ECT sensor SUZUKI JIMNY 2005 3.G Service Workshop Manual

Downloaded from www.Manualslib.com manuals search engine 6-94 ENGINE GENERAL INFORMATION AND DIAGNOSIS
DTC P0500 (DTC No.16) Vehicle Speed Sensor (VSS) Malfunction
CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
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.
1. VSS 3. VSS connector [B] : Case of TYPE B is shown (See NOTE)
2. Combination meter [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.
DTC DETECTING CONDITION POSSIBLE 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/Or” circuit open
“Y” or “Bl/B” circuit open or short
VSS malfunction
ECM malfunction
Speedometer malfunction
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic acci-
dent 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.

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INSPECTION
[A] Fig. 1 for Step 5 / [B] Fig. 2 for Step 4 and Step 6Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag. Flow
Table”.
2 Does speedometer indicate vehicle speed? Go to Step 3. Go to Step 5.
3 Check Vehicle Speed Signal.
Is vehicle speed displayed on scan tool in step
2) and 3) of DTC confirmation procedure?Intermittent trouble or
faulty ECM.
Check for intermittent
referring to “Intermittent
and Poor Connection” in
Section 0A.Go to Step 4.
4 1) Turn ignition switch to OFF position.
2) Disconnect combination meter connec-
tors.Refer to Section 8.
3) Turn ignition switch to ON position, without
running engine.
4) Measure voltage from terminal “c” of VSS
connector to ground. See Fig.2.
Is voltage within 4 – 5 V?Faulty speedometer.“Y” or “Y/G” wire open or
short.
Poor connection of ECM
connector terminal.
If OK, substitute a known-
good ECM and recheck.
5 1) With ignition switch at OFF position, discon-
nect VSS connector.
2) Turn ignition switch to ON position, without
running engine.
3) Measure voltage from terminal “a” to “b” of
VSS connector. See Fig.1.
Is voltage within 10 – 14 V?Go to Step 6.“Bl/B” or “B/Or” wire open
or short.
6 1) Measure voltage from terminal “c” of VSS
connector to ground. See Fig.2.
Is voltage more than 4 V?Go to Step 7.“Y” or “Y/G” wire open or
short.
Poor connection of ECM
connector terminal.
If OK, substitute a known-
good ECM and recheck.
7 1) Remove VSS.
2) Visually inspect VSS sensor signal rotor for
damage.
Was any damage found?Faulty VSS signal rotor. Poor connection of VSS
connector terminal.
If OK, substitute a known-
good VSS and recheck.

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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.
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 and recheck.
DTC P1451 :
DTC DETECTING CONDITION POSSIBLE CAUSE
DTC P1450 :
Barometric pressure sensor voltage is 4.7 V or higher, or
1.6 V or lowerECM (barometric pressure sensor) malfunc-
tion
DTC P1451 :
Vehicle stopped
Engine cranking
Difference between barometric pressure and intake mani-
fold absolute pressure is 26 kPa, 200 mmHg or more.
Difference between intake manifold absolute pressure at
engine start and pressure after engine start is less than 1.3
kPa, 10 mmHg.
✱
✱✱ ✱2 driving cycle detection logic, monitoring once / 1 driving.ECM (barometric pressure sensor) malfunc-
tion
NOTE:
Note that atmospheric pressure varies depending on weather conditions as well as altitude.
Take that into consideration when performing these check.
Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag. Flow
Table”.
2 1) Connect scan tool to DLC with ignition
switch OFF. See Fig.1.
2) Turn ignition switch ON and select “DATA
LIST” mode on scan tool.
3) Check manifold absolute pressure.
Is it barometric pressure (approx. 100 kPa, 760
mmHg) at sea level?Substitute a known-good
ECM and recheck.Go to Step 3.

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[A] Fig. 1 for Step 2 / [B] Fig. 2 for Step 3
Table 13 Check MAP Sensor
1) Remove MAP sensor from intake manifold
and connect vacuum pump gauge to MAP
sensor. See Fig. 2.
2) Connect scan tool to DLC and turn ignition
switch ON.
3) Check intake manifold absolute pressure
displayed on scan tool for specified value.
See Table 1.
Is check result satisfactory?Check air intake system
for air being drawn in and
engine compression.
If OK, then substitute a
known-good ECM and
recheck.Replace MAP sensor. Step Action Yes No
Applying Vacuum Displayed Value on Scan Tool
0 Barometric pressure
(Approx. 100 kPa, 760 mmHg)
027 kPa
200 mmHgBarometric pressure – 27 kPa
(Approx. 73 kPa, 560 mmHg)
67 kPa
500 mmHgBarometric pressure – 67 kPa
(Approx. 33 kPa, 260 mmHg)

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DTC P1500 Engine Starter Signal Circuit Malfunction
CIRCUIT DESCRIPTION
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.
1. Starter 3. Ignition switch (starter switch) [A] : Case of TYPE A is shown (See NOTE) [C] : M/T vehicle
2. Transmission range sensor (switch) 4. Main fuse [B] : Case of TYPE B is shown (See NOTE) [D] : A/T vehicle
NOTE:
For TYPE A and TYPE B, refer to the NOTE in “ECM Terminal Voltage Values Table” for applicable
model.
DTC DETECTING CONDITION POSSIBLE CAUSE
Low voltage at terminal E17-13 or E18-20 when cranking
engine or
High voltage at terminal E17-13 or E18-20 after starting
engine.
✱
✱✱ ✱2 driving cycle detection logic, continuous monitoring.“B/Y” circuit open
ECM malfunction

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INSPECTION
[A] Fig. 1 for Step 3 / [B] Fig. 2 for Step 4 / [C] Fig. 3 for Step 6Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag. Flow
Table”.
2 Is SUZUKI scan tool available? Go to Step 3. Go to Step 4.
3 Check PNP signal (“D” range signal).
1) Connect SUZUKI scan tool to DLC with igni-
tion switch OFF. See Fig. 1.
2) Turn ignition switch ON and check PNP sig-
nal (“P/N” or “D” range) on display when
shifting selector lever to each range.
Is “D” range on display (Is 0 – 1 V indicated) no
matter which of “R”, “D”, “2” and “L” range posi-
tions selector lever may be at? See Table 1.Intermittent trouble or
faulty ECM. Check for
intermittent referring to
“Intermittent and Poor
Connection” in Section
0A.Go to Step 5.
4 Check PNP Signal (“D” range signal).
1) Turn ignition switch ON.
2) Check voltage at terminal E17-6 of ECM
connector connected. See Fig. 2.
Is “D” range on display (Is 0 – 1 V indicated) no
matter which of “R”, “D”, “2” and “L” range posi-
tions selector lever may be at? See Table 1.Intermittent trouble or
faulty ECM. Check for
intermittent referring to
“Intermittent and Poor
Connection” in Section
0A.Go to Step 5.
5Is “P/N” range on display (Is 10 – 14 V indi-
cated) when selector lever is at one of “R”, “D”,
“2” and “L” range positions only?Check transmission range
switch and circuits refer-
ring to Section 7B.Go to Step 6.
6 Check PNP signal circuit.
1) Turn ignition switch OFF.
2) Disconnect TCM connectors.
3) Check for proper connection to TCM at ter-
minal E21-5.
4) If OK, then check voltage at terminal E21-8
in TCM connector disconnected, with igni-
tion switch ON. See Fig. 3
Is it 10 – 14 V?“Y/B” circuit open, poor
transmission range sen-
sor connector connec-
tion, select cable
maladjusted, transmis-
sion range sensor malad-
justed or transmission
range sensor malfunction.
If all above are OK, sub-
stitute a known-good TCM
and recheck.“G/Y” circuit open or poor
E17-6 connection.
If wire and connection are
OK, substitute a known-
good ECM and recheck.

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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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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.