2005 SUZUKI JIMNY ecm

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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 P0481 A/C Condenser Fan Control Circuit Malfunction
CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON.
3) Start engine and then turn both A/C switch and heater blower switch ON for 2 sec or more.
4) Run engine at idle for 5 sec or more which A/C switch and heater blower switch OFF.
5) Check DTC and pending DTC.
1. Ignition switch 3. A/C condenser fan relay 5. A/C condenser fan 7. Fuse box
DTC DETECTING CONDITION POSSIBLE CAUSE
Low voltage at terminal E18-18 when ECM doesn’t out-
put A/C ON signal to A/C amplifier or when engine cool-
ant temp. is not 110 °C (230 °F) or more.
✱
✱✱ ✱2 driving cycle detection logic, continuous monitoring.“P/B” or “Lg” circuit open or short
Condenser fan motor relay malfunction
ECM malfunction

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INSPECTION
[A] Fig. 1 for Step 3 / [B] Fig. 2 for Step 3Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag.
Flow Table”.
2 Check A/C Condenser Fan Control Relay and its
Circuit.
1) Turn ignition switch ON.
2) Check for voltage at terminal E18-18 of ECM
connector connected, under following condition.
When A/C switch turns OFF : 10 – 14 V
Is voltage as specified?Intermittent trouble or
faulty ECM.
Check for intermittent
referring to “Intermittent
and Poor Connection” in
Section 0A.Go to Step 3.
3 Check A/C Condenser Fan Control Relay.
1) Turn ignition switch OFF and remove A/C con-
denser fan control relay (1). See Fig.1.
2) Check for proper connection to the relay at “P/B”
and “Lg” wire terminals.
3) If OK, then measure resistance between termi-
nals C and D. See Fig.2.
Is it 70 - 110Ω?“Lg” or “P/B” circuit open
or short.
If wires and connections
are OK, substitute a
known-good ECM and
recheck.Replace A/C con-
denser fan control
relay.

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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 P0505 Idle Control System Malfunction
CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON.
3) Start engine and run it at idle for 1 min.
4) Check DTC and pending DTC.
INSPECTION
1. IAC valve 3. Ignition switch 5.“FI” fuse
2. Main relay 4.“IG COIL METER” fuse .
DTC DETECTING CONDITION POSSIBLE CAUSE
No closed signal to IAC valve is detected after
engine start.
✱
✱✱ ✱2 driving cycle detection logic, continuous monitoring.“Bl/B”, “G/Y” or “B/R” circuit open or short
IAC valve malfunction
ECM malfunction
Step 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.