ECM SUZUKI SWIFT 2000 1.G SF310 Service Repair Manual

Oscilloscope Waveforms
Crankshaft
timing belt pulleyCKP
sensor
2V/Div.
5ms/Div.
Waveforms at specified idle speed
6-72 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
DTC P0335 CRANKSHAFT POSITION (CKP) SENSOR CIRCUIT MALFUNCTION
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE

No CKP sensor signal during 1 revolution of
camshaft.
CKP sensor circuit open or short.

Crankshaft timing belt pulley teeth damaged.

CKP sensor malfunction, foreign material being
attached or improper installation.

ECM (PCM) malfunction.
Reference
Connect oscilloscope between terminals C01-3 (+) and C01-11 (–) of ECM (PCM) connector connected to ECM
(PCM) and check CKP sensor signal.
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.

ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-73
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE DIAG.
FLOW TABLE”.
2Check CKP Sensor for Resistance.
1) Disconnect CKP sensor connector with ignition
switch OFF.
2) Then check for proper connection to CKP sensor
at “W/B” and “W/R” wire terminals.
3) If OK, measure sensor resistance between
terminals. See Fig. 1.
CKP sensor resistance: 360 – 460 Ω
at 20C, (68F)
4) Measure resistance between each terminal and
ground.
Insulation resistance: 1 MΩ or more.
Were measured resistance valves in step 3) and 4)
as specified?Go to Step 3.Replace CKP sensor.
3Check visually CKP sensor and pulley for the
following. See Fig. 2.

Damage

No foreign material attached.

Correct installation.
Are they in good condition?“W/B” or “W/R” wire
open or shorted to
ground, or poor
connection at C01-3
or C01-11.
If wire and connection
are OK, intermittent
trouble or faulty ECM
(PCM).
Recheck for
intermittent referring
to “Intermittent and
Poor Connection” in
Section 0A.Clean, repair or
replace.
Fig. 1 for Step 2 Fig. 2 for Step 3

Display of fuel injection signal using oscilloscope
1. CMP sensor signal
2. Fuel injector signal
3. Fuel injection time
2V/Div.
20V/Div.1
2
10ms/Div
Waveforms at specified idle speed 3 Sensor rotor
in distributorCamshaft
position sensor
6-74 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
DTC P0340 CAMSHAFT POSITION (CMP) SENSOR CIRCUIT MALFUNCTION
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE

No CMP sensor signal for 2 seconds at engine
cranking (CKP sensor signal is inputted).
CMP sensor circuit open or short.

Signal rotor teeth damaged.

CMP sensor malfunction, foreign material being
attached or improper installation.

ECM (PCM) malfunction.
Reference
Connect oscilloscope between terminals C01-2 and C01-10 of ECM (PCM) connector connected to ECM (PCM)
and check CMP sensor signal.
DTC CONFIRMATION PROCEDURE
1) Clear DTC.
2) Start engine and keep it at idle for 1 min.
3) Select “DTC” mode on scan tool and check DTC.

ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-75
Fig. 1 for Step 3 Fig. 2 for Step 5
“a”: Air gap
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE DIAG.
FLOW TABLE”.
2Is DTC P1500 (Engine starter signal circuit
malfunction) detected?Go to DTC P1500
Diag. Flow Table.Go to Step 3.
3Check CMP Sensor for Resistance.
1) Measure resistance of CMP sensor by referring to
“CMP SENSOR (PICK UP COIL) RESISTANCE”
in SECTION 6F.
Is resistance within specified value?Go to Step 4.Faulty CMP sensor.
4Check Wire Harness.
1) With ignition switch at OFF position, disconnect
ECM (PCM) electrical connectors.
2) Measure resistance from terminal “C01-2” to
“C01-10” of ECM (PCM) connector. See Fig. 1.
Is resistance within 185 – 275 Ω at 20C (68F)?Go to Step 5.“W” or “Or” wire open
or short.
Poor connection of
CMP sensor
connector terminal.
5Check Air Gap Between Rotor Tooth and Sensor. See
Fig. 2.
1) Remove Distributor cap.
2) Visually inspect CMP sensor signal rotor for
damage.
3) Measure air gap by referring “SIGNAL ROTOR
AIR GAP” in Section 6F.
Was any damage found?Faulty CMP sensor
signal rotor.Poor connection of
ECM (PCM)
connector terminal.
If OK, substitute a
known-good ECM
(PCM) and recheck
CMP.

6-76 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
Oscilloscope Waveforms
Engine running at
Closed loop conditionFuel
CutIdle after fuel cut 0.5 V / Div
2 sec. / Div Heated
oxygen
sensor-1
Warm up three way
catalytic converter (if equipped)
Three way catalytic converterTo other sensor
To other
sensors
Heated oxygen sensor-2
G
DTC P0420 CATALYST SYSTEM EFFICIENCY BELOW THRESHOLD
CIRCUIT DESCRIPTION
ECM (PCM) monitors oxygen concentration in the exhaust gas which has passed the three way catalytic converter
by HO2S-2.
When the catalyst is functioning properly, the variation cycle of HO2S-2 output voltage (oxygen concentration) is
slower than that of HO2S-1 output voltage because of the amount of oxygen in the exhaust gas which has been
stored in the catalyst.
Reference
DTC DETECTING CONDITIONPOSSIBLE CAUSE

While vehicle running at constant speed under other
than high load.

Time from rich or lean switching command is output
till HO2S-2 output voltage crosses 0.45 V is less than
specified value.
2 driving cycle detection logic, monitoring once / 1
driving.
Exhaust gas leak

Three way catalytic converter malfunction

Fuel system malfunction

HO2S-2 malfunction

HO2S-1 malfunction

6-80 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
Fig. 1 for Step 1
Main
fuseIgnition switch“IG COIL METER”
Radiator fan
relay
Radiator fan motor
DTC P0480 RADIATOR FAN CONTROL SYSTEM MALFUNCTION
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE

Low voltage at terminal C02-20 when engine coolant
temp. is below 91C, 195F.
2 driving cycle detection logic, continuous monitoring.
“B/W” or “BI” circuit open or short

Radiator fan relay malfunction

ECM (PCM) malfunction
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON.
3) Warm up engine until radiator cooling fan starts to operate.
4) Check pending DTC in “ON BOARD TEST” or “PENDING DTC” mode and DTC in “DTC” mode.

ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-81
Fig. 1 for Step 2 Fig. 2 for Step 3
1. Radiator fan relay
2. Relay box
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE DIAG.
FLOW TABLE”.
2Check Radiator Cooling Fan Relay and Its Circuit.
1) Turn ignition switch ON.
2) Check for voltage at terminal C02-20 of ECM
(PCM) connector connected, under following
condition. See Fig. 1.
When engine coolant temp. is lower than
96C, 205F and A / C switch turns OFF:
10 – 14 V
Is voltage as specified?Intermittent trouble or
faulty ECM (PCM).
Check for intermittent
referring to “Intermittent
and Poor Connection”
in Section 0A.Go to Step 3.
3Check Radiator Fan Control Relay.
1) Turn ignition switch OFF and remove radiator
fan relay.
2) Check for proper connection to the relay at
“B/W” and “Bl” wire terminals.
3) If OK, then measure resistance between
terminals a and b. See Fig. 2.
Is it 100 – 120 Ω?“B/W” or “Bl” circuit
open or short.
If wires and connections
are OK, substitute a
known-good ECM (PCM)
and recheck.Replace radiator fan
relay.

6-82 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
Vehicle speed
sensor in
combination meterC03-2
C03-2
DTC P0500 VEHICLE SPEED SENSOR (VSS) MALFUNCTION (M / T)
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE

VSS signal not inputted while vehicle running in “D”
range or during fuel cut at deceleration.
2 driving cycle detection logic, continuous monitoring
“B/Bl” circuit open

“Y/G” circuit open or short

VSS malfunction

ECM malfunction

Speedometer cable malfunction
DTC CONFIRMATION PROCEDURE
WARNING:

When performing a road test, select a place where there is no traffic or possibility of a traffic accident
and be very careful during testing to avoid occurrence of an accident.

Road test should be carried out with 2 persons, a driver and a tester.
1) Clear DTC and warm up engine to normal operating temperature.
2) Increase vehicle speed to 50 mph, 80 km / h in 3rd gear or “2” range while observing vehicle speed displayed
on scan tool.
3) Release accelerator pedal and with engine brake applied, keep vehicle coasting (fuel cut condition) for 4 sec.
or more.
4) Check pending DTC and DTC.

ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-83
Fig. 1 for Step 3 Fig. 2 for Step 4
C03-2
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE DIAG.
FLOW TABLE”.
2Does speedometer indicate vehicle speed?Go to Step 3.Speedometer cable
disconnected or
broken.
3Check VSS and Its Circuit.
1) Disconnect ECM connector with ignition
switch OFF.
2) Check for proper connection to ECM at
terminal C03-2.
3) If OK, then connect ohmmeter between
terminal C03-2 of ECM connector and body
ground. See Fig. 1.
4) Hoist front end of vehicle and lock front right
tire.
5) Turn front left tire slowly.
Does ohmmeter indicator deflect between
0 and ∞ a few times while tire is turned one
revolution?Intermittent trouble or
faulty ECM.
Check for intermittent
referring to “Intermittent
and Poor Connection”
in Section 0A.Go to Step 4.
4Check VSS.
1) Remove combination meter.
2) Connect ohmmeter between “VSS” terminal
(No.10) and “GND” (No.4) terminal of
combination meter and turn cable joint of
speedometer with a screwdriver. Ohmmeter
indicator should move back and forth between
0 (zero) and ∞ (infinity) 4 times while cable joint
is turned one full revolution. See Fig. 2.
Is it in good condition?“Y / G” or “B / Bl” wire
open or short, or poor
connector connection.Replace VSS.

Main
fuseMain relay
Idle speed
control relay
To TP sensor
Idle speed control actuator
6-86 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
DTC P0505 IDLE CONTROL SYSTEM MALFUNCTION
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE
DTC will set when A, B or C condition is met.
A: Throttle opening change is small as compared with
electrically live time.
B: Throttle valve opening is not within its target range
with CTP switch ON.
C: Drive voltage exists though ECM (PCM) is not
outputting ISC drive command.
Malajusted accelerater cable

Poor movement of throttle valve

Closed throttle position switch malfunction

Idle speed control actuator malfunction

Idle speed control relay malfunction

“Gr / B”, “Gr / Y”, “Gr”, “Gr / R”, “Gr / G”, “Lg” or “B/Bl”
circuit open or short

Throttle position sensor malfunction

ECM (PCM) malfunction
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON.
3) Start cold engine.
4) Run it idle for 5 min.
5) Select “DTC” mode on scan tool and check DTC.
NOTE:
If engine speed changes up and down when engine speed is increased by opening throttle valve more
than half but not changing its opening, it is possible that closed throttle position switch is malfunction-
ing.