GENERAL DESCRIPTION SUZUKI JIMNY 2005 3.G Service Repair Manual

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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 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.

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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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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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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.

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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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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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DTC P1510 ECM Back-up Power Supply Malfunction
CIRCUIT DESCRIPTION
Battery voltage is supplied so that diagnostic trouble code memory, values for engine control learned by ECM,
etc. are kept in ECM even when the ignition switch is turned OFF.
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
1. Main fuse
2. Fuse box
DTC DETECTING CONDITION POSSIBLE CAUSE
Low voltage at terminal E18-7 after starting engine.“W” circuit open
ECM malfunction
Step Action Yes No
1 Check for voltage at terminal E18-7 of ECM
connector connected, under each condition,
ignition switch OFF and engine running.
Is it 10 – 14 V at each condition?Poor E18-7 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 and
recheck.“W” circuit open.

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DTC P1570 (DTC No.21) ABS Signal Circuit Malfunction
CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
1) Clear DTC, start engine and keep it at idle for 1 min.
2) Select “DTC” mode on scan tool and check DTC.
INSPECTION
DTC DETECTING CONDITION POSSIBLE CAUSE
ABS signal input is low when engine start.ABS signal circuit short to ground
ABS control module
Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag. Flow
Table”.
2 1) With the ignition switch ON position, check
voltage between E17-12 terminal of ECM
coupler and ground.
Is voltage within 10 – 14 V?Intermittent trouble.
If OK, substitute a known-
good ECM and recheck.Go to Step 3.
3 1) Check “G” wire for shorted to ground circuit.
Is “G” wire in good condition?Go to Step 4. Repair or replace.
4 1) Disconnect coupler of ABS control module.
2) Clear DTC.
3) Start engine and check DTC.
Is DTC P1570 (No.21) detected?Substitute a known-good
ECM and recheck.Substitute a known-good
ABS control module and
recheck.

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DTC P1600 Serial Communication Problem Between ECM and TCM
CIRCUIT DESCRIPTION
The serial data line is pulled up to about 12 V by ECM and TCM transmits information to ECM through it by con-
trolling its grounding.
TCM constantly sends information while ignition switch is ON as to whether judgement was made or not with
respect to all detectable DTCs as well as whether or not abnormality exists after judgement.
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) Select “DTC” mode on scan tool and check DTC.
INSPECTION
DTC DETECTING CONDITION POSSIBLE CAUSE
No signal inputted from TCM to ECM or check sum
error while engine running“G/R” circuit open or short
TCM power or ground circuit open.
TCM malfunction
ECM malfunction
Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag. Flow
Table”.
2 Check signal voltage.
Check voltage between terminal E17-17 and
body ground with ignition switch ON. See Fig. 1.
Does it change between 0 – 12 V?Intermittent trouble or
faulty ECM or TCM.
Check for intermittent
trouble referring to “Inter-
mittent and Poor Connec-
tion” in Section 0A.Go to Step 3.