ENGINE GENERAL INFORMATION AND DIAGNOSIS (M13 ENGINE) 6-2-131
Troubleshooting
Step Action Yes No
1Was “Engine and Emission Control System
Check” performed?
Go to Step 2. Go to “Engine and Emis-
sion Control System
Check”.
2 Check vehicle speed signal.
Is vehicle speed displayed on scan tool in step
4) and 5) of DTC confirmation procedure?
Intermittent trouble or
faulty ECM.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection” in Section 0A.
Go to Step 3.
3 Check power supply circuit.
1) With ignition switch turned OFF, disconnect
connector from VSS.
2) Check for proper connection for “BLK/RED”,
“BRN” and “YEL” wire terminal.
3) If wires are OK, turn ON ignition switch,
measure voltage between engine ground
and “BLK/RED” wire terminal.
Is it voltage 10 – 14 V?
Go to Step 4. “BLK/WHT” wire open cir-
cuit.
4 Check ground circuit.
1) Measure resistance between engine body
ground and “BRN” wire terminal with ignition
switch turn OFF.
Is resistance below 5
Ω
?
Go to Step 5. “BRN” wire open or high
resistance circuit.
5 Check wire circuit.
1) Turn ON ignition switch, measure voltage
between engine ground and “YEL” wire ter-
minal at VSS connector. See Fig. 1.
Is it voltage 4 – 5 V?
Go to Step 9. Go to Step 6.
6 Check ECM voltage.
1) Turn ON ignition switch, measure voltage
between vehicle body ground and “E22-19”
terminal at ECM connector.
Is it voltage 4 – 5 V?
“YEL” wire open circuit. Go to Step 7.
7 Check short circuit.
1) Disconnect connectors from ECM with igni-
tion switch turned OFF.
2) Turn ON ignition switch, measure voltage
between engine ground and “E22-19” termi-
nal.
Is it voltage 0 V?
Go to Step 8. “YEL” wire shorted to
power supply circuit.
8 Check short circuit.
1) Measure resistance between engine ground
and “E22-19” terminal with ignition switch
turned OFF.
Is resistance infinity?
Go to Step 9. “YEL” wire shorted to
ground circuit.
If wire are OK, substitute a
known-good ECM and
recheck.