P0430
DTC P0430 THREE WAY CATALYST FUNCTIONOn Board Diagnosis Logic
The ECM monitors the switching frequency ratio of heated oxygen sensors 1 and 2.
A three way catalyst (manifold) 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 heated oxygen sensors 1 and 2 approaches a specified limit value, the three way catalyst (manifold) malfunction is diagnosed.
DTC Confirmation Procedure
NOTE: If "DTC Confirmation Procedure" has been previously conducted, always turn ignition switch "OFF" and wait at least 10 seconds before conducting the next test.
WITH CONSULT-II
TESTING CONDITION:
Do not hold engine speed for more than the specified minutes below.
1. Turn ignition switch "ON" and select "DATA MONITOR" mode with CONSULT-II.
2. Start engine and warm it up to the normal operating temperature.
3. Turn ignition switch "OFF" and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least one minute under no load.
5. Let engine idle for one minutes.
6. 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 to 70 °C (158 °F).
7. Open engine hood.
8. Select "DTC & SRT CONFIRMATION" then "SRT WORK SUPPORT" mode with CONSULT-II.
9. Rev engine up to 2,000 to 3,000 rpm and hold it for 3 consecutive minutes then release the accelerator pedal completely. If "INCMP" of "CATALYST" changed to "CMPLT", go to step 12.
10. Wait 5 seconds at idle.
11. Rev engine up to 2,000 to 3,000 rpm and maintain it until "INCMP" of "CATALYST" changes to "CMPLT" (It will take approximately 5 minutes).
If not "CMPLT", stop engine and cool it down to less than 70 °C (158 °F) and then retest from step 1.
12. Select "SELF-DIAG RESULTS" mode with CONSULT-II.
13. Confirm that the 1st trip DTC is not detected.
If the 1st trip DTC is detected, go to "Diagnostic Procedure" below.
Overall Function Check
Use this procedure to check the overall function of the three way catalyst (manifold). During this check, a DTC might not be confirmed.
WITH GST
1. Turn ignition switch "OFF" and wait at least 10 seconds.
2. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least one minute under no load.
3. Let engine idle for one minutes.
4. Open engine hood.
5. Set voltmeters probes between ECM terminals 35 [HO2S1 (bank 1) signal], 16 [HO2S1 (bank 2) signal] and engine ground, and ECM terminals 74 [HO2S2 (bank 1) signal], 55 [HO2S2 (bank 2) signal] and engine ground.
6. Keep engine speed at 2,000 rpm constant under no load.
7. Make sure that the voltage switching frequency (high & low) between ECM terminals 74 and engine ground, or 55 and engine ground is very less than that of ECM terminals 35 and engine ground, or 16 and engine ground.
Switching frequency ratio = A/B
A: Heated oxygen sensor 2 voltage switching frequency
B: Heated oxygen sensor 1 voltage switching frequency This ratio should be less than 0.75.
If the ratio is greater than above, it means three way catalyst (manifold) does not operate properly. Go to "Diagnostic Procedure" below.
NOTE: If the voltage at terminal 35 or 16 does not switch periodically more than 5 times within 10 seconds at step 7, perform trouble diagnosis for "DTC P0133, P0153" first.
Diagnostic Procedure
Diagnostic Procedure Step 1 - 3:
Diagnostic Procedure Step 4 - 6:
