Detecting Condition

DETECTING CONDITION

HINT: Diagnostic trouble code "21" is for the main heated oxygen sensor (Fr) circuit. Diagnostic trouble code "28" is for the main heated oxygen sensor (Rr) circuit.

DIAGNOSTIC TROUBLE CODE DETECTION DRIVING PATTERN




Main Heated Oxygen Sensor Deterioration
The purpose of the driving pattern to simulate diagnostic trouble code detecting condition after diagnostic trouble code is recorded and to check that the malfunction is corrected when the repair is completed confirming that diagnostic trouble code is no longer detected.

It is vital that this test routine is adhered to detect the malfunction.
1. Disconnect the EFI fuse (20 A) for 10 sec. or more, with IG switched OFF. Initiate test mode (Connect terminal TE2 and E1 of data link connector 1 or 2 with IG switched OFF).
2. Start the engine and warm it up with all accessories switches OFF.
3. Let the engine idle for 3 min.
4. Accelerate gradually with in the range 1,300 - 1,700 rpm (centered around 1,500 rpm) with the A/C switch ON and D position for A/T.

HINT:
- Ensure engine rpm does not fall below 1,200 rpm.
- Gradually depress the accelerator pedal at a suitable rate to comply with the test requirements on the above graph.
- Never allow engine rpm to drop at any time during the test.

5. Maintain the vehicle speed at 64 - 80 km/h (40 - 50 mph).
6. Keep the vehicle running for 1 - 2 min. after starting acceleration.

HINT: If a malfunction exists, the Malfunction Indicator Lamp will light up after approx. 60 sec. from the start of acceleration.

NOTICE: If the conditions in this test are not strictly followed, detection of the malfunction will not be possible.




WIRING DIAGRAM