check to see if initial symptom exists. If initial symptom does not exist, repair was successful and test is complete. If initial symptom still exists or another symptom exists, repair was not successful. Check for related Technical Service Bulletins (TSBs) or flash updates for the symptom and return to «TEST NTC-1: NO TROUBLE CODE TEST MENU»(ref-9482-S18152000352000102700000) for engine diagnosis.
If PCM has not been changed, using scan tool, clear DTCs from PCM and reset all values in adaptive memory. To verify that no DTCs exist, vehicle should be road tested. If verification test is being performed for an A/C control circuit DTC, ensure A/C is turned on during road test. Perform road test for at least 5 minutes with vehicle speed of at least 40 MPH. At some point during road test, stop vehicle. Turn engine off for at least 10 seconds and then start engine and continue with road test. Ensure transmission shifts through all gears.
After road test is completed. Turn engine off. Using scan tool, check for DTCs. If no DTCs exist, test is complete. If any DTCs exist, repair is not complete. Proceed to appropriate DTC test.

Inspect vehicle to ensure all components related to the repair are properly connected. Reassemble and reconnect components as necessary.
Using scan tool, clear DTCs from PCM. To ensure no charging system problem exists, start engine. Increase engine speed to 2000 RPM for at least 30 seconds. Allow engine to idle. Shut engine off.
Using scan tool, check for DTCs. If no DTCs exist, test is complete. If repaired DTC has reset or any DTCs exist, repair is not complete. Check for related Technical Service Bulletins (TSBs) and proceed to appropriate DTC test.

Inspect vehicle to ensure all components related to the repair are properly connected. Reassemble and reconnect components as necessary. Connect scan tool to Data Link Connector (DLC). Using scan tool, clear DTCs from PCM.
To ensure no speed control system problem exists, road test vehicle at a speed more than 35 MPH. Depress steering wheel speed control ON/OFF switch to ON position. Depress and release steering wheel speed control SET switch. Verify that speed control engages. If speed control engages, go to next step. If speed control does not engage, test is not complete. Check for related Technical Service Bulletins (TSBs) and any speed control related DTCs. Perform appropriate DTC test if necessary.
With speed control engaged, depress and hold steering wheel speed control RESUME/ACCEL switch. Verify that vehicle speed increases by 2 MPH. Release RESUME/ACCEL switch. Depress and hold steering wheel speed control COAST switch. Verify that vehicle speed decreases. Release COAST switch. Go to next step.
Using caution, depress and release brake pedal. Verify that speed control disengages. Ensure vehicle speed is more than 35 MPH. Depress steering wheel speed control RESUME/ACCEL switch. Verify that previously set vehicle speed is obtained. Release steering wheel speed control RESUME/ACCEL switch. Go to next step.
Depress steering wheel speed control SET switch and ensure vehicle speed decreases. Increase vehicle speed to at least 35 MPH. Release steering wheel speed control SET switch. Verify that speed control engages and speed is maintained.
With speed control engaged, depress and release steering wheel speed control CANCEL switch. Verify that speed control disengages.
Increase vehicle speed to at least 35 MPH and engage speed control. Depress and release steering wheel speed control ON/OFF switch to OFF position. Verify that speed control disengages. Go to next step.
If all of the functions listed in steps 2) - 8) operate properly, test is complete. If any or all of the functions listed in steps 2) - 8) do not operate properly, repair is not complete. Check for related Technical Service Bulletins (TSBs) and any speed control related DTCs. Perform appropriate DTC test if necessary.

Inspect vehicle to ensure all components related to the repair are properly connected. Reassemble and reconnect components as necessary. If all DTCs have been diagnosed and repaired, go to next step. If any DTCs have not been diagnosed, perform appropriate DTC test and finish diagnosing remaining DTCs as necessary.
Ensure fuel tank is at least 1/4 full and all accessories are off. If DTC for a comprehensive component was repaired, go to next step. If a DTC for OBD-II monitor was repaired, go to step 4 .
Ensure ignition is off for at least 10 seconds. Start engine and operate engine for at least 2 minutes while noting GOOD TRIP counter. If GOOD TRIP counter changes to one or more and no new DTCs exist, repair was complete. If GOOD TRIP counter changes to zero, this indicates that DTC has reset and repair is not complete. Check for related Technical Service Bulletins (TSBs), flash updates and then proceed to appropriate DTC test.
Proper way to ensure DTC is properly repaired is to allow PCM to run the OBD-II monitor. OBD-II monitor operation may be observed on the scan tool. In order for OBD-II monitor to be run, certain pretest enabling conditions must be met. Refer to applicable OBD-II monitor pretest screen on scan tool for monitor enabling conditions.
Operate vehicle within all enabling conditions and allow applicable OBD-II monitor to run. While OBD-II monitor is running, scan tool will beep. After OBD-II monitor is complete, view the results. If OBD-II monitor ran and GOOD TRIP counter changed to one or more, repair is complete. If OBD-II monitor failed or repaired DTC has reset or any DTCs exist, repair is not complete. Check for related Technical Service Bulletins (TSBs), flash updates and then proceed to appropriate DTC test.

Inspect vehicle to ensure all components related to the repair are properly connected. Reassemble and reconnect components as necessary. If any DTCs have not been diagnosed, perform appropriate DTC test and finish diagnosing remaining DTCs as necessary. If all DTCs have been diagnosed and repaired, go to next step.
Connect scan tool to Data Link Connector (DLC). Ensure all accessories are off. Start engine and allow engine to idle. Ensure shift lever is in Park and throttle is in idle position. NOTE: Engine must remain at idle with shift lever in Park and throttle at idle position when performing LDP monitor test. LDP monitor test will only store a small leak DTC to indicate there is a problem with the system. System failure may have been caused by a large leak, but the PCM will only set the small leak DTC to indicate that a failure occurred during the test.
Using scan tool in SYSTEM TESTS mode, perform LDP MONITOR TEST and follow instructions as displayed on scan tool. If a DTC for a small leak is set, the repair is not complete. Check for related Technical Service Bulletins (TSBs) and perform appropriate DTC test. If any other DTCs were reset, perform appropriate DTC test. If no other DTCs exist and LDP monitor test passed, repair is now complete.

Inspect vehicle to ensure all components related to the repair are properly connected. Reassemble and reconnect components as necessary. If all DTCs have been diagnosed and repaired, go to next step. If any DTCs have not been diagnosed, perform appropriate DTC test and finish diagnosing remaining DTCs as necessary.
Using scan tool, monitor SIMILAR CONDITIONS WINDOW data. Attempt to duplicate the condition that causes DTC to be set. If conditions can be duplicated GOOD TRIP counter will change to one or more. If GOOD TRIP counter changes to one or more and no new DTCs exist, repair was complete. If GOOD TRIP counter changes to zero, this indicates that DTC has reset and repair is not complete. If OBD-II monitor failed or repaired DTC has reset or any DTCs exist, repair is not complete. Check for related Technical Service Bulletins (TSBs), flash updates and then proceed to appropriate DTC test.

Inspect vehicle to ensure all components related to the repair are properly connected. Reassemble and reconnect components as necessary. If all DTCs have been diagnosed and repaired, go to next step. If any DTCs have not been diagnosed, perform appropriate DTC test and finish diagnosing remaining DTCs as necessary.
Start engine and operate engine until transmission temperature is more than 110°F (43°C). Check and adjust transmission fluid level as necessary. Road test vehicle with a constant throttle opening of 20-25 percent while allowing transmission to make 1-2, 2-3 and 3-4 upshifts until vehicle speed is at 45 MPH. These upshifts must be performed at least 15 times.
Allow vehicle speed to decrease to 25 MPH and then perform 5-8 wide open throttle kickdown shifts to first gear. Allow at least 5 seconds in second or third gear between each kickdown shift. Using scan tool, monitor SIMILAR CONDITIONS WINDOW data and attempt to duplicate the condition that causes DTC to be set.
After road test is completed, using scan tool, check for DTCs. If no DTCs exist, test is complete. If repaired DTC has reset or any DTCs exist, repair is not complete. Proceed to appropriate DTC test.

Inspect vehicle to ensure all components related to the repair are properly connected. Reassemble and reconnect components as necessary. If all DTCs have been diagnosed and repaired, go to next step. If any DTCs have not been diagnosed, perform appropriate DTC test and finish diagnosing remaining DTCs as necessary.
Ensure all DTCs are clearned from Powertrain Control Module (PCM) and Transmission Control Module (TCM). Using scan tool, monitor transmission fluid temperatere. Start engine and operate engine until transmission temperature is more than 110°F (43°C). Check transmission fluid level as necessary. If necessary to add transmission fluid, add transmission fluid once transmission fluid temperature is at 180°F (82°C) to prevent overfilling.
If TCM has not been replaced, go to next step. If TCM has been replaced, perform shift quality quick learn procedure and then go to next step. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION.
Road test vehicle with a constant throttle opening of 20-25 percent while allowing transmission to make 1-2, 2-3 and 3-4 upshifts until vehicle speed is at 45 MPH while using scan tool to monitor engine RPM. These upshifts must be performed at least 15 times.
Allow vehicle speed to decrease to 25 MPH and then perform 5-8 wide open throttle kickdown shifts to first gear. Allow at least 5 seconds in second or third gear between each kickdown shift.
Using scan tool, check for DTCs during road test. If no DTCs exist, test is complete. If repaired DTC has reset or any DTCs exist, repair is not complete. Proceed to appropriate DTC test. For diagnosis of DTCs stored in TCM, see CHRYSLER 45RFE ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.

Engine Controls - Self Diagnostics: Other Dodge Durango I