Suzuki SY413 Service Manual page 2767

6-2-50 ENGINE GENERAL INFORMATION AND DIAGNOSIS (J18 ENGINE WITH WU TWC)
TROUBLESHOOTING (DTC P0121)
STEP
1 Was "ENGINE DIAG. FLOW TABLE" performed?
2 Check TP Sensor and Its Circuit.
1) Turn ignition switch OFF and connect SUZUKI scan tool to
DLC.
2) Turn ignition switch ON and check TP sensor output volt-
age when throttle valve is at idle position and fully opened.
See Fig. 1.
Dose voltage vary within specified value linearly as shown in
figure?
3 Check TP Sensor.
1) Turn ignition switch OFF.
2) Disconnect TP sensor connector.
3) Check for proper connection to TP sensor at each terminal.
4) If OK, then measure resistance between terminals of dicon-
nected ECM connector and check if each measured value
is as specified below.
See Fig. 2.
Between C20-25 and C20-27: 4.0 – 6.0 kW
Between C20-18 and C20-27: 100 W – 6.5 kW, varying
Are measured values as specified?
Fig.1 for Step 2
ACTION
according to throttle valve
opening.
Fig.2 for Step 3
YES
Go to Step 2. Go to "ENGINE
DIAG. FLOW
TABLE".
If voltmeter was Go to Step 3.
used, check termi-
nal C20-25 for
poor connection.
If OK, substitute a
known-good ECM
and recheck.
High resistance in Replace TP sen-
"P/G", "Gr" or "Or" sor.
circuit.
If wire and con-
nection are OK,
substitute a
known-good ECM
and recheck.
NO