Suzuki WagonR+ RB310 Service Manual page 2433

6-74 ENGINE DIAGNOSIS
DTC P0325 (DTC No.17) KNOCK SENSOR CIRCUIT MALFUNCTION
CIRCUIT DESCRIPTION
DTC DETECTING CONDITION
D KNOCK: 3.75 V or more
D KNOCK: 1.25 V or less
DTC CONFIRMATION PROCEDURE
1) Clear DTC, start engine and keep it at idle for 1 min.
2) Select "DTC" mode on scan tool and check DTC.
INSPECTION
STEP
1 Was "ENGINE DIAG. FLOW TABLE performed?
2 1) With engine running, check voltage from
"E21-12" terminal of ECM connector to body
ground. See Fig. 1.
2) Is voltage about 1.25 – 3.75 V?
3 1) Stop engine.
2) With ignition switch at OFF position, disconnect
knock sensor connector.
3) With ignition switch at ON position, check
voltage from "W" to body ground terminal of
knock sensor connector. See Fig. 2.
4) Is it 4 – 5 V?
E21-25
E21-12
ACTION
To other sensor
POSSIBLE CAUSE
D "W" circuit open or shorted to ground
D KNOCK sensor malfunction
D ECM malfunction
YES
Go to Step 2.
Knock sensor and its
circuit are in good
condition.
Intermittent trouble or
faulty ECM.
Recheck, referring to
INTERMITTENT
TROUBLE in
Section 0A.
Faulty knock sensor.
Substitute a known-
good knock sensor and
recheck.
NO
Go to "ENGINE
DIAG. FLOW TABLE".
Go to Step 3.
"W" wire open, shorted
to ground circuit or poor
"E21-12" connection.
If wire and connection
are OK, substitute a
known-good ECM and
recheck.