Toyota T100 1996 Service Manual page 313

3 Check output voltage of heated oxygen sensor during idling.
PREPARATION:
Warm up the heated oxygen sensor with the engine at 2,500 rpm for approx. 90 sec.
CHECK:
Use the OBD II scan tool or TOYOTA hand−held tester read the output voltage of the heated oxygen sensor
during idling.
OK:
Heated oxygen sensor output voltage:
Alternates repeatedly between less than 0.4 V and more than 0.55 V (See the following table)
NG
Replace heated oxygen sensor.
1996 TOYOTA T100 (RM449U)
DIAGNOSTICS − ENGINE (3RZ−FE)
OK Perform confirmation driving pattern.
DI−49
P18349