Part 2
ON BOARD DIAGNOSTIC (OBD) SYSTEM(continued)
Diagnosis Description
PERMANENT DIAGNOSTIC TROUBLE CODE (PERMANENT DTC)
Permanent DTC is defined in SAE J1979/ISO 15031-5 Service $0A.
ECM stores a DTC issuing a command of turning on MIL as a permanent DTC and keeps storing the DTC as a permanent DTC until ECM judges that there is no presence of malfunction.
Permanent DTCs cannot be erased by using the Erase function of CONSULT-III or Generic Scan Tool (GST) and by disconnecting the battery to shut off power to ECM. This prevents a vehicle from passing the state emission inspection without repairing a malfunctioning part.
When not passing the state emission inspection due to more than one permanent DTC, permanent DTCs should be erased, referring to this manual.
NOTE:
- The important items in state emission inspection are that MIL is not ON, SRT test items are set, and permanent DTCs are not included.
- Permanent DTCs do not apply for regions that permanent DTCs are not regulated by law.
Permanent DTC Item
For permanent DTC items, MIL turns on. Testing and Inspection.
Permanent DTC Set Timing
The setting timing of permanent DTC is stored in ECM with the lighting of MIL when a DTC is confirmed.
Permanent DTC Service Procedure
How to Display Permanent DTC Status
WITH CONSULT-III
1. Turn ignition switch OFF and wait at 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at 10 seconds.
4. Turn ignition switch ON.
5. Select "PERMANENT DTC STATUS" in "DTC & SRT CONFIRMATION" mode with CONSULT-III.
NOTE:
Permanent DTCs stored in ECM memory are displayed on the CONSULT-III screen to show if a driving pattern required for erasing permanent DTCs is complete (CMPLT) or incomplete (INCMP).
CAUTION:
Since the "PERMANENT DTC STATUS" screen displays the previous trip information, repeat the following twice to update the information: "Ignition switch OFF", "Wait for more than 10 seconds" and "Ignition switch ON".
WITH GST
1. Turn ignition switch OFF and wait at 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at 10 seconds.
4. Turn ignition switch ON.
5. Select Service $0A with GST (Generic Scan Tool).
MALFUNCTION INDICATOR LAMP (MIL)
Description
The MIL is located on the combination meter.
1. The MIL will illuminate when the ignition switch is turned ON without the engine running. This is a bulb check.
If the MIL does not illuminate, check MIL circuit. Component Function Check.
2. When the engine is started, the MIL should go off.
If the MIL remains illuminating, the on board diagnostic system has detected an engine system malfunction.
On Board Diagnostic System Function
The on board diagnostic system has the following three functions.
Diagnostic Test Mode I -- Bulb Check
In this mode, the MIL on the instrument panel should stay ON. If it remains OFF, check the bulb. Component Function Check.
Diagnostic Test Mode I -- Malfunction Warning
This DTC number is clarified in Diagnostic Test Mode II (SELF-DIAGNOSTIC RESULTS)
Diagnostic Test Mode II -- Self-diagnostic Results
In this mode, the DTC and 1st trip DTC are indicated by the number of blinks of the MIL as shown below.
The DTC and 1st trip DTC are displayed at the same time. If the MIL does not illuminate in diagnostic test mode I (Malfunction warning), all displayed items are 1st trip DTCs. If only one code is displayed when the MIL illuminates in diagnostic test mode II (SELF-DIAGNOSTIC RESULTS), it is a DTC; if two or more codes are displayed, they may be either DTCs or 1st trip DTCs. DTC No. is same as that of 1st trip DTC. These unidentified codes can be identified by using the CONSULT-III or GST. A DTC will be used as an example for how to read a code.
A particular trouble code can be identified by the number of four-digit numeral flashes per the following.
The length of time the 1,000th-digit numeral flashes on and off is 1.2 seconds consisting of an ON (0.6-seconds) - OFF (0.6-seconds) cycle.
The 100th-digit numeral and lower digit numerals consist of a 0.3-seconds ON and 0.3-seconds OFF cycle.
A change from one digit numeral to another occurs at an interval of 1.0-second OFF. In other words, the later numeral appears on the display 1.3 seconds after the former numeral has disappeared.
A change from one trouble code to another occurs at an interval of 1.8-seconds OFF.
In this way, all the detected malfunctions are classified by their DTC numbers. The DTC 0000 refers to no malfunction. (See Testing and Inspection)
How to Switch Diagnostic Test Mode
NOTE:
- It is better to count the time accurately with a clock.
- It is impossible to switch the diagnostic mode when an accelerator pedal position sensor circuit has a malfunction.
- ECM always returns to Diagnostic Test Mode I after the ignition switch is turned OFF.
HOW TO SET DIAGNOSTIC TEST MODE II (SELF-DIAGNOSTIC RESULTS)
1. Confirm that accelerator pedal is fully released, turn ignition switch ON and wait 3 seconds.
2. Repeat the following procedure quickly five times within 5 seconds.
- Fully depress the accelerator pedal.
- Fully release the accelerator pedal.
3. Wait 7 seconds, fully depress the accelerator pedal and keep it depressed for approx. 10 seconds until the
MIL starts blinking.
NOTE:
Do not release the accelerator pedal for 10 seconds if MIL starts blinking during this period. This blinking is displaying SRT status and is continued for another 10 seconds.
4. Fully release the accelerator pedal.
ECM has entered to Diagnostic Test Mode II (Self-diagnostic results).
NOTE:
Wait until the same DTC (or 1st trip DTC) appears to completely confirm all DTCs.
HOW TO ERASE DIAGNOSTIC TEST MODE II (SELF-DIAGNOSTIC RESULTS)
1. Set ECM in Diagnostic Test Mode II (Self-diagnostic results). Refer to "How to Set Diagnostic Test Mode II
(Self-diagnostic Results)".
2. Fully depress the accelerator pedal and keep it depressed for more than 10 seconds.
The emission-related diagnostic information has been erased from the backup memory in the ECM.
3. Fully release the accelerator pedal, and confirm the DTC 0000 is displayed.
How to Erase Diagnostic Test Mode II (Self-diagnostic Results)
The DTC can be erased from the back up memory in the ECM by depressing accelerator pedal. Refer to "How to Erase Diagnostic Test Mode II (Self-diagnostic Results)".
- If the battery is disconnected, the DTC will be cleared from the backup memory within 24 hours.
- Be careful not to erase the stored memory before starting trouble diagnoses.
OBD SYSTEM OPERATION CHART
Relationship Between MIL, 1st Trip DTC, DTC, and Detectable Items
- When a malfunction is detected for the first time, the 1st trip DTC and the 1st trip freeze frame data are stored in the ECM memory.
- When the same malfunction is detected in two consecutive trips, the DTC and the freeze frame data are stored in the ECM memory, and the MIL will illuminate.
- The MIL will turn off after the vehicle is driven 3 times (driving pattern B) with no malfunction. A drive is counted only when the recorded driving pattern is met (as stored in the ECM). If another malfunction occurs while counting, the counter will reset.
- The DTC and the freeze frame data will be stored until the vehicle is driven 40 times (driving pattern A) without the same malfunction recurring (except for Misfire and Fuel Injection System). For Misfire and Fuel Injection System, the DTC and freeze frame data will be stored until the vehicle is driven 80 times (driving pattern
C) without the same malfunction recurring. The "TIME" in "SELF-DIAGNOSTIC RESULTS" mode of CONSULT-III will count the number of times the vehicle is driven.
- The 1st trip DTC is not displayed when the self-diagnosis results in OK for the 2nd trip.
Summary Chart
For details about patterns B and C under "Fuel Injection System" and "Misfire", see "EXPLANATION FOR
DRIVING PATTERNS FOR "MISFIRE [EXHAUST QUALITY DETERIORATION]", "FUEL INJECTION SYSTEM".
For details about patterns A and B under Other, see "EXPLANATION FOR DRIVING PATTERNS FOR "MISFIRE [EXHAUST QUALITY DETERIORATION]", "FUEL INJECTION SYSTEM".
*1: Clear timing is at the moment OK is detected.
*2: Clear timing is when the same malfunction is detected in the 2nd trip.
Relationship Between MIL, DTC, 1st Trip DTC and Driving Patterns for "Misfire [Exhaust Quality Deterioration]",
"Fuel Injection System"
Explanation for Driving Patterns for "Misfire [Exhaust Quality Deterioration]", "Fuel Injection System"
[Driving Pattern B]
Driving pattern B means the vehicle operation as per the following:
All components and systems should be monitored at least once by the OBD system.
- The B counter will be cleared when the malfunction is detected once regardless of the driving pattern.
- The B counter will be counted up when driving pattern B is satisfied without any malfunction.
- The MIL will turn off when the B counter reaches 3. (*2 in "OBD SYSTEM OPERATION CHART")
[Driving Pattern C]
Driving pattern C means operating vehicle as per the following:
The following conditions should be satisfied at the same time:
Engine speed: (Engine speed in the freeze frame data) �375 rpm
Calculated load value: (Calculated load value in the freeze frame data) x (1�0.1) [%]
Engine coolant temperature (T) condition:
- When the freeze frame data shows lower than 70�C (158�F), T should be lower than 70�C (158�F).
- When the freeze frame data shows higher than or equal to 70�C (158�F), T should be higher than or equal �C (158�F).
Example:
If the stored freeze frame data is as per the following:
Engine speed: 850 rpm, Calculated load value: 30%, Engine coolant temperature: 80�C (176�F)
To be satisfied with driving pattern C, the vehicle should run under the following conditions:
Engine speed: 475 - 1,225 rpm, Calculated load value: 27 - 33%, Engine coolant temperature: more than 70�C
(158�F)
- The C counter will be cleared when the malfunction is detected regardless of vehicle conditions above.
- The C counter will be counted up when vehicle conditions above are satisfied without the same malfunction.
- The DTC will not be displayed after C counter reaches 80.
- The 1st trip DTC will be cleared when C counter is counted once without the same malfunction after DTC is stored in ECM.
Relationship Between MIL, DTC, 1st Trip DTC and Driving Patterns Except For "Misfire [Exhaust Quality Deterioration]", "Fuel Injection System"
Explanation for Driving Patterns Except for "Misfire [Exhaust Quality Deterioration]", "Fuel Injection System"
[Driving Pattern A]
- The A counter will be cleared when the malfunction is detected regardless of (1) - (4).
- The A counter will be counted up when (1) - (4) are satisfied without the same malfunction.
- The DTC will not be displayed after the A counter reaches 40.
[Driving Pattern B]
Driving pattern B means operating vehicle as per the following:
All components and systems should be monitored at least once by the OBD system.
- The B counter will be cleared when the malfunction is detected once regardless of the driving pattern.
- The B counter will be counted up when driving pattern B is satisfied without any malfunctions.
- The MIL will turn off when the B counter reaches 3 (*2 in OBD SYSTEM OPERATION CHART).