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P1148

DTC P1148 CLOSED LOOP CONTROL

On Board Diagnosis Logic:






DTC Confirmation Procedure

CAUTION: Always drive vehicle at a safe speed.

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.

TESTING CONDITION:
- Never raise engine speed above 3,200 rpm during the "DTC Confirmation Procedure". If the engine speed limit is exceeded, retry the procedure from step 4.
- Before performing the following procedure, confirm that battery voltage is more than 11 V at idle.




With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select "DATA MONITOR" mode with CONSULT-II.
3. Hold engine speed at 2,000 rpm and check the following.
- "HO(2)S(1) (B1)" voltage should go above 0.70 V at least once.
- "HO(2)S(1) (B1)" voltage should go below 0.21 V at least once.
If the result is NG, perform "Diagnosis Procedure". If the result is OK, perform the following step.
4. Let engine idle at least 4 minutes.




5. Maintain the following condition at least 50 consecutive seconds.
During this test, P0130 DTC may be displayed on CONSULT-II screen.
6. If DTC is detected, go to "Diagnostic Procedure".

Overall Function Check
Use this procedure to check the overall function of the closed loop control. During this check, a DTC might not be confirmed.




With GST
1. Start engine and warm it up to normal operating temperature.
2. Set voltmeter probes between ECM terminal 62 [Heated oxygen sensor 1 (front) signal] and engine ground.
3. Check the following with engine speed held at 2,000 rpm constant under no load.
- The voltage should go above 0.70 V at least once.
- The voltage should go below 0.21 V at least once.
4. If NG, go to "Diagnostic Procedure".

Step 1 - 4:




Step 5:




Step 6 - 10:




Step 11 - 12:




Diagnostic Procedure