Engine Controls - Self-Diagnostics - 3.0L: Other Mitsubishi Galant VIII рестайлинг

Malfunction Indicator Light (MIL)

MIL may also be referred to as Service Engine Soon light. If all systems are normal, immediately after the ignition switch is turned to ON position, MIL will illuminate for 5 seconds, then go out. When PCM determines an emissions related malfunction exists, PCM will turn the MIL on. If PCM determines that the malfunction no longer exists, it will turn the MIL off.

If MIL will not come on for bulb check or MIL stays on with no Diagnostic Trouble Codes (DTCs) present, diagnose MIL circuit malfunction. See MALFUNCTION INDICATOR LIGHT (MIL) DIAGNOSIS .

Freeze Frame Data

The conditions at the time a malfunction is detected will be stored in PCM as freeze frame data. While multiple DTCs may be recorded, only one freeze frame is recorded. DTCs are assigned a priority with fuel and misfire codes having the highest priority. Non-emissions related DTCs have the lowest priority. The DTC with the highest priority will be the one recorded in freeze frame. Freeze frame records are cleared when DTCs are erased. Freeze frame data recorded is

1. Engine Coolant Temperature
2. Engine RPM
3. Vehicle Speed
4. Long Term Fuel Trim (Displayed As Percent)
5. Short Term Fuel Trim (Displayed As Percent)
6. Fuel Control Condition (Open Or Closed Loop)
7. Calculated Load Value (Displayed As Percent)
8. DTC During Data Recording

OBD-II Drive Cycles

Manufacturer defines drive cycle as a pattern of driving that meets code set criteria for PCM to monitor a particular system/component. Drive cycle is used to verify repair by reproducing conditions during which fault occurred. There are 6 different drive cycles. These are: Catalytic Converter Monitor, EVAP System Leak Monitor, Heated Oxygen Sensor (HO2S) Monitor, EGR Monitor, Fuel Trim Monitor and Other Monitor. For the requirements to run a drive cycle, see appropriate drive cycle in OBD-II DRIVE CYCLES under VERIFYING REPAIRS. DO NOT run drive cycle if outside air temperature is less than 14°F (-10°C).

Failure Management

When main sensor malfunctions are detected, PCM will enter fail-safe mode. Default values will be substituted in PCM calculations for faulty sensor as follows

1. Volume Airflow Sensor - PCM will use engine speed (crankshaft position sensor) and Throttle Position (TP) sensor signals to determine injector drive time and basic ignition timing. Idle Air Control (IAC) motor remains in a fixed position.
2. Intake Air Temperature (IAT) Sensor Sets at a default of 77°F (25°C).
3. Throttle Position (TP) Sensor Fuel injection amount will not increase during acceleration due to unreliable TP sensor signal.
4. Engine Coolant Temperature (ECT) Sensor Sets at a default of 176°F (80°C).
5. Camshaft Position (CMP) Sensor PCM will command injectors to inject fuel into cylinders in normal firing order, but may not be synchronized with camshaft timing.
6. Barometric Pressure (BARO) Sensor Sets at a default of 30 in. Hg (101 kPa).
7. Knock Sensor Switches ignition timing from high octane to fixed at low octane.
8. Heated Oxygen Sensor (HO2S) Front Closed loop fuel control is not allowed.
9. Heated Oxygen Sensor (HO2S) Rear Allows closed loop fuel control using front HO2S signals.
10. Generator FR Terminal Generator output suppression control of electrical load is not performed.
11. Communication Line With Transaxle Control Module (TCM) Ignition timing retard control is inoperative when transaxle speeds change.
12. Misfire Detection Fuel supply is stopped to cylinder if misfiring will damage catalytic converter.

Hard Failures

Hard failures cause Malfunction Indicator Light (MIL) to illuminate and remain on until problem is repaired. If light comes on and remains on (light may flash) during vehicle operation, cause of malfunction must be determined using diagnostic (code) charts. If a sensor fails, PCM will use a substitute value in its calculations to continue engine operation. In this condition, commonly known as limp-in mode, vehicle runs but driveability will not be optimum.

SERVICE PRECAUTIONS

Before proceeding with diagnosis, following precautions must be observed

1. Ensure vehicle has a fully charged battery and functional charging system. Codes cannot be retrieved if battery voltage is too low.
2. Visually inspect connectors and circuit wiring being worked on.
3. DO NOT disconnect battery or PCM. This will erase any DTCs stored in PCM.
4. DO NOT cause short circuits when performing electrical tests. This will set additional DTCs, making diagnosis of original problem more difficult.
5. DO NOT use a test light in place of a voltmeter. Use voltmeter with 10-megohm impedance.
6. When checking for spark, ensure coil wire is NOT more than 1/4" from chassis ground. If coil wire is more than 1/4" from chassis ground, damage to vehicle electronics and/or PCM may result.
7. DO NOT prolong testing of fuel injectors. Engine may hydrostatically (liquid) lock.

IMMOBILIZER SYSTEM

If immobilizer ECU or PCM is replaced, all keys will have to be reprogrammed. If immobilizer ECU is replaced, vehicle secret code and password will need to be registered into new immobilizer ECU.

Encrypted Code Registration

1. Obtain vehicle secret code from customer or manufacturer. Connect scan tool to Data Link Connector (DLC). see scheme 1 Insert valid ignition key and turn the ignition switch to ON position. Under MAIN MENU select SYSTEM SELECT and press YES. Select IMMOBILIZER and press YES.
2. Select SPECIAL FUNC and press YES. Select PASSWORD SET and press YES. Enter vehicle secret code and 4-digit password into new immobilizer ECU. If an incorrect code is entered 5 times in a row, immobilizer ECU will detect tampering and enter start-prevention mode. Engine operation and special functions will be disabled.
3. To clear start-prevention mode, turn the ignition switch to ON position and leave in ON position for 20 minutes. Connect a battery charger if necessary. Start-prevention mode will cancel after 20 minutes. After completing encrypted code registration procedure, all ignition keys will need to be input. See «KEY ID REGISTRATION»(ref-150943-S29352642312002112700000).

Key ID Registration

Ensure all ignition keys (new and existing) for vehicle are available during key ID registration. All ignition keys will need to be input into immobilizer ECU.

1. Connect scan tool to Data Link Connector (DLC). see scheme 1 Insert valid ignition key and turn the ignition switch to ON position. Under MAIN MENU select SYSTEM SELECT and press YES.
2. Select IMMOBILIZER and press YES. Select SPECIAL FUNC and press YES. Select KEY ID REGISTR and press YES. If DTC 11 is set, scan tool will display CAN'T EXECUTE. If CAN'T EXECUTE is not displayed, go to next step. If CAN'T EXECUTE is displayed, go to DTC NO. 11: TRANSPONDER COMMUNICATION SYSTEM OR RADIO INTERFERENCE OF ENCRYPTED CODE under DIAGNOSTIC TESTS in appropriate ANTI-THEFT SYSTEMS article.
3. Scan tool will display PLEASE ENTER PASSWORD. Using arrow keys, select password. Press YES when correct 4-digit password is selected. NOTE: If an incorrect code is entered 5 times in a row, immobilizer ECU will detect tampering and enter start-prevention mode. Engine operation and special functions will be disabled. To clear start-prevention mode, turn the ignition switch to ON position and leave in ON position for 20 minutes. Connect a battery charger if necessary. Start-prevention mode will cancel after 20 minutes.
4. Scan tool will display ARE YOU READY?. Press YES to begin registration. When registration is complete, scan tool will display COMPLETE. If an error occurs during registration, scan tool will display CAN'T EXECUTE. If ignition key is already registered, scan tool will display KEY ID HAS BEEN REGISTERED.
5. Scan tool will display number of keys registered. To register additional keys (up to 8 different keys), insert next key and turn the ignition switch to ON position within 5 seconds. Then press YES on scan tool. After all ignition keys are registered, press NO on scan tool. This will complete key ID registration. Turn ignition to OFF position and leave off for a minimum of 10 seconds.
6. Check that vehicle can be started with each key. Check that no MFI or immobilizer ECU DTCs did not set. If DTCs set, repair as necessary. If no DTCs set, turn the ignition switch to LOCK position and disconnect scan tool. Procedure is complete.

MALFUNCTION INDICATOR LIGHT DOES NOT COME ON WHEN IGNITION IS TURNED TO ON POSITION

Note. If PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

MALFUNCTION INDICATOR LIGHT STAYS ON

Note. If PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

NO COMMUNICATION WITH ENGINE CONTROL MODULE/POWERTRAIN CONTROL MODULE

Note. If PCM is replaced, immobilizer code registration must be performed. See PROGRAMMING .

SUMMARY

If there are no DTCs or provisional codes and driveability symptoms exist, proceed to TROUBLE SHOOTING - NO CODES article for diagnosis by symptom or intermittent diagnostic procedures. See INTERMITTENT DIAGNOSTIC TROUBLE CODES under ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM.

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Possible Causes

1. Volume airflow sensor failed.
2. Open or shorted volume airflow sensor circuit, or loose connector.
3. PCM failed.
4. Air leak between volume airflow sensor and throttle body.

1. Volume airflow sensor failed.
2. Open or shorted volume airflow sensor circuit, or loose connector.
3. PCM failed.
4. Air leak between volume airflow sensor and throttle body.

1. Barometric pressure sensor failed.
2. Open or shorted barometric pressure sensor circuit, or loose connector.
3. PCM failed.

The most likely causes for this code to be set are

1. Barometric pressure sensor failed.
2. Open or shorted barometric pressure sensor circuit, or loose connector.
3. PCM failed.

VERIFYING REPAIRS

Note. Erasing DTCs will also erase freeze frame data and reset readiness test status.

For catalytic converter, Heated Oxygen Sensor (HO2S), EGR, fuel trim and Evaporative Emissions (EVAP) system related DTCs, it will be necessary to drive vehicle according to drive cycle that allows PCM to monitor the fault area. Clear DTCs and drive vehicle according to appropriate monitor. See appropriate monitor in OBD-II DRIVE CYCLES .

If drive cycle used to verify repair runs catalytic converter monitor, HO2S monitor, EGR monitor, fuel trim monitor, or EVAP system leak monitor, repair may be verified in one drive cycle by checking readiness test status. Readiness test status is an indicator showing whether monitor has run or not run. If PCM ran monitor and found no faults, readiness test status will display COMPLETE or READY. Repair is verified.

If PCM found fault during drive cycle, or monitor did not meet criteria to run, readiness test status will display INCOMPLETE or NOT READY. Perform drive cycle again. The second time drive cycle is run, readiness test status will display COMPLETE or READY whether or not a fault was found. It will be necessary to check for DTCs. If readiness test status does not display COMPLETE or READY after 2 drive cycles, second or both drive cycles failed to meet criteria necessary for PCM to run monitor.

For systems and components monitored by other monitor, record freeze frame data. Clear DTCs. Drive vehicle in manner approximating conditions recorded in freeze frame in order to verify repair.

Other monitor does not have readiness test status because other monitor runs continuously. Manufacturer's MUT-II Scan Tool (MB991502) provides mode 2 (increased sensitivity) and mode 5 (provisional DTCs) functions which allow repairs to be verified after one drive cycle. Generic scan tools may or may not have these functions. If scan tool does not have these functions, drive vehicle under conditions approximating freeze frame data twice, then check for DTCs.

Scan tool Mode 2 (increased sensitivity) allows single drive cycle testing of emissions related DTCs. Mode 2 commands PCM to illuminate MIL and set DTC on first occurrence of fault when code set criteria are being met. If MIL does not illuminate during drive cycle, repair is verified. Return to Mode 1 (normal) by turning ignition switch to OFF position or reselecting Mode 1. When scan tool returns to Mode 1, freeze frame data, readiness test status and DTCs are erased.

Scan tool mode 5 (provisional DTCs) can be used to verify repairs after only one drive cycle by reporting fault as provisional (pending) DTC. Mode 5 is limited to reporting faults related to misfire, fuel system and faults detected by other monitor.

Catalytic Converter Monitor

PCM monitors the deterioration of catalyst by the output frequency ratio between heated oxygen sensor (front) and heated oxygen sensor (rear).

This monitor applies to DTC P0421 and P0431. Following conditions must be met during the test

1. Atmospheric temperature is 14°F (-10°C) or more.
2. A/C switch is in OFF position.
3. Selector lever is in "D" range.

Monitor takes about 20 minutes to complete. This cycle must be completed 2 times. Run monitor as shown. (Scheme 251) Remove all test equipment from vehicle and install all components and connectors that were removed or disconnected during testing. Perform steps as follows

1. Start engine and accelerate to 45 MPH.
2. Travel 300 seconds or greater while keeping speed at 45-60 MPH.
3. Fully close throttle and decelerate to 35-40 MPH.
4. While keeping accelerator pedal opening degree constant, keep speed at 35-40 MPH for 90 seconds or more (this is when monitor runs).
5. Fully close throttle and decelerate for 10 seconds. Then, quickly accelerate until speed is 35-40 MPH. Then repeat steps 3 and 4 five more times.
6. Return vehicle to shop and Turn the ignition switch to LOCK position. Recheck for DTCs. If DTC P0421 or P0431 resets, return to appropriate repair procedure under «DIAGNOSTIC TESTS»(ref-150943-S41143158342002112700000)

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EVAP System Leak Monitor

On small leaks, the PCM monitors the leak of fuel evaporation gas by the reduction of vacuum in tank after appointed time using the fuel tank differential pressure sensor after sealing the fuel tank and the fuel line and applying vacuum.

On large leaks, the PCM monitors the leak of fuel evaporation gas by checking whether the pressure can be reduced (the amount of pressure reduction) using the fuel tank differential pressure sensor after sealing the fuel tank and the fuel line.

This monitor applies to DTCs P0441, P0442, P0451, P0452, P0453, P0455 and P0456. Following conditions must be met during the test

1. Engine coolant temperature must be 75°F (30°C) or less.
2. Atmospheric temperature is 41-113°F (5-45°C).
3. Selector lever is in "D" range.

Test may not run if fuel tank is more than 75 percent full. Monitor takes about 8 minutes to complete. This cycle must be completed 2 times. Run monitor as shown. (Scheme 252) Remove all test equipment from vehicle and install all components and connectors that were removed or disconnected during testing. Perform steps as follows

1. Start engine and accelerate to 55-60 MPH.
2. Travel for 200 seconds or more while keeping speed at 55-60 MPH.
3. While keeping accelerator pedal position constant, keep speed at 55-60 MPH for 150 seconds or more (this is when monitor runs).
4. Return vehicle to shop and Turn the ignition switch to LOCK position. Recheck for DTCs. If DTC P0441, P0442, P0451, P0452, P0453, P0455 or P0456 resets, return to appropriate repair procedure under «DIAGNOSTIC TESTS»(ref-150943-S41143158342002112700000) .

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EGR Monitor

PCM monitors the operation of EGR system by the pressure difference of intake manifold between before and after introduction of EGR using the manifold differential pressure sensor.

This monitor applies to DTC P0401. Following conditions must be met during the test

1. Engine coolant temperature must be 176°F (80°C) or greater.
2. Atmospheric temperature is 41°F (5°C) or greater.
3. Selector lever is in "D" range.
4. A/C switch is in OFF position.

Monitor takes about 10 minutes to complete. This cycle must be completed 2 times. Run monitor as shown. see scheme 114 Remove all test equipment from vehicle and install all components and connectors that were removed or disconnected during testing. Perform steps as follows

1. Start engine and accelerate to 35-40 MPH.
2. Keep speed constant at 35-40 MPH for 20 seconds or more.
3. Decelerate by closing throttle fully allowing engine speed to drop from 2000-3000 RPM to about 900 RPM. DO NOT apply brakes. DO NOT turn steering wheel or operate light switch during this time (this is when monitor runs).
4. Accelerate to 35-40 MPH, then hold speed constant for 20 seconds or more. Repeat steps 2 and 3 seven more times.
5. Return vehicle to shop and Turn the ignition switch to LOCK position. Recheck for DTCs. If DTC P0401 resets, go to «DTC P0401: EXHAUST GAS RECIRCULATION FLOW INSUFFICIENT DETECTED»(ref-150943-S15968783212002112700000) under DIAGNOSTIC TESTS.

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Fuel Trim Monitor

This monitor applies to DTCs P0171, P0172, P0174 and P0175. Following conditions must be met during the test

1. Engine coolant temperature is 176-207°F (80-97°C).
2. Atmospheric temperature is 14-140°F (-10-60°C).
3. Selector lever is in "D" range.

Monitor takes about 35 minutes to complete. This cycle must be completed 2 times. Run monitor as shown. see scheme 115 Remove all test equipment from vehicle and install all components and connectors that were removed or disconnected during testing. Perform steps as follows

1. Start engine and accelerate to 55-60 MPH.
2. Drive at 55-60 MPH for 30 minutes or more. During this period DO NOT drive at constant speed for more than 120 seconds. Carry out gradual deceleration and acceleration within every 120 second time frame.
3. Return vehicle to shop and Turn the ignition switch to LOCK position. Recheck for DTCs. If DTC P0171, P0172, P0174 or P0175 resets, return to appropriate repair procedure under «DIAGNOSTIC TESTS»(ref-150943-S41143158342002112700000) .

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Heated Oxygen Sensor Monitor

PCM monitors the deteriorated condition of the front heated oxygen sensor by checking the lean/rich switching frequency of the heated oxygen sensor.

The PCM checks the output voltage of the rear heated oxygen sensor in order to monitor whether the heated oxygen sensor output is stuck.

This monitor applies to DTCs P0132, P0133, P0137, P0138, P0139, P0152, P0153, P0158 and P0159. Following conditions must be met during the test

1. Engine coolant temperature must be 176°F (80°C) or greater.
2. Atmospheric temperature is 14°F (-10°C) or greater.
3. Selector lever is in "D" range.

Monitor takes about 5 minutes to complete. This cycle must be completed 2 times. Run monitor as shown. see scheme 116 Remove all test equipment from vehicle and install all components and connectors that were removed or disconnected during testing. Perform steps as follows

1. Start engine and accelerate to 35-40 MPH.
2. While keeping accelerator pedal position constant, keep speed at 35-40 MPH for 120 seconds or more (this is when monitor runs).
3. Return vehicle to shop and Turn the ignition switch to LOCK position. Recheck for DTCs. If DTC P0132, P0133, P0137, P0138, P0139, P0152, P0153, P0158 or P0159 resets, return to appropriate repair procedure under «DIAGNOSTIC TESTS»(ref-150943-S41143158342002112700000) .

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Other Monitor

This monitor applies to DTCs not covered by other monitors. Following conditions must be met during the test

1. Engine coolant temperature must be 176°F (80°C) or greater.
2. Atmospheric temperature is 41°F (5°C) or greater.
3. Selector lever is in "D" range.

Monitor takes about 10 minutes to complete. This cycle must be completed 2 times. Run monitor as shown. see scheme 117 Remove all test equipment from vehicle and install all components and connectors that were removed or disconnected during testing. Perform steps as follows

1. Start engine and accelerate to 35-40 MPH.
2. Drive for 5 minutes or more at 35-40 MPH.
3. Return vehicle to shop and let idle. While engine is idling, A/C switch must be in OFF position, lights and accessories must be off, steering wheel must be straight ahead, and transaxle must be in neutral. After idling for 5 minutes, Turn the ignition switch to LOCK position.
4. Recheck for DTCs. If any DTC other than P0130, P0133, P0136, P0139, P0171, P0172, P0401, P0442, P0450, P0451, P0455 or P0421 resets, return to appropriate repair procedure under «DIAGNOSTIC TESTS»(ref-150943-S41143158342002112700000) .

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