2000 SUZUKI SWIFT CHECK

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.

1. Fuel pump
2. Fuel filter
3. Throttle body
4. Fuel injector
5. Fuel pressure regulator6. Special tool
(Fuel pressure gauge &
3-way joint)
7. Fuel feed line
8. Fuel return line
6-100 ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10)
TABLE B-3 FUEL PRESSURE CHECK
INSPECTION
STEPACTIONYESNO
1Check Fuel Pressure (Refer to Section 6E1 for details).
1) Release fuel pressure from fuel feed line.
2) Install fuel pressure gauge.
3) Check fuel pressure by repeating ignition switch
ON and OFF. See Fig. 1.
Is fuel pressure then 160 – 210 kPa (1.6 – 2.1 kg / cm
2,
22.7 – 29.9 psi)?
Go to Step 2.Go to Step 4.
2Is 90 kPa (0.9 kg / cm2, 12.8 psi) or higher fuel
pressure retained for 1 minute after fuel pump is
stopped at Step 1?Normal fuel pressure.Go to Step 3.
31) Start engine and warm it up to normal operating
temperature.
2) Keep it running at specified idle speed.
Is fuel pressure then within 90 – 140 kPa
(0.9 – 1.4 kg / cm
2, 12.8 – 20.0 psi)?
Normal fuel pressure.
Clogged vacuum
passage for fuel
pressure regulator
or

Faulty fuel pressure
regulator.
4Is there fuel leakage from fuel feed line hose, pipe or
their joint?Fuel leakage from
hose, pipe or joint.Go to Step 10.
5Was fuel pressure higher than specification in Step 1?Go to Step 6.Go to Step 7.
61) Disconnect fuel return hose from throttle body and
connect new return hose to it.
2) Insert the other end of new return hose into
approved gasoline container.
3) Operate fuel pump.
Is specified fuel pressure obtained then?Restricted fuel return
hose or pipe.Faulty fuel pressure
regulator.
7Was no fuel pressure supplied in Step 1?Go to Step 8.Go to Step 9.

ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-101
Fig. 1 for Step 1
1. Fuel pressure gauge & 3way joint
STEPACTIONYESNO
8With fuel pump operated and fuel return hose
blocked by pinching it, is fuel pressure applied?Faulty fuel pressure
regulator.Shortage of fuel or fuel
pump or its circuit
defective (refer to B-2
FUEL PUMP ANDITS
CIRCUIT CHECK).
91) Operate fuel pump.
2) With fuel return hose blocked by pinching it, check
fuel pressure.
Is it 450 kPa (4.5 kg / cm
2, 63.9 psi) or more?
Faulty fuel pressure
regulator.
Clogged fuel filter,

Restricted fuel feed
hose or pipe,

Faulty fuel pump or

Fuel leakage from
hose connection in
fuel tank.
101) Disconnect fuel return hose from throttle body and
connect new return hose to it.
2) Insert the other end of new return hose into
approved gasoline container.
3) Check again if specified pressure is retained.
While doing so, does fuel come out of return hose?Faulty fuel pressure
regulator.
Fuel leakage from
injector,

Fuel leakage from
between injector
and throttle body,

Faulty fuel pump
(faulty check valve
in fuel pump) or

Fuel leakage from
fuel pressure
regulator
diaphragm.

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.

Power steering
pressure
switch
ENGINE GENERAL INFORMATION AND DIAGNOSIS (TBI FOR G10) 6-103
TABLE B-5 POWER STEERING PRESSURE (PSP) SWITCH SIGNAL CIRCUIT
CHECK (IF EQUIPPED)
INSPECTION
STEPACTIONYESNO
1Check PSP Switch Signal Circuit.
1) Connect SUZUKI scan tool to DLC with ignition
switch OFF.
2) Start engine and select “DATA LIST” mode on
scan tool.
3) Check PSP switch signal under following each
condition. See Fig. 1.
Engine running and steering
wheel at straight-ahead position : OFF
Engine running and steering wheel
turned to the right on left as far as it stops : ON
Is check result satisfactory?PSP switch signal
circuit is in good
condition.“Bl / W” circuit open or
short, PSP switch
malfunction or power
steering system
malfunction.
Fig. 1 for Step 1