2000 SUZUKI SWIFT ECM

ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-91
1. Relay box
2.“PTC”
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE DIAG.
FLOW TABLE”.
2Check EFE Heater and Its Circuit.
Check for voltage at terminal C01-12 of ECM (PCM)
connector connected, under following each
condition.
During engine warming up (Coolant temp.:
Below 80C, 176F, Engine speed: Over 750 r / min):
Over 1.0 V
After warming up: Below 1.0 V
Is each voltage as specified?Intermittent trouble.
Check for intermittent
referring to
“Intermittent and Poor
Connection” in
Section 0A.Go to Step 3.
3Check EFE Heater Relay.
1) Turn OFF ignition switch and remove EFE heater
relay (“PTC”). See Fig. 2.
2) Check for proper connection to relay at terminal
3 and 4. See Fig. 3.
3) Check resistance between each two terminals.
Between terminals 1 and 2: Infinity
Between terminals 3 and 4: 100 – 120 Ω
4) Check that there is continuity between terminals
1 and 2 when battery is connected to terminals
3 and 4. See Fig. 4.
Is EFE heater relay in good condition?Go to Step 4.Replace EFE heater
relay.
4Check EFE Heater and Its Circuit.
1) Turn ignition switch OFF and disconnect ECM
(PCM) connectors.
2) Check for proper connection to ECM (PCM) at
terminals C02-25 and C01-12.
3) If OK, then measure resistance between terminal
C01-12 and ground.
Is it 0.5 – 30 Ω at 20C (68F)?“W”, “Y/R” or “W/B”
circuit open or short.
If wire and
connections are OK,
substitute a known-
good ECM (PCM) and
recheck.“W/B” circuit open or
short.
If wire and
connections are OK,
replace EFE heater.
Fig 1. for Step 4 Fig. 2 for Step 3 Fig. 3 for Step 3
Fig. 4 for Step 3

6-92 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
Fig. 1 for Step 1
DTC P1450 BAROMETRIC PRESSURE SENSOR LOW / HIGH INPUT
DTC P1451 BAROMETRIC PRESSURE SENSOR PERFORMANCE PROBLEM
WIRING DIAGRAM / CIRCUIT DESCRIPTION
Barometric pressure sensor is installed in ECM (PCM).
DTC DETECTING CONDITION
POSSIBLE CAUSE
DTC P1450:

Barometric pressure: 136 kPa 1025 mmHg or higher, or
33 kPa 250 mmHg or lower
ECM (PCM) (barometric pressure sensor)
malfunction
DTC P1451:

Vehicle stopped.

Engine cranking.

Difference between barometric pressure and intake
manifold absolute pressure is 26 kPa, 200 mmHg or more.
2 driving cycle detection logic, monitoring once / 1 driving.
Manifold absolute pressure sensor and its
circuit malfunction

ECM (PCM) (barometric pressure sensor)
malfunction
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON.
3) Turn ignition switch ON for 2 sec., crank engine for 2 sec. and run it at idle for 1 min.
4) Check pending DTC in “ON BOARD TEST” or “PENDING DTC” mode and DTC in “DTC” mode.
INSPECTION
DTC P1450:
Substitute a known-good ECM (PCM) and recheck.
DTC P1451:
NOTE:
Note that atmospheric pressure varies depending on weather conditions as well as altitude.
Take that into consideration when performing these check.
STEP
ACTIONYESNO
11) Connect scan tool to DLC with ignition switch
OFF.
2) Turn ignition switch ON and select “DATA
LIST” mode on scan tool.
3) Check manifold absolute pressure. See Fig. 1.
Is it barometric pressure (approx. 100 kPa,
760 mmHg) at sea level?Substitute a known-
good ECM (PCM) and
recheck.Check intake manifold
pressure sensor and its
circuit.
Go to P0105 DIAG.
FLOW TABLE.

Main
fuse
M / T vehicle
Ignition
switch
(starter
switch)Starter
A / T vehicle
Main
fuse
Ignition
switch
(starter
switch)Transmission
range sensor (switch)
StarterPCM
ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-93
DTC P1500 ENGINE STARTER SIGNAL CIRCUIT MALFUNCTION
CIRCUIT DESCRIPTION
DTC DETECTING CONDITIONPOSSIBLE CAUSE

High voltage at terminal C01-16 for 3 min. after engine
start.

Low voltage at terminal C01-16 during starting engine.
2 driving cycle detection logic, continuous monitoring.
“B/Y” circuit open

ECM (PCM) malfunction
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON, crank engine and run it at idle for 3 min.
3) Check pending DTC in “ON BOARD TEST” or “PENDING DTC” mode and DTC in “DTC” mode.
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE DIAG.
FLOW TABLE”.
2Check for voltage at terminal C01-16 of ECM
(PCM) connector connected, under following
condition.
While engine cranking : 6 – 10 V
After starting engine : 0 V
Is voltage as specified?Poor C01-16
connection or
intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection”
in Section 0A.
If wire and connections
are OK, substitute a
known-good ECM (PCM)
and recheck.“B/Y” circuit open.

To DLC
“DOME” Main
fuse
6-94 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
DTC P1510 ECM (PCM) BACK-UP POWER SUPPLY MALFUNCTION
CIRCUIT DESCRIPTION
Battery voltage is supplied so that diagnostic trouble code memory, values for engine control learned by ECM
(PCM), etc. are kept in ECM (PCM) even when the ignition switch is turned OFF.
DTC DETECTING CONDITION
POSSIBLE CAUSE

Low voltage at terminal C02-14 after starting engine.
“W” circuit open

ECM (PCM) malfunction
DTC CONFIRMATION PROCEDURE
1) Clear DTC, start engine and run it at idle for 1 min.
2) Select “DTC” mode on scan tool and check DTC.
INSPECTION
STEPACTIONYESNO
1Check for voltage at terminal C02-14 of ECM
(PCM) connector connected, under each
condition, ignition switch OFF and engine
running.
Is it 10 – 14 V at each condition?Poor C02-14
connection or
intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection”
in Section 0A.
If wire and connections
are OK, substitute a
known- good ECM
(PCM) and recheck.“W” circuit open.

“IG
COIL
METER”
Main
fuseIgnition
switch
Main
relayTo other circuits
Injector resistor Fuel injector
6-96 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
TABLE B-1 FUEL INJECTOR CIRCUIT CHECK
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE DIAG.
FLOW TABLE”.
2Injector Circuit Check
1) Check injector circuit for short.
Is fuel injected from injector at ignition switch ON?“Y/B” wire shorted to
ground or faulty
injector.
If wire and injector is
as specified
respectively and then
substitute known-
good ECM (PCM) and
recheck.Go to Step 3.
3Injector Check
1) Check injector for fuel Injection referring to FUEL
INJECTOR ON-VEHICLE INSPECTION in
Section 6E1.
Is fuel injected from injector at engine cranking?Go to Step 4.Go to Step 5.
4Injector Leakage Check
1) Check injector for leaks referring to FUEL
INJECTOR ON-VEHICLE INSPECTION in
Section 6E1.
Is it in good condition?Injector and its circuit
are in good condition.Faulty fuel injector.
5Check Injector for Operating Sound.
1) Using sound scope, check injector for operating
sound at engine cranking.
Is it detected?Proceed to DIAG.
FLOW TABLE B-2 and
B-3.Go to Step 6.

ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-97
STEPACTIONYESNO
6Check Injector Resistor for Resistance.
1) Disconnect resistor connector with ignition switch
OFF.
2) Check for proper connection to resistor at each
terminals.
3) If connection is OK, check resistance.
Is resistance 1.9 – 2.1 Ω (at 20C, 68F)?“W/Bl”, “Y/G” or “Y/B”
wire open or poor
C02-12 connection.
If wires and
connections are OK,
substitute a known-
good ECM (PCM) and
recheck.Replace resistor.

6-98 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
Main
fuseIgnition
switchTo other circuits
Main
relay
Fuel pump relay
Fuel pump
CAUTION: Check to make sure that connection is
made between correct terminals. Wrong connection
can cause damage to ECM (PCM), wire harness, etc.
TABLE B-2 FUEL PUMP AND ITS CIRCUIT CHECK
INSPECTION
STEPACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE
DIAG. FLOW
TABLE”.
2Check Fuel Pump Control System for Operation. See Fig. 1.
Is fuel pump heard to operate for 2 sec. after ignition switch
ON?Fuel pump circuit
is in good
condition.Go to Step 3.
3Check Fuel Pump for Operation.
1) Remove fuel pump relay from relay box with ignition
switch OFF.
2) Check for proper connection to relay at each terminals.
3) If OK, using service wire, connect terminals E28-1 and
E28-2 of relay connector. See Fig. 2.
Is fuel pump heard to operate at ignition switch ON?Go to Step 4.“P”, “B” or “W/Bl”
circuit open or fuel
pump malfunction.
4Check Fuel Pump Relay for Operation.
1) Check resistance between each two terminals of fuel
pump relay. See Fig.3.
Between terminals “1” and “2”: Infinity
Between terminals “3” and “4”: 100 – 120 Ω
2) Check that there is continuity between terminals “1” and
“2” when battery is connected to terminals “3” and “4”. See
Fig. 4.
Is fuel pump relay in good condition?“P/W” circuit open
or poor C02-21
connection.
If wire and
connection are
OK, substitute a
known-good ECM
(PCM) and
recheck.Replace fuel pump
relay.

A/C
amplifier(A / C ON output signal)
(A / C input signal)
6-102 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
TABLE B-4 A / C SIGNAL CIRCUITS CHECK (VEHICLE WITH A / C)
INSPECTION
STEPACTIONYESNO
1Check A / C (Input) Signal Circuit.
1) Check voltage at terminal C03-19.
While engine running and A / C switch
and / or heater blower switch OFF
(A / C is not operating) : 10 – 14 V
While engine running and both A / C
switch and heater blower switch ON
(A / C is operating) : About 0 V
Are check results as specified?Go to Step 2.
“Bl / R” wire open or
short.

Poor C03-19
connection.

Poor A / C amplifier
coupler connection
or faulty A / C
system.
2Check A / C ON (Output) Signal Circuit.
1) Check voltage at terminal C03-17.
While engine running and A / C switch
and / or heater blower switch OFF
(A / C is not operating) : About 0 V
While engine running at idle speed
and both A / C switch and heater blower
switch ON (A / C is operating) : 10 – 14 V
Are check results as specified?A / C control signal
circuits are in good
condition.
“Lg / R” wire open or
short.

Poor performance of
ECT sensor, TP
sensor.

Engine start signal
inputted or

Poor C03-17
connection.
If none of the above
exists, substitute a
known-good ECM
(PCM) and recheck.