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Downloaded from www.Manualslib.com manuals search engine 6-96 ENGINE GENERAL INFORMATION AND DIAGNOSIS
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.
Page 455 of 687
Downloaded from www.Manualslib.com manuals search engine 6-98 ENGINE GENERAL INFORMATION AND DIAGNOSIS
DTC P0601 Internal Control Module Memory Check Sum Error (DTC No.71)
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON and then turn ignition switch OFF.
3) Start engine and run it at idle if possible.
4) Check pending DTC in “ON BOARD TEST” or “PENDING DTC” mode and DTC in “DTC” mode.
INSPECTION
Substitute a known-good ECM and recheck.DTC DETECTING CONDITION POSSIBLE CAUSE
DTC P0601 :
Data write error (or check sum error)
when written into ECM
✱
✱✱ ✱2 driving cycle detection logic, continuous monitoring.ECM
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Downloaded from www.Manualslib.com manuals search engine ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-99
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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Downloaded from www.Manualslib.com manuals search engine ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-101
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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Downloaded from www.Manualslib.com manuals search engine 6-102 ENGINE GENERAL INFORMATION AND DIAGNOSIS
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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Downloaded from www.Manualslib.com manuals search engine ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-103
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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Downloaded from www.Manualslib.com manuals search engine 6-104 ENGINE GENERAL INFORMATION AND DIAGNOSIS
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.
Page 462 of 687

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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.