2001 SUZUKI GRAND VITARA engine start circuit

6-1-120 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
3 1) Start engine and warm it up to normal oper-
ating temperature.
2) Keep it running at specified idle speed.
Is fuel pressure then within 210 – 260 kPa
(2.1 – 2.6 kg/cm
2, 29.8 – 37.0 psi)?Normal fuel pressure. Clogged vacuum passage
for fuel pressure regula-
tor or faulty fuel pressure
regulator.
4 Is there fuel leakage from fuel feed line hose,
pipe or joint?Fuel leakage from hose,
pipe or joint.Go to Step 10.
5 Was fuel pressure higher than spec. in Step 1? Go to Step 6. Go to Step 7.
6 1) Disconnect fuel return hose from fuel pipe
and connect new hose to it.
2) Put the other end of new return hose into
approved gasoline container.
3) Operate fuel pump.
Is specified fuel pressure obtained then?Restricted fuel return
hose or pipe.Faulty fuel pressure regu-
lator.
7 Was no fuel pressure applied in Step 1? Go to Step 8. Go to Step 9.
(Low pressure is mea-
sured.)
8 With fuel pump operated and fuel return hose
blocked by pinching it, is fuel pressure applied?Faulty fuel pressure regu-
lator.Shortage of fuel or fuel
pump or its circuit defec-
tive (Refer to “TABLE B-
1”).
9 1) Operate fuel pump.
2) With fuel return hose blocked by pinching it,
check fuel pressure.
Is it 450 kPa (4.5 kg/cm
2, 64.0 psi) or more?Faulty fuel pressure regu-
lator.Clogged fuel filter,
restricted fuel feed hose
or pipe, faulty fuel pump
or fuel leakage from hose
connection in fuel tank.
10 1) Disconnect fuel return hose from fuel pipe
and connect new hose to it.
2) Put the other end of new return hose into
approved gasoline container.
3) Check again if specified fuel pressure is
retained.
While doing so, does fuel come out return
hose?Faulty fuel pressure regu-
lator.Fuel leakage from injec-
tor, faulty fuel pump
(faulty check valve in fuel
pump) or fuel leakage
from fuel pressure regula-
tor diaphragm. Step Action Yes No

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-123
Table B-5 A/C Signal Circuits Inspection (If Equipped)
WIRING DIAGRAM
INSPECTION
1. A/C control module (amplifier)
2. ECM (PCM)
Step Action Yes No
1 Check A/C Signal Circuit.
1) Check voltage at terminal E61-17 with ignition
switch ON.
A/C signal circuit specification :
A/C switch and/or heater blower switch OFF (A/
C is not operating) : 10 – 14 V
Both A/C switch and heater blower switch ON :
0 – 1.5 V
Are check result as specified?Go to Step 2.“YEL/BLK” circuit open or
short, Evaporative tem-
perature is below 1°C
(34°F) or faulty A/C sys-
tem.
2 Check A/C Cut Signal Circuit.
1) Check voltage at terminal E61-8.
A/C cut signal specification :
While engine running and A/C switch and/or
heater blower switch OFF
(A/C is not operating) : 0 – 1.5 V
While engine running at idle speed and both A/
C switch and heater blower switch ON
(A/C is operating) : 10 – 14 V
Are check result as specified?A/C control signal cir-
cuits are in good con-
dition.“GRY/WHT” circuit open
or short, Poor perfor-
mance of ECT sensor, TP
sensor, Engine start sig-
nal inputted or A/C ampli-
fier malfunction.
If none of the above
exists, substitute a
known-good ECM (PCM)
and recheck.

6-1-124 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
Table B-6 A/C Condenser Fan Motor Relay Control System Inspection (If
Equipped)
WIRING DIAGRAM
INSPECTION
1. To ignition switch 3. A/C fuse 5. A/C condenser fan motor
2. Main fuse 4. A/C condenser fan motor relay 6. ECM (PCM)
WARNING:
Keep hands, tools, and clothing away from A/C condenser fan to help prevent personal injury. This
fan is electric and can come on whether or not the engine is running. The fan can start automatically
in response to the ECT sensor with the ignition switch in the “ON” position.
Step Action Yes No
1 1) Check DTC referring to “DTC CHECK” in this sec-
tion.
Is there any malfunction DTC?Go to applicable DTC
Diag. Flow Table.Go to Step 2.
2 1) Check A/C condenser fan for operation.
A/C condenser fan should be operated under follow-
ing condition A or B only.
A : When engine is running and A/C is operating.
B : When engine coolant temp. is 113°C (235°F) or
more with ignition switch ON.
Is check result as specified?This system is in
good condition.Go to Step 3.
3 1) Remove ECM (PCM) cover.
2) Check voltage between E61-22 terminal of ECM
(PCM) connected coupler and ground.
Other than conditions A and B in Step 2 :
10 – 14 V
Under condition A or B in Step 2 :
0 – 1 V
Is check result as specified?Fuse blown, “RED”,
“RED/BLK” or “RED/
BLU” circuit open,
malfunction of con-
denser fan motor or
relay.“YEL/GRN” circuit
open, “YEL/BLU” cir-
cuit open or short, or
relay malfunction.
If above are OK, sub-
stitute a known-good
ECM (PCM) and
recheck.

6E2-10 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
TERMINAL ARRANGEMENT OF ECM (PCM) CONNECTOR (VIEWED FROM HARNESS SIDE)
1. Fuel injector No.1 17.“O/D OFF” lamp (A/T) 34. Power steering pressure switch
2. Fuel injector No.2 18.“POWER” lamp (A/T) 35. Stop lamp switch (Brake pedal switch)
3. Fuel injector No.3 18-1.“4WD” lamp (4WD) 36. Lighting switch
4. Fuel injector No.4 18-2. 4WD air pump assembly (4WD) 37. Rear defogger switch (if equipped)
4-1. Fuel injector No.5 19. 4WD switch (4WD) 38. Heater blower motor (if equipped)
4-2. Fuel injector No.6 20. Power/Normal change switch (A/T) 39. A/C control module (amplifier)
5. EGR valve (if equipped) 21. O/D cut switch (A/T) 40. ABS control module
6. Idle air control 21-1. 4WD low switch (4WD) 41. Heated oxygen sensor-1 (Bank1) (if equipped)
7. EVAP canister purge valve 22. Main relay 41-1. Heated oxygen sensor-1 (Bank2) (if equipped)
8. Ignition coil for No.1 23. Transmission range switch (Park/Neutral
Position Switch) or clutch pedal position switch42. Heater oxygen sensor-2 (Bank1) (if equipped)
8-1. Ignition coil for No.2 24. Starter magnetic switch 42-1. Heater oxygen sensor-2 (Bank2) (if equipped)
9. Ignition coil for No.3 24-1. Cruise control module (if equipped) 43. Intake air temp. sensor
9-1. Ignition coil for No.4 25. Vehicle speed sensor 44. Engine coolant temp. sensor
10. Ignition coil for No.5 26. Combination meter 45. Throttle position sensor
10-1. Ignition coil for No.6 27. Data link connector 46. CO adjusting resistor (if equipped)
11. Fuel pump relay 28. TCC solenoid (A/T) 47. Manifold absolute pressure sensor (if
equipped)
12. Fuel pump 29. Shift solenoid-B (A/T) 48. Mass air flow sensor
13. A/C condenser fan relay (if equipped) 30. Shift solenoid-A (A/T) 49. Camshaft position sensor
14. A/C condenser fan motor (if equipped) 31. Transmission range switch (sensor) (A/T) 50. Crankshaft position sensor (if equipped)
15. Knock sensor 32. A/T input speed sensor (A/T) 51. Monitor connector (if equipped)
16. Malfunction indicator lamp 33. A/T vehicle (output) speed sensor (A/T) 52. Engine control module
(Powertrain control module)
TERMINAL CIRCUIT TERMINAL CIRCUIT TERMINAL CIRCUIT
E61-1 Power source for CO adjusting resistor
(if equipped)E61-13 Data link connector E61-25—
E61-2 Power source for back up E61-14 Test switch terminal (if equipped) E61-26—
E61-3—E61-15 Rear defogger switch (if equipped) E61-27—
E61-4 Cruise control module
(Throttle opening signal)E61-16 Heater blower switch E61-28—
E61-5 Duty output terminal (if equipped) E61-17 A/C signal (if equipped) E61-29 Diag. switch terminal (if equipped)
E61-6 Tachometer E61-18—E61-30 ABS control module (if equipped)
E61-7 MIL (“SERVICE INGINE SOON” lamp) E61-19“4WD” lamp E61-31 Power/Normal change switch (A/T)
E61-8 A/C cut signal (if equipped) E61-20“O/D OFF” lamp (A/T) E61-32 Lighting switch
E61-9 Main relay E61-21“POWER” lamp (A/T) E61-33 O/D cut switch (A/T)
E61-10 CO adjusting resistor (if equipped) E61-22 A/C fan motor relay (if equipped) E61-34 Stop lamp switch (Brake pedal switch)
E61-11—E61-23 Fuel pump relay E61-35 Cruise control module (if equipped)
E61-12—E61-24 Ground for CO adjusting resistor (if
equipped)

ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE) 6E2-11
TERMINAL CIRCUIT TERMINAL CIRCUIT TERMINAL CIRCUIT
C51-3-1 Intake air temp. (IAT) sensor C51-3-13 Power source for TP sensor C51-3-25 Ground for IAT sensor, MAP sensor and
oxygen sensor (if equipped)
C51-3-2 Engine coolant temp. (ECT) sensor C51-3-14 Power source for MAP sensor (if
equipped)C51-3-26 Ground for CMP sensor
C51-3-3 Knock sensor C51-3-15 Power source
C51-3-4 Power source C51-3-16—
C51-3-5 Ground for MAF sensor C51-3-17 Ground
C51-3-6 Ground C51-3-18 Pressure switch in 4WD air pump
assembly
C51-3-7 4WD switch C51-3-19—
C51-3-8 Manifold absolute pressure (MAP)
sensor (if equipped)C51-3-20 Ignition switch
C51-3-9 Throttle position (TP) sensor C51-3-21 Heated oxygen sensor-1 (Bank2) (if
equipped)
C51-3-10 Mass air flow (MAF) sensor C51-3-22 Heated oxygen sensor-2 (Bank1) (if
equipped)
C51-3-11 Heated oxygen sensor-1 (Bank1) (if
equipped)C51-3-23 Heated oxygen sensor-2 (Bank2) (if
equipped)
C51-3-12 Ground for TP sensor C51-3-24 Ground for ECT sensor
TERMINAL CIRCUIT TERMINAL CIRCUIT TERMINAL CIRCUIT
C51-1-1 Shift solenoid-B (A/T) C51-1-13 CMP sensor C51-1-25 Power steering pressure switch
C51-1-2 Shift solenoid-A (A/T) C51-1-14 Vehicle speed sensor C51-1-26 4WD Low switch
C51-1-3—C51-1-15 EVAP canister purge valve C51-1-27 Transmission range switch “L” (A/T)
C51-1-4 IAC valve (stepper motor coil 2) C51-1-16 IAC valve (stepper motor coil 4) C51-1-28 Transmission range switch “2” (A/T)
C51-1-5 IAC valve (stepper motor coil 1) C51-1-17 IAC valve (stepper motor coil 3)
C51-1-6 Transmission range switch “R” (A/T) C51-1-18 Transmission range switch “D” (A/T)
C51-1-7 Transmission range switch “P” (A/T) C51-1-19 Transmission range switch “N” (A/T)
C51-1-8 TCC solenoid (A/T) C51-1-20 Shield wire ground for A/T output
speed sensor
C51-1-9 4WD air pump assembly C51-1-21 Shield wire ground for A/T input
speed sensor
C51-1-10 A/T input speed sensor (–) C51-1-22 A/T output speed sensor (–)
C51-1-11 A/T input speed sensor (+) C51-1-23 A/T output speed sensor (+)
C51-1-12 CMP sensor C51-1-24 Engine start signal
TERMINAL CIRCUIT TERMINAL CIRCUIT TERMINAL CIRCUIT
C51-2-1 Fuel injector No.2 C51-2-13 EGR valve (stepper motor coil 3) (if
equipped)C51-2-25 Ignition coil assembly for No.4
C51-2-2 Fuel injector No.1 C51-2-14 EGR valve (stepper motor coil 2) (if
equipped)C51-2-26 Ignition coil assembly for No.3
C51-2-3—C51-2-15 EGR valve (stepper motor coil 1) (if
equipped)C51-2-27 Ignition coil assembly for No.2
C51-2-4 Heater of HO2S-1 (Bank1) (if equipped) C51-2-16 Heater of HO2S-2 (Bank1) (if equipped) C51-2-28 Ignition coil assembly for No.1
C51-2-5 Heater of HO2S-1 (Bank2) (if equipped) C51-2-17 Heater of HO2S-2 (Bank2) (if equipped) C51-2-29—
C51-2-6—C51-2-18—C51-2-30 Ground for CKP sensor shield wire (if
equipped)
C51-2-7 Ground C51-2-19 CKP sensor (+) (if equipped)
C51-2-8 Fuel injector No.4 C51-2-20 CKP sensor (–) (if equipped)
C51-2-9 Fuel injector No.3 C51-2-21 Fuel injector No.6
C51-2-10—C51-2-22 Fuel injector No.5
C51-2-11—C51-2-23 Ignition coil assembly for No.6
C51-2-12 EGR valve (stepper motor coil 4) (if
equipped)C51-2-24 Ignition coil assembly for No.5

ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE) 6E2-15
Idle Speed/Idle Air Control (IAC) Duty Inspec-
tion
Before idle speed/IAC duty check, make sure of the following.
•Lead wires and hoses of engine/emission control systems
are connected securely.
•Accelerator cable is adjusted.
•Ignition timing is within specification.
•All accessories (wipers, heater, lights, A/C, etc.) are out of
service.
•Air cleaner has been properly installed and is in good condi-
tion.
•ECM (PCM) does not detect any malfunction DTC.
After above items are all confirmed, check idle speed and IAC
duty as follows.
[Using SUZUKI scan tool]
1) Connect SUZUKI scan tool to DLC with ignition switch OFF.
Special tool
(A) : SUZUKI scan tool
2) Warm up engine to normal operating temperature.
3) Check IAC duty and idle speed by using “Data List” mode of
SUZUKI scan tool.
Engine idle speed:
A/C OFF: 700 ± 50 r/min.
A/C ON: 750 ± 50 r/min.
IAC duty at specified idle speed:
5 – 40 % (at A/C OFF)
4) If duty and/or idle speed is out of specifications, check idle
air control system referring to “DIAG. FLOW TABLE B-4” in
Section 6-1.
5) Check that specified engine idle speed is obtained with A/C
ON if vehicle is equipped with A/C. If not, check A/C ON sig-
nal circuit and idle air control system. NOTE:
Before starting engine, place transmission gear shift
lever in “Neutral” (shift selector lever to “P” range for A/T
vehicle), and set parking brake and block drive wheels.

6E2-16 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
[Not using SUZUKI scan tool] (vehicle with monitor
connector)
1) Disconnect scan tool from DLC if connected.
2) Warm up engine to normal operating temperature.
3) Stop engine and connect duty meter (3) between duty output
terminal and ground terminal of monitor connector (1).
4) Using service wire (2), ground diagnosis switch terminal in
monitor connector.
5) Set tachometer.
6) Start engine and warm it up completely.
7) Check IAC duty and idle air control system referring to Diag-
nostic Flow Table B-4 “IDLE AIR CONTROL SYSTEM
CHECK” in this section.
•“OFF DUTY METER” is such duty meter that indicates
approx. 100% when terminal voltage is approx. “0 V”.
•“V
B” represents battery voltage while engine of vehicle being
checked is running.
8) Remove service wire from monitor connector.
9) Install cap to monitor connector.
10) Check that specified engine idle speed is obtained with A/C
ON if vehicle is equipped with A/C.
If not, check A/C ON signal circuit and idle air control sys-
tem.
A: Output duty select switch terminal
B: Diagnosis switch terminal
C: Blank
D: Ground terminal
E: Test switch terminal
F: Duty output terminal
A/C OFF A/C ON
Engine idle speed: 700 ± 50 r/min. 750 ± 50 r/min.
IAC duty at specified
idle speed:5 – 40 % (0.7 – 5.6 V
when battery voltage
is 14 V)–
NOTE:
IAC duty can be checked roughly by using voltmeter. I
AC duty to voltage relation is as follows.
ON DUTY METER
INDICATION
(%)OFF DUTY
INDICATION
(%)VOLT METER
INDICATION
(V)
0
50
10010
50
00
0.5 x V
B
VB

ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE) 6E2-37
Heated oxygen sensor (sensor 1)
REMOVAL
1) Disconnect negative (–) cable from battery.
2) Disconnect coupler of oxygen sensor (s).
3) Remove oxygen sensor (s) from exhaust manifold (s).
INSTALLATION
Reverse removal procedure noting the followings.
•Tighten oxygen sensor (s) to specified torque.
Tightening torque
Heated oxygen sensor 1
(a) : 45 N·m (4.5 kg-m, 32.5 lb-ft)
•Connect connector of oxygen sensor (s) and clamp wire har-
ness securely.
•After installing oxygen sensor (s), start engine and check
that no exhaust gas leakage exists.
INSPECTION
Inspect HO2S-1 and its circuit referring to “DTC P0130 or P0150
Diag. Flow Table” in Section 6-1. If malfunction is found, replace. WARNING:
To avoid danger of being burned, do not touch exhaust
system when system is hot. Oxygen sensor removal
should be performed when system is cool.
NOTE:
Be careful not to expose it to excessive shock.
1. Left (No.1) bank oxygen sensor (sensor 1)