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[A] Fig. 1 for Step 2 / [B] Fig. 2 for Step 3 / [C] Fig. 3 for Step 44 Check Fuel Pump Relay for Operation.
1) Check resistance between each two termi-
nals of fuel pump relay. See Fig.3.
Fuel pump relay resistance
Between terminals “A” and “B” : Infinity
Between terminals “C” and “D”: 100 – 150
Ω
ΩΩ Ω
2) Check that there is continuity between ter-
minals “A” and “B” when battery is con-
nected to terminals “C” and “D”. See Fig. 3.
Is fuel pump relay in good condition?“W/G” circuit open or poor
E18-19 connection.
If wire and connection are
OK, substitute a known-
good ECM and recheck.Replace fuel pump
relay. Step Action Yes No
CAUTION:
Check to make sure that connection is made between correct terminals. Wrong connection can cause
damage to ECM, wire harness, etc.
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Table B-3 Fuel Pressure Check
INSPECTION
1. Injector 3. Fuel pump (B) : Hose
2. Delivery pipe (A) : Fuel pressure gauge (C) : Attachment
Step Action Yes No
1 Check Fuel Pressure (Refer to Section 6E for
details).
1) Release fuel pressure from fuel feed line.
2) Install fuel pressure gauge. See Fig.1.
3) Check fuel pressure by repeating ignition
switch ON and OFF.
Is fuel pressure then 270 – 310 kPa
(2.7 - 3.1 kg/cm
2, 38.4 – 44.0 psi)?Go to Step 2. Go to Step 4.
2
Is 250 kPa (2.5 kg/cm
2, 35.6 psi) or higher fuel
pressure retained for 1 minute after fuel pump is
stopped at Step 1?Normal fuel pressure. Go to Step 3.
3 Is there fuel leakage from fuel feed line hose,
pipe or their joint?Fuel leakage from hose,
pipe or joint.Faulty fuel pressure regu-
lator.
4 Was fuel pressure higher than spec. in Step 1? Faulty fuel pressure regu-
lator.Clogged fuel filter,
Restricted fuel feed hose
or pipe, Faulty fuel pump
or Fuel leakage from hose
connection in fuel tank.
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Table B-4 Idle Air Control System Check
INSPECTION
1. Main fuse 2. Fuse box 3. Main relay 4. IAC valve
Step Action Yes No
1 Check engine idle speed and IAC duty referring to
“Idle Speed / IAC Duty Inspection” in Section 6E.
Is idle speed within specification?Go to Step 2. Go to Step 4.
2 Is IAC duty within specification in Step 1? Go to Step 3. Check for followings :
Vacuum leak
EVAP canister purge
control system
Clog of IAC air pas-
sage
Accessory engine
load
Closed throttle posi-
tion (TP sensor)
Stuck of PCV valve
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3 Is engine idle speed kept specified speed even
with headlight ON?System is in good condi-
tion.Check IAC system for
operation referring to
Step 3 or Step 4 of DTC
P0505 Diag. Flow Table.
4 Was idle speed higher than specification in Step
1?Go to Step 5. Go to Step 8.
5 Check A/C (input) signal circuit referring to Step 1
of Table B-5 A/C Signal Circuit Check, if
equipped. (A/C signal can be also checked by
using SUZUKI scan tool.)
Is it in good condition?Go to Step 6. Repair or replace A/C
signal circuit or A/C sys-
tem.
6 Check IAC system referring to Step 2 to Step 4 of
DTC P0505 Diag. Flow Table.
Is check result satisfactory?Go to Step 7. Go to Step 5 of DTC
P0505 Diag. Flow Table.
7 Was IAC duty less than about 3% (or more than
about 97% for OFF duty meter) in Step 1 of this
table?Check abnormal air
inhaling from air intake
system, PCV valve and
EVAP canister purge
control system.Check TP sensor
(closed throttle position)
and ECT sensor for per-
formance.
If sensors are OK, sub-
stitute a known-good
ECM.
8 Is SUZUKI scan tool available? Go to Step 9. Go to Step 10.
9 Check PNP signal (“D” range signal).
1) Connect SUZUKI scan tool to DLC with igni-
tion switch OFF.
2) Turn ignition switch ON and check PNP signal
(“P/N” and “D” range) on display when shifting
selector lever to each range. See Table 1.
Is check result satisfactory?Go to Step 11. Repair or replace.
10 Check PNP signal (“D” range signal).
1) Turn ignition switch ON.
2) Check voltage at terminal E17-6 of ECM con-
nector connected. See Fig. 1 and Table 1.
Is check result satisfactory?Go to Step 11. Repair or replace.
11 Check IAC system referring to Step 2 to Step 4 of
DTC P0505 Diag. Flow Table.
Is check result satisfactory?Go to Step 12. Go to Step 5 of DTC
P0505 Diag. Flow Table.
12 Was IAC duty more than about 30% or ✱40% (or
less than 70% or ✱60% for OFF duty meter) in
Step 1 of this table? See NOTE.Check parts or system
which can cause engine
low idle.
Accessory engine load
Clog of air passage
Etc.Substitute a known-good
ECM and recheck. Step Action Yes No
NOTE:
Duty value with (
✱
✱✱ ✱) are applicable to vehicle used at high altitude (higher than 2000 m or 6560 ft).
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Fig. 1 for Step 10
Table 1 for Step 9 and 10
Scan tool or voltmeter
SUZUKI SCAN TOOL
DISPLAYVOLTAGE AT E17-6
Selector lever
position“P” and “N” range P/N range 10 – 14V
“R”, “D”, “2” and “L” range D range 0 – 1V
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Table B-5 A/C Signal Circuits Check (Vehicle with A/C)
1. A/C compressor magnet clutch 4. A/C condenser fan 7. Evaporator temp. sensor
2. A/C switch 5. Refrigerant pressure switch [A] : Case of TYPE A is shown (See NOTE)
3. Blower fan 6. ECT sensor [B] : Case of TYPE B is shown (See NOTE)
NOTE:
For TYPE A and TYPE B, refer to the NOTE in “ECM Terminal Voltage Values Table” for applicable
model.
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INSPECTION
Fig. 1 for Step 1Step Action Yes No
1 Check evaporator temp. sensor.
1) Disconnect ECM connectors with ignition
switch at OFF position.
2) Check resistance between E19-14 terminal
and E19-10 terminal.
Reference value
(Refer to characteristic curve below)
ECT sensor resistance
At 0°C 6.3 – 6.9 k
Ω
ΩΩ Ω
At 25°C 1.8 – 2.2 k
Ω
ΩΩ Ω
Is it within specification?Go to Step 2. Faulty A/C evaporator
thermistor or its circuit.
2 Check A/C switch circuit.
1) Check voltage at E18-16 terminal under
each condition given below.
A/C switch signal specification
Ignition switch ON A/C switch OFF
: 10 – 14 V
Ignition switch ON A/C switch ON
: 0 – 1 V
Is check result satisfactory?Go to Step 3.“G/W” wire open or short
Poor E18-16 terminal con-
nection
If wire and connection are
OK, substitute a known-
good ECM and recheck.
Go to Step 3.
3 Check A/C compressor signal.
1) Check voltage at E18-1 terminal under each
condition given below. See NOTE.
A/C compressor signal specification
While engine running, A/C switch OFF
: 0 V
While engine running, A/C switch ON
: 10 – 14 V
Is check result satisfactory?A/C control system cir-
cuits are in good condi-
tion.“P” wire open or short
Poor E18-1 terminal con-
nection
If wire and connection are
OK, substitute a known-
good ECM and recheck.
NOTE:
When A/C evaporator thermistor temp. is below 2.5 °C (36.5 °F), A/C remain OFF (E18-1 terminal volt-
age become 0 – 1 V). This condition is not abnormal.
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Table B-6 Electric Load Signal Circuit Check
INSPECTION
1. Rear defogger switch 3. Blower fan switch [B] : Case of TYPE B is shown (See NOTE)
2. Light switch [A] : Case of TYPE A is shown (See NOTE)
NOTE:
For TYPE A and TYPE B, refer to the NOTE in “ECM Terminal Voltage Values Table” for applicable
model.
Step Action Yes No
1 Is SUZUKI scan tool available? Go to Step 2. Go to Step 3.
2 Check Electric Load Signal Circuit.
1) Connect SUZUKI scan tool to DLC with igni-
tion switch OFF. See Fig.1.
2) Start engine and select “DATA LIST” mode
on scan tool.
3) Check electric load signal under following
each condition. See Table 1.
Is check result satisfactory?Electric load signal circuit
is in good condition.“R/W”, “R/Y” and/or “Bl/Y”
circuit open or short, Elec-
tric load diodes malfunc-
tion or Each electric load
circuit malfunction.
3 Check Electric Load Signal Circuit.
1) Turn ignition switch ON.
2) Check voltage at each terminals E17-16,
E18-17 and E18-24 (Case of TYPE A) or
E18-12, E18-17 and E17-13 (Case of TYPE
B) (See NOTE) of ECM connector con-
nected, under above each condition. See
Fig. 2. and Table 1.
Is each voltage as specified?Electric load signal circuit
is in good condition.“R/W”, “R/Y” and/or “Bl/Y”
circuit open or short, Elec-
tric load diodes malfunc-
tion or Each electric load
circuit malfunction.