Toyota T100 1996 Service Manual page 502

DI−238
4 Check for open and short in harness and connector in IGT1 − 3 signal circuit be-
tween ECM and igniter (See page IN−26).
OK
5 Check voltage between terminals IGT1 − 3 of ECM connector and body ground.
START
IGT1 (+) IGT2 (+) IGT3 (+)
For M/T
IGT3 (+) IGT2 (+)
For A/T
BE6653
P24328
P24327
IGT1 ∼ 3 and IGF Signal Waveform
VOLT
5
0
5
0
5
0
5
0
20 msec./Division (Idling)
OK
1996 TOYOTA T100 (RM449U)
DIAGNOSTICS
NG
PREPARATION:
Remove the right cowl side trim (See page SF−61).
CHECK:
Measure voltage between terminal IGT1 − 3 of ECM connector
and body ground when engine is cranked.
OK:
IGT1 (+)
A00123
Reference INSPECTION USING OSCILLOSCOPE
During idling, check waveform between terminals IGT1 − 3, IGF
and E1 of ECM.
IGT1
HINT:
The correct waveforms are as shown.
IGT2
IGT3
IGF
P20870
NG
− ENGINE (5VZ−FE)
Repair or replace harness or connector.
Voltage: More than 0.1 V and less than 4.5 V
Check and replace ECM (See page IN−26).