2005 SUZUKI JIMNY Service Workshop Manual

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[A] Fig. 1 for Step 3 / [B] Fig. 2 for Step 6 / [C] Fig. 3 for Step 6
Fig. 4 for Step 7

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DTC P0400 Exhaust Gas Recirculation Flow Malfunction
CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
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)
–Ambient temp. : –10 °C, 14 °F or higher
–Intake air temp. : 70 °C, 122 °F or lower
1. EGR valve
DTC DETECTING CONDITION POSSIBLE CAUSE
While running at specified vehicle speed after engine warm-up
During deceleration (engine speed high with closed throttle position
ON) in which fuel cut is involved, difference in intake manifold absolute
pressure between when EGR valve is opened at specified value and
when it is closed is larger or smaller than specified value.
✱
✱✱ ✱2 driving cycle detection logic, monitoring once / 1 drivingEGR valve or its circuit
EGR passage
ECM
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, on a level road.

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2) Start engine and warm it up to normal operating temperature (70 – 110 °C, 158 – 230 °F) and run it at idle
for 5 min.
3) Increase vehicle speed to 50 – 55 mph, 80 – 88 km/h in 5th gear or in “D” range.
4) Hold throttle valve at that opening position for 2 min. or longer.
5) Increase engine speed to 4000 r/min. in 3rd gear or in “2” range.
6) Release accelerator pedal and with engine brake applied, keep vehicle coasting (fuel cut condition) till
engine speed reaches 1500 r/min.
7) Stop vehicle (don’t turn ignition switch OFF) and confirm test results according to following “Test Result Con-
firmation Flow Table.”
Test Result Confirmation Flow Table
INSPECTION
Step Action Yes No
1 Check DTC in “DTC” mode and pending DTC in
“ON BOARD TEST”.
Is DTC or pending DTC displayed?Proceed to applicable
DTC flow table.Go to Step 2.
2 Set scan tool to “READINESS TESTS” mode
and check if testing has been completed.
Is test completed?No DTC is detected.
(Confirmation test is com-
pleted)Repeat DTC confirmation
procedure.
Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag. Flow
Table”.
2 1) Turn ignition switch ON.
2) Does EGR stepper motor operation for 0.6
second after ignition switch OFF?Go to Step 3. Go to Step 6.
3 With ignition switch at OFF, check voltage
between E19-28, 17, 29, 18 terminals of ECM
and body ground. See Fig. 2.
Is voltage about 0 V?Go to Step 4. Go to Step 8.

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[A] Fig. 1 for Step 7 / [B] Fig. 2 for Step 3 and 44 With ignition switch at ON, check voltage
between E19-28, 17, 29, 18 terminals of ECM
and body ground. See Fig. 2.
Is voltage within 10 – 14 V?Go to Step 5. Go to Step 8.
5 Do you have SUZUKI scan tool? Go to Step 6. Stuck or faulty EGR valve
or clogged EGR gas pas-
sage.
If all above are OK, sub-
stitute a known-good
ECM and recheck.
6 Check EGR system referring to “EGR System”
in Section 6E.
Is check result satisfactory?Substitute a known-good
ECM and recheck.Stuck or faulty EGR valve
or clogged EGR gas pas-
sage.
7 1) Disconnect EGR valve connector with igni-
tion switch OFF.
2) Check voltage between “Bl/B” wire terminal
(2) of EGR valve connector (1) and body
ground with ignition switch ON. See Fig. 1.
3) Are they about 10 – 14 V?Go to Step 3.“Bl/B” wire open or short.
8 Check EGR valve referring to “EGR System” in
Section 6E.
Is it good condition?EGR valve harness
(“Gr/B”, “Gr/Bl”, “Gr/R” or
“Gr” wire) open or short or
poor connector connec-
tion (EGR valve connec-
tor, E19-28, 17, 29, 18) If
wire harness and connec-
tion are OK, substitute a
known-good ECM and
recheck.Faulty EGR valve. Step Action Yes No

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DTC P0420 Catalyst System Efficiency below Threshold
CIRCUIT DESCRIPTION
ECM 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
1. Heated oxygen sensor-1 3. Three way catalytic converter 5. To the sensor [B] : Case of TYPE B is shown
(See NOTE)
2. Warm up three way catalytic
converter4. Heated oxygen sensor-2 [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.
1. Engine running at closed loop
condition2. Fuel cut 3. Idle after fuel cut [A] : Oscilloscope waveforms

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DTC CONFIRMATION PROCEDURE
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)
–Ambient temp. : –10 °C, 14 °F or higher
–Intake air temp. : 70 °C, 158 °F or lower
–Engine coolant temp. : 70 – 110 °C, 158 – 230 °F
2) Start engine and drive vehicle at 35 – 45 mph, 55 – 65 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 30 – 40 mph, 50 – 60 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
Confirmation Flow Table”. DTC DETECTING CONDITION POSSIBLE 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 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
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, on a level road.

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Test Result Confirmation Flow Table
INSPECTION
Step Action Yes No
1 Check 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.
2 Set scan tool to “READINESS TESTS” mode
and check if testing has been completed.
Is test completed?No DTC is detected (con-
firmation test is com-
pleted).Repeat DTC confirmation
procedure.
Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag. Flow
Table”.
2 Check 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.
3 Check HO2S-2 for Output Voltage.
Perform steps 1) through 9) of DTC confirma-
tion procedure for DTC P0136 (HO2S-2 mal-
function) and check output voltage of HO2S-2
then.
Is over 0.6 V and below 0.3 V indicated?Replace three way cata-
lytic converter.Check “W” and “B/Bl”
wires for open and short,
and connections for poor
connection.
If wires and connections
are OK, replace HO2S-2.

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DTC P0443 Purge Control Valve Circuit Malfunction
CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
1) Clear DTC with ignition switch ON.
2) Select “DTC” mode on scan tool and check DTC.
INSPECTION
Fig. 1 for Step 2
1. EVAP canister purge vale
DTC DETECTING CONDITION POSSIBLE CAUSE
Canister Purge control valve circuit is opened or
shorted.“Bl/G” circuit open or short
“Bl/B” circuit open or short
Canister purge valve malfunction
Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2 Go to “Engine Diag.
Flow Table”.
2 Check EVAP canister purge valve operation
1) With ignition switch OFF, disconnect coupler from
canister purge valve.
2) Check resistance of EVAP canister purge valve.
See Fig.1
EVAP canister purge valve resistance
Between two terminals : 30 – 34
Ω
ΩΩ Ω at 20 °C (68 °F)
Between terminal and body : 1M
Ω
ΩΩ Ω or higher
Is it as specified?“Bl/G” circuit open or
short.Replace EVAP canister
purge valve.