With CONSULT

OVERALL FUNCTION CHECK
Instead of performing DTC DETECTING CONDITION, the following method can be used for checking the three way catalyst function. (The "NG" of the OVERALL FUNCTION CHECK means the same as the DTC detection.)
1. Start engine and warm it up sufficiently.




2. Set "MANU TRIG" and "HI SPEED", then select "FR O2 SENSOR", "RR O2 SENSOR", "FR O2 MNTR", "RR O2 MNTR" in "DATA MONITOR" mode with CONSULT.
3. Touch "RECORD" on CONSULT screen with engine speed held at 2,000 rpm constant under no load.
4. Make sure that the switching frequency between "RICH" and "LEAN" of "RR O2 SENSOR" is very less than that of "FR O2 SENSOR".

Switching frequency ratio=
Rear heated oxygen sensor switching frequency -over-
Front oxygen sensor switching frequency

This ratio should be less than 0.8.

If the ratio is greater than 0.8, the three way catalyst is not operating properly.