2000 SUZUKI SWIFT engine

ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-81
Oscilloscope WaveformsHeated
oxygen
sensor-1To other sensor
Heated oxygen
sensor-2
Warm up three way
catalytic converterThree way catalytic converter
Engine running at
Closed loop conditionFuel
CutIdle after fuel cut 0.5 V / Div
2 sec. / Div
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

6-1-82 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
1) 2) 3) 4) 41 – 46 mph
(65 – 75 km / h)
28 – 34 mph
(45 – 55 km / h)
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 tester, on a level road.
1) Turn ignition switch OFF.
Clear DTC with ignition switch ON, check vehicle and environmental condition for:
–Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)
–Intake air temp.: between –10C and 80C (14F and 158F)
–Engine coolant temp.: 70C, 230F or higher
2) Start engine and drive vehicle at 41 – 46 mph, 65 – 75 km / h for 8 min. or longer.
While this driving, if “Catalyst Monitoring TEST COMPLETED” is displayed in “READINESS TESTS” mode and
DTC is not displayed in “DTC” mode, confirmation test is completed.
If “TEST NOT COMPLTD” is still being displayed, continue test driving.
3) Decrease vehicle speed at 28 – 34 mph, 45 – 55 km / h, and hold throttle valve at that opening position for 2 min.
and confirm that short term fuel trim vary within –20% –+20% range.
4) Stop vehicle (do not turn ignition switch OFF) and confirm test results according to following “Test Result Con-
firmation Flow Table”.
Test Result Confirmation Flow Table
STEPACTIONYESNO
1Check DTC in “DTC” mode and pending DTC in
“ON BOARD TEST” or “PENDING DTC” mode.
Is DTC or pending DTC displayed?Proceed to applicable
DTC Diag. Flow Table.Go to Step 2.
2Set scan tool to “READINESS TESTS” mode and
check if testing has been completed.
Is test completed?No DTC is detected
(confirmation test is
completed).Repeat DTC
confirmation
procedure.

ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-83
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE DIAG.
FLOW TABLE”.
2Check Short Term Fuel Trim.
Did short term fuel trim vary within –20% –+20%
range in step 3) of DTC confirmation test?Go to Step 3.Check fuel system.
Go to DTC P0171 / P0172
Diag. Flow Table.
3Check HO2S-2 for Output Voltage.
Perform steps 1) through 9) of DTC confirmation
procedure for DTC P0136 (HO2S-2 malfunction)
and check output voltage of HO2S-2 then.
Is over 0.6 V and below 0.3 V indicated?Replace three way
catalytic converter.Check “R” and “G” wires
for open and short, and
connections for poor
connection.
If wires and connections
are OK, replace
HO2S-2.

6-1-84 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
1. EVAP canister purge valve
2. To main relay
3. ECM (PCM)
4. Sensed information
5. Intake manifold
6. EVAP canister
7. Tank pressure control valve
8. Fuel vapor line
9. Fuel tank
Fig. 1 for Step 1
DTC P0443 EVAP PURGE CONTROL VALVE CIRCUIT MALFUNCTION
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE
Canister Purge control valve circuit is opened
or shorted.
“V/R” circuit open or short

“R/B” circuit open

Canister purge valve malfunction
DTC CONFIRMATION PROCEDURE
1) Clear DTC with ignition switch ON.
2) Select “DTC” mode on scan tool and check DTC.
INSPECTION
STEPACTIONYESNO
1Check EVAP canister purge valve operation
1) With ignition switch OFF, disconnect coupler
from canister purge valve.
2) Check resistance of EVAP canister purge
valve.
Resistance between
two terminals : 30 – 34 Ω at 20C (68F)
Resistance between
terminal and body : 1M Ω or higher
Is it as specified?“V/R” circuit open or
short.Replace EVAP canister
purge valve.

Radiator cooling fan relay
To
ECM
Main
relay
Relay
box
“RDTR”
(Radiator fan)Radiator cooling
Fan motor
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-85
DTC P0480 RADIATOR COOLING FAN CONTROL SYSTEM MALFUNCTION
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE

Low voltage at terminal C02-18 when engine coolant
temp. is 92C, 197F below.
2 driving cycle detection logic, continuous monitoring.
“B/W” or “P/G” circuit open or short

Radiator cooling 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.

6-1-86 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
Fig. 1 for Step 2 Fig. 2 for Step 3 Fig. 3 for Step 3
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 C02-18 of ECM
(PCM) connector connected, under following
condition. See Fig. 1.
When engine coolant temp. is lower than
92C, 197F 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 Cooling Fan Control Relay.
1) Turn ignition switch OFF and remove radiator
cooling fan relay.
2) Check for proper connection to the relay at
“B/W” and “P/G” wire terminals.
3) If OK, then measure resistance between
terminals a and b. See Fig. 2 and 3.
Is it 100 – 150 Ω?“B/W” or “P/G” circuit
open or short.
If wires and connections
are OK, substitute a
known-good ECM
(PCM) and recheck.Replace radiator
cooling fan relay.

ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-87
Vehicle speed
sensor in
combination meter
DTC P0500 VEHICLE SPEED SENSOR (VSS) MALFUNCTION FOR M / T
VEHICLE
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE

While fuel is kept cut at lower than 4000 r / min for
longer than 4 sec.

VSS signal not inputted.
2 driving cycle detection logic, continuous
monitoring.
Speedometer cable broken

“P”, “Y/G” or “B/Bl” circuit open or short

VSS malfunction

ECM (PCM) 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.
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.

6-1-88 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
Fig. 1 for Step 3 Fig. 2 for Step 4
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 (PCM) at terminal
C03-2.
3) If OK, then connect ohmmeter between terminal
C03-2 of ECM (PCM) connector and body ground.
4) Hoist front end of vehicle and lock front right tire.
5) Turn front left tire slowly.
Does ohmmeter indicator deflect between 0 and infinity a
few times while tire is turned one revolution?
See Fig. 1.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 and “GND”
terminal of combination meter and turn cable joint of
speedometer with a screwdriver. Ohmmeter indicator
should move back and forth between 0 and infinity
4 times while cable joint is turned one full revolution.
See Fig. 2.
Is it in good condition?“P”, “Y/G” or “B/Bl”
wire open or short,
or poor connection.Replace VSS.