P0430
P0420, P0430 THREE WAY CATALYST FUNCTION
DTC Logic
DTC DETECTION LOGIC
The ECM monitors the switching frequency ratio of air fuel ratio (A/F) sensor 1 and heated oxygen sensor 2.
A three way catalyst 1 with high oxygen storage capacity will indicate a low switching frequency of heated oxygen sensor 2. As oxygen storage capacity decreases, the heated oxygen sensor 2 switching frequency will increase.
When the frequency ratio of A/F sensor 1 and heated oxygen sensor 2 approaches a specified limit value, the three way catalyst 1 malfunction is diagnosed.
DTC CONFIRMATION PROCEDURE
1.INSPECTION START
Do you have CONSULT-III?
Do you have CONSULT-III?
YES - GO TO 2.
NO - GO TO 7.
2.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Do not hold engine speed for more than the specified minutes below.
- GO TO 3.
3.PERFORM DTC CONFIRMATION PROCEDURE-I
With CONSULT-III
1. Turn ignition switch ON and select "DATA MONITOR" mode with CONSULT-III.
2. Start engine and warm it up to the normal operating temperature.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON.
5. Turn ignition switch OFF and wait at least 10 seconds.
6. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
7. Let engine idle for 1 minute.
8. Make sure that "COOLAN TEMP/S" indicates more than 70�C (158�F).
If not, warm up engine and go to next step when "COOLAN TEMP/S" indication reaches 70�C (158�F).
9. Open engine hood.
10. Select "DTC & SRT CONFIRMATION" then "SRT WORK SUPPORT" mode with CONSULT-III.
11. Rev engine up to about 2,000 rpm and hold it for 3 consecutive minutes then release the accelerator pedal completely.
12. Check the indication of "CATALYST".
Which is displayed on CONSULT-III screen?
CMPLT - GO TO 6.
INCMP - GO TO 4.
4.PERFORM DTC CONFIRMATION PROCEDURE-II
1. Wait 5 seconds at idle.
2. Rev engine up to about 2,000 rpm and maintain it until "INCMP" of "CATALYST" changes to "CMPLT" (It will take approximately 5 minutes).
Does the indication change to "CMPLT"?
YES - GO TO 6.
NO - GO TO 5.
5.PERFORM DTC CONFIRMATION PROCEDURE AGAIN
1. Stop engine and cool it down to less than 70�C (158�F).
2. Perform DTC CONFIRMATION PROCEDURE again.
- GO TO 3.
6.PERFORM DTC CONFIRMATION PROCEDURE-III
Check 1st trip DTC.
Is 1st trip DTC detected?
YES - Go to SEE Diagnosis Procedure.
NO - INSPECTION END
7.PERFORM COMPONENT FUNCTION CHECK
Perform component function check. SEE Component Function Check.
NOTE:
Use component function check to check the overall function of the three way catalyst (manifold). During this check, a 1st trip DTC might not be confirmed.
Is the inspection result normal?
YES - INSPECTION END
NO - Go to SEE Diagnosis Procedure.
Component Function Check
1.PERFORM COMPONENT FUNCTION CHECK
Without CONSULT-III
1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
4. Let engine idle for 1 minute.
5. Open engine hood.
6. Check the voltage between ECM harness connector terminals under the following condition.
Is the inspection result normal?
YES - INSPECTION END
NO - Go to SEE Diagnosis Procedure.
Diagnosis Procedure
1.CHECK EXHAUST SYSTEM
Visually check exhaust tubes and muffler for dents.
Is the inspection result normal?
YES - GO TO 2.
NO - Repair or replace.
2.CHECK EXHAUST GAS LEAK
1. Start engine and run it at idle.
2. Listen for an exhaust gas leak before the three way catalyst 1.
Is exhaust gas leak detected?
YES - Repair or replace.
NO - GO TO 3.
3.CHECK INTAKE AIR LEAK
Listen for an intake air leak after the mass air flow sensor.
Is intake air leak detected?
YES - Repair or replace.
NO - GO TO 4.
4.CHECK IDLE SPEED AND IGNITION TIMING
For procedure, Basic Inspection.
For specification, [1][2]Idle Speed and [1][2]Ignition Timing.
Is the inspection result normal?
YES - GO TO 5.
NO - Follow the Basic Inspection.
5.CHECK FUEL INJECTORS
1. Stop engine and then turn ignition switch ON.
2. Check the voltage between ECM harness connector terminals as per the following.
Is the inspection result normal?
YES - GO TO 6.
NO - Perform Testing and Inspection.
6.CHECK FUNCTION OF IGNITION COIL-I
CAUTION:
Perform the following procedure in a place where with no combustible objects and good ventilation.
1. Turn ignition switch OFF.
2. Remove fuel pump fuse (1) in IPDM E/R (2) to release fuel pressure.
NOTE:
Do not use CONSULT-III to release fuel pressure, or fuel pressure applies again during the following procedure.
3. Start engine.
4. After engine stalls, crank it two or three times to release all fuel pressure.
5. Turn ignition switch OFF.
6. Remove all ignition coil harness connectors to avoid the electrical discharge from the ignition coils.
7. Remove ignition coil and spark plug of the cylinder to be checked.
8. Crank engine for 5 seconds or more to remove combustion gas in the cylinder.
9. Connect spark plug and harness connector to ignition coil.
10. Fix ignition coil using a rope etc. with gap of 13 - 17 mm (0.52 - 0.66 in) between the edge of the spark plug and grounded metal portion as shown in the figure.
11. Crank engine for about 3 seconds, and check whether spark is generated between the spark plug and the grounded metal portion.
Spark should be generated.
CAUTION:
- During the operation, always stay 0.5 m (1.6 ft) or more away from the spark plug and ignition coil. Be careful not to get an electrical shock while checking, because the electrical discharge voltage becomes 20 kV or more.
- It might damage the ignition coil if the gap of more than 17 mm (0.66 in) is made.
NOTE:
When the gap is less than 13 mm (0.52 in), a spark might be generated even if the coil is malfunctioning.
Is the inspection result normal?
YES - GO TO 10.
NO - GO TO 7.
7.CHECK FUNCTION OF IGNITION COIL-II
1. Turn ignition switch OFF.
2. Disconnect spark plug and connect a non-malfunctioning spark plug.
3. Crank engine for about 3 seconds, and recheck whether spark is generated between the spark plug and the grounded metal portion.
Spark should be generated.
Is the inspection result normal?
YES - GO TO 8.
NO - Check ignition coil, power transistor and their circuits. Ignition Signal.
8.CHECK SPARK PLUG
Check the initial spark plug for fouling, etc.
Is the inspection result normal?
YES - Replace spark plug(s) with standard type one(s). For spark plug type, Inspection.
NO - Repair or clean spark plug. Then GO TO 9.
9.CHECK FUNCTION OF IGNITION COIL-III
1. Reconnect the initial spark plugs.
2. Crank engine for about three seconds, and recheck whether spark is generated between the spark plug and the grounded portion.
Spark should be generated.
Is the inspection result normal?
YES - INSPECTION END
NO - Replace spark plug(s) with standard type one(s). For spark plug type, Removal And Installation.
10.CHECK FUEL INJECTOR
1. Turn ignition switch OFF.
2. Remove fuel injector assembly. Removal And Installation.
Keep fuel hose and all fuel injectors connected to fuel tube.
3. Disconnect all ignition coil harness connectors.
4. Reconnect all fuel injector harness connectors disconnected.
5. Turn ignition switch ON.
6. Check that fuel does not drip from fuel injector.
Does fuel drip from fuel injector?
YES - Replace the fuel injector(s) from which fuel is dripping. Removal And Installation.
NO - GO TO 11.
11.CHECK INTERMITTENT INCIDENT
Intermittent Incident.
Is the inspection result normal?
YES - Replace three way catalyst assembly. Exploded View.
NO - Repair or replace harness or connector.