Downloaded from www.Manualslib.com manuals search engine ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-9
On-Board Diagnostic System (Vehicle without
Immobilizer Indicator Lamp)
ECM diagnosis troubles which may occur in the area including
the following parts when the ignition switch is ON and the engine
is running, and indicates the result by turning on or flashing mal-
function indicator lamp (1).
Heated oxygen sensor (if equipped)
ECT sensor
TP sensor
IAT sensor
MAP sensor
CMP sensor
CKP sensor
Knock sensor
VSS
CPU (Central Processing Unit) of ECM
ECM and malfunction indicator lamp (1) operate as follows.
Malfunction indicator lamp (1) lights when the ignition switch
is turned ON (but the engine at stop) with the diagnosis
switch terminal ungrounded regardless of the condition of
Engine and Emission Control system. This is only to check
the malfunction indicator lamp (1) bulb and its circuit.
If the above areas of Engine and Emission Control system is
free from any trouble after the engine start (while engine is
running), malfunction indicator lamp (1) turns OFF.
When ECM detects a trouble which has occurred in the
above areas, it makes malfunction indicator lamp (1) turn ON
while the engine is running to warn the driver of such occur-
rence of trouble and at the same time it stores the trouble
area in ECM back-up memory. (The memory is kept as it is
even if the trouble was only temporary and disappeared
immediately. And it is not erased unless the power to ECM is
shut off for specified time below.)
ECM also indicates trouble area in memory by means of
flashing of malfunction indicator lamp (1) at the time of
inspection. (i.e. when connecting diagnosis switch terminal
(2) and ground terminal (4) of monitor connector (3) with a
service wire (5) and ignition switch is turned ON.)
NOTE:
When a trouble occurs in the above areas and disap-
pears soon while the diagnosis switch terminal is
ungrounded and the engine is running, malfunction
indicator lamp (1) lights and remains ON as long as the
trouble exists but it turns OFF when the normal condi-
tion is restored.
Time required to erase diagnostic trouble code mem-
ory thoroughly varies depending on ambient tempera-
ture as follows.
Downloaded from www.Manualslib.com manuals search engine 6-14 ENGINE GENERAL INFORMATION AND DIAGNOSIS
Malfunction indicator lamp (MIL) check
1) Turn ON ignition switch (but the engine at stop) and check
that MIL lights.
If MIL does not light up (or MIL dims), go to “Diagnostic Flow
Table A-1” for troubleshooting.
If MIL flushes, go to “Diagnostic Flow Table A-3” for trouble
shooting (vehicle without immobilizer indicator lamp).
2) Start engine and check that MIL turns OFF.
If MIL remains ON and no DTC is stored in ECM, go to
“Diagnostic Flow Table A-2” for troubleshooting.
Diagnostic trouble code (DTC) check
[Using SUZUKI Scan Tool]
1) Prepare SUZUKI scan tool.
2) With ignition switch OFF, connect it to data link connector
(DLC) (1) located on underside of instrument panel at
driver’s seat side.
Special tool
(A) : SUZUKI scan tool
3) Turn ignition switch ON and confirm that MIL lights.
4) Read DTC, pending DTC and freeze frame data according to
instructions displayed on scan tool and print it or write it
down.
Refer to scan tool operator’s manual for further details.
If communication between scan tool and ECM is not possi-
ble, check if scan tool is communicable by connecting it to
ECM in another vehicle. If communication is possible in this
case, scan tool is in good condition. Then check data link
connector and serial data line (circuit) in the vehicle with
which communication was not possible.
5) After completing the check, turn ignition switch off and dis-
connect scan tool from data link connector.
[Without Using SUZUKI Scan Tool] (Vehicle Without
Immobilizer Indicator Lamp)
1) Check malfunction indicator lamp referring to “Malfunction
Indicator Lamp Check” in this section.
2) With the ignition switch OFF position, connect diagnosis
switch terminal (3) and ground terminal (2) in monitor con-
nector (1) with service wire (4).
3) With the ignition switch ON position and leaving engine OFF,
read DTC from flashing pattern of malfunction indicator
lamp. Refer to “Diagnostic Trouble Code Table”.
If lamp does not flash or remains ON or OFF, go to “Diag-
nostic Flow Table A-4”.
Downloaded from www.Manualslib.com manuals search engine ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-15
4) After completing the check, turn the ignition switch OFF posi-
tion and disconnect service wire from monitor coupler.
Diagnostic trouble code (DTC) clearance
[Using SUZUKI Scan Tool]
1) Connect SUZUKI scan tool to data link connector in the
same manner as when making this connection for DTC
check.
2) Turn ignition switch ON.
3) Erase DTC and pending DTC according to instructions dis-
played on scan tool. Refer to scan tool operator’s manual for
further details.
4) After completing the clearance, turn ignition switch off and
disconnect scan tool from data link connector.
[Without Using SUZUKI Scan Tool]
1) Turn the ignition switch OFF position.
2) Disconnect battery negative cable for specified time below to
erase diagnostic trouble code stored in ECM memory and
reconnect it.
Time required to erase DTC NOTE:
If abnormality or malfunction lies in two or more areas,
malfunction indicator lamp indicates applicable codes
three times each.
And flashing of these codes is repeated as long as
diagnosis terminal is grounded and ignition switch is
held at ON position.
Take a note of diagnostic trouble code indicated first.
NOTE:
DTC and freeze frame data stored in ECM memory are
also cleared in following cases. Be careful not to clear
them before keeping their record.
When power to ECM is cut off (by disconnecting bat-
tery cable, removing fuse or disconnecting ECM con-
nectors)
When the same malfunction (DTC) is not detected
again during 40 engine warm-up cycles.
Ambient temperature Time to cut power to ECM
Over 0 °C (32 °F) 30 sec. or longer
Under 0 °C (32 °F)Not specifiable.
Select a place with higher than
0 °C (32 °F) temperature.
Downloaded from www.Manualslib.com manuals search engine 6-42 ENGINE GENERAL INFORMATION AND DIAGNOSIS
Component Location
NOTE:
The figure shows left-hand steering vehicle.
For right-hand steering vehicle, parts with (*) are installed at the other side.
1. IAT sensor a : Immobilizer indicator lamp (if equipped) A : ECM
2. TP sensor b : A/C condenser fan motor relay (if equipped) B : A/T control module
3. Monitor connector c : Main relay C : EVAP canister
4. CO adjusting resistor (if equipped) d : Fuel pump relay D : DLC
5. CKP sensor e : IAC valve E : ABS control module (if equipped)
6. MAP sensor f : EVAP canister purge valve
7. CMP sensor g : EGR valve (if equipped)
8. Transmission range switch h : Fuel injector
9. VSS i : Ignition coil assemblies
10. HO2S-1 (if equipped) j : MIL
11. HO2S-2 (if equipped)
12. ECT sensor
13. Knock sensor
Downloaded from www.Manualslib.com manuals search engine ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-45
Table A-3 Malfunction Indicator Lamp Circuit Check - Mil Flashes at Ignition
Switch ON
WIRING DIAGRAM / CIRCUIT DESCRIPTION
Refer to table A-1.
INSPECTION
Table A-4 Malfunction Indicator Lamp Circuit Check - MIL Does Not Flash, Just
Remains ON or Just Remains OFF Even with Grounding Diagnosis Switch
Terminal
WIRING DIAGRAM / CIRCUIT DESCRIPTION
Refer to table A-1.
INSPECTION
Step Action Yes No
1 MIL flashing pattern check :
1) With the ignition switch ON position, check
MIL flashing pattern.
Does MIL flashing pattern indicate DTC (diag-
nostic trouble code)?Go to Step 2. Go to “Diagnosis” in Sec-
tion 8G.
2 Diagnosis switch terminal check :
1) With the ignition switch ON position, check
voltage between E18-14 terminal of ECM
coupler and ground.
Is voltage 4 – 5 V?Substitute a known-good
ECM and recheck.“W/Bl” wire (diagnosis
switch terminal) shorted
to ground circuit.
If OK, substitute a known-
good ECM and recheck.
Step Action Yes No
1 MIL flashing pattern check :
1) With grounding diagnosis switch terminal
and turn the ignition switch ON position,
check voltage between E18-14 terminal of
ECM connector and ground.
Is voltage 0 – 1 V?Go to Step 2.“W/Bl” wire (diagnosis
switch terminal), “B” wire
of monitor connector
open.
If OK, substitute a known-
good ECM and recheck.
2 Test switch terminal circuit check :
1) With the ignition switch ON position, check
voltage between E18-15 terminal of ECM
connector and ground.
Is voltage 4 – 5 V?Substitute a known-good
ECM and recheck.“P” wire (test switch termi-
nal) shorted to ground cir-
cuit.
If OK, substitute a known-
good ECM and recheck.
Downloaded from www.Manualslib.com manuals search engine 6-94 ENGINE GENERAL INFORMATION AND DIAGNOSIS
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.
Downloaded from www.Manualslib.com manuals search engine ENGINE AND EMISSION CONTROL SYSTEM 6E-5
Air Intake System
The main components of the air intake system are air cleaner (1), air cleaner outlet hose (2), throttle body (3),
idle air control valve (4) and intake manifold (5).
The air (by the amount corresponding to the throttle valve (6) opening and engine speed) is filtered by the air
cleaner (1), passes through the throttle body (3), is distributed by the intake manifold (5) and finally drawn into
each combustion chamber.
When the idle air control valve (4) is opened according to the signal from ECM, the air (7) bypasses the throttle
valve (6) through bypass passage and is finally drawn into the intake manifold (5).
1. Air Cleaner 17. Knock sensor 31-2. Test switch terminal
(vehicle w/o immobilizer indicator lamp)
2. EVAP canister purge valve 18. ECT sensor 31-3. Duty output terminal
(vehicle w/o immobilizer indicator lamp)
3. IAT sensor 19. CMP sensor 32. Immobilizer indicator lamp (if equipped)
4. TP sensor 20. CKP sensor 33. Stop lamp switch
5. IAC valve 21. VSS 34. ECM
6. MAP sensor 22. A/C condenser fan (if equipped) 35. Barometric pressure sensor
(vehicle with immobilizer indicator lamp)
7. EGR valve (if equipped) 23. Malfunction indicator lamp in combination meter 36. Battery
8. EVAP canister 24. Park/Neutral position switch in TR switch (A/T) 37. Immobilizer control module (if equipped)
9. Tank pressure control valve (built-in fuel pump) 25. Ignition switch 38. ABS control module (if equipped)
10. Fuel pump 26. Starter magnetic switch 39. CO adjusting resistor (if equipped)
11. Fuel level sensor 27. TCM (A/T) 40. Power steering pressure switch
(if equipped)
12. Ignition coil assembly 28. Transmission range switch (A/T) 41. A/C compressor clutch (if equipped)
13. Fuel injector 29. DLC 42. A/C EVAP TEMP. sensor (if equipped)
14. Heated Oxygen Sensor (HO2S)-1 (if equipped) 30. Electric load 43. A/C switch (if equipped)
15. Heated Oxygen Sensor (HO2S)-2 (if equipped) 31. Monitor connector (if equipped)
16. Three way catalytic convertor (if equipped) 31-1. Diagnosis switch terminal
(vehicle w/o immobilizer indicator lamp)
Downloaded from www.Manualslib.com manuals search engine ENGINE AND EMISSION CONTROL SYSTEM 6E-7
Electronic Control System
The electronic control system consists of 1) various sensors which detect the state of engine and driving condi-
tions, 2) ECM which controls various devices according to the signals from the sensors and 3) various controlled
devices.
Functionally, it is divided into the following sub systems:
Fuel injection control system
Idle speed control system
Fuel pump control system
A/C control system (if equipped)
A/C condenser fan control system
EGR system (if equipped)
Evaporative emission control system
Oxygen sensor heater control system
Ignition control system
Also, with A/T model, ECM sends throttle valve opening signal and over drive cut signal to transmission control
module to control A/T.
NOTE:
The figure shows left-hand steering vehicle. For right-hand steering vehicle, parts with (*) are installed
at the other side.
1. IAT sensor a : Immobilizer indicator lamp (if equipped) A : ECM
2. TP sensor b : A/C condenser fan motor relay (if equipped) B : A/T control module
3. Monitor connector c : Main relay C : EVAP canister
4. CO adjusting resistor (if equipped) d : Fuel pump relay D : DLC
5. CKP sensor e : IAC valve E : ABS control module (if equipped)
6. MAP sensor f : EVAP canister purge valve
7. CMP sensor g : EGR valve (if equipped)
8. Transmission range switch h : Fuel injector
9. VSS i : Ignition coil assemblies
10. HO2S-1 (if equipped) J : MIL
11. HO2S-2 (if equipped)
12. ECT sensor
13. Knock sensor