ECT SUZUKI JIMNY 2005 3.G Service Workshop Manual

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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
Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag. Flow
Table”.
2 Check for voltage at terminal E17-13 (Case of
TYPE A) (See NOTE) or E18-20 (Case of TYPE
B) (See NOTE) of ECM connector connected,
under following condition.
Engine starter signal specification
While engine cranking : 6 – 10 V
After starting engine : 0 V
Is voltage as specified?Poor E17-13 (Case of
TYPE A) (See NOTE) or
E18-20 (Case of TYPE B)
(See NOTE) 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.“B/Y” or “B/R” circuit
open.

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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.

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[A] Fig. 1 for Step 2 / [B] Fig. 2 for Step 43 Is it about 12 V at Step 2?“B/R” wire open, poor
E21-11 connection or
TCM power or ground cir-
cuit open.
If wires and connections
are OK, substitute a
known-good TCM and
recheck.Go to Step 4.
4 Check signal circuit.
1) Disconnect TCM coupler with ignition switch
OFF.
2) Check voltage between E21-20 terminal
and body ground with ignition switch ON.
See Fig. 2.
Is it about 12 V?Check TCM power and
ground circuit for open.
If OK, substitute a known-
good TCM and recheck.“B/R” wire shorted to
ground or poor E17-17
terminal connection.
If wire and connection are
OK, substitute a known-
good ECM and recheck. Step Action Yes No

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DTC P1717 A/T Drive Range (Park / Neutral Position) Signal Circuit Malfunc-
tion
CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON.
3) Start engine and shift selector lever to “D” range.
4) Increase vehicle speed to higher than 20 mph, 32 km/h and then stop vehicle.
5) Repeat above step 4) 9 times.
6) Shift selector lever to “2” range and repeat above step 4) and 5).
7) Shift selector lever to “L” range and repeat above step 4) and 5).
8) Check DTC in “DTC” mode and pending DTC in “ON BOARD TEST” or “PENDING DTC” mode.
1. Transmission range switch 2. From ignition switch 3. TCM
DTC DETECTING CONDITION POSSIBLE CAUSE
“D” range signal not inputted (Park / Neutral position
signal inputted) to ECM while vehicle running
✱
✱✱ ✱2 driving cycle detection logic, Continuous monitoring.“G/Y” circuit open
Transmission range switch malfunction
“R”, “D”, “2” or “L” range signal circuit open
TCM power or ground circuit open
TCM malfunction
ECM 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 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.