2001 SUZUKI GRAND VITARA fuel relay

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-63
DTC P0136 HO2S-2 (Bank 1) Circuit Malfunction
WIRING DIAGRAM
DTC DETECTING CONDITION AND TROUBLE AREA
DTC CONFIRMATION PROCEDURE
1. HO2S heater relay
2. ECM (PCM)
3. HO2S-2 (Bank-1)
DTC DETECTING CONDITION TROUBLE AREA
DTC will set when any one of following conditions is detected (2 driving
cycle detection logic).
• 4.5 V or more HO2S circuit voltage is detected when 5 V power is con-
nected to HO2S circuit in ECM (PCM).
• While running with A/F feed back, average output voltage during speci-
fied time is too high or too low.
or
• While running with A/F feed back, max output voltage during specified
time is lower than specified value or min. output voltage during speci-
fied time is higher than specified value.• HO2S-2 or its circuit
• Fuel system
•ECM (PCM)
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, on a level road.

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-67
DTC P0150 (DTC No.26) HO2S-1 (Bank 2) Circuit Malfunction or No Activity
Detected
WIRING DIAGRAM
DTC DETECTING CONDITION AND TROUBLE AREA
1. HO2S heater relay
2. ECM (PCM)
3. HO2S-1 (Bank-2)
NOTE:
For vehicle with monitor connector, DTC will set when following only (*) mark condition is detected.
DTC DETECTING CONDITION TROUBLE AREA
Any one of the following conditions are detected in idle state while running
under driving conditions described for “DTC CONFIRMATION PROCEDURE”.
• 4.5 V or more HO2S circuit voltage is detected, when 5 V power is con-
nected to HO2S circuit in ECM (PCM), or
• Max. output voltage of HO2S is 0.6 V or lower on average and its minimum
voltage on average is 0.3 V or lower.
• Min. output voltage of HO2S is over 3.0 V or
• Max. output voltage of HO2S is 0.74 V or higher on average and its min.
voltage on average is 0.33 V or higher.
• Output voltage of HO2S-1 does not exceed 0.45 V for specified time.
(2 driving cycle detection logic)HO2S-1 or its circuit.
Fuel system
ECM (PCM)

6-1-72 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
DTC P0156 HO2S-2 (Bank 2) Circuit Malfunction
WIRING DIAGRAM
DTC DETECTING CONDITION AND TROUBLE AREA
DTC CONFIRMATION PROCEDURE
1. HO2S heater relay
2. ECM (PCM)
3. HO2S-2 (Bank-2)
DTC DETECTING CONDITION TROUBLE AREA
DTC will set when any one of following conditions is detected (2 driving
cycle detection logic).
• 4.5 V or more HO2S circuit voltage is detected when 5 V power is con-
nected to HO2S circuit in ECM (PCM).
• While running with A/F feed back, average output voltage during speci-
fied time is too high or too low.
or
• While running with A/F feed back, max output voltage during specified
time is lower than specified value or min. output voltage during speci-
fied time is higher than specified value.• HO2S-2 or its circuit
• Fuel system
• ECM (PCM)
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, on a level road.

6-1-116 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
Table B-1 Fuel Pump Circuit Inspection
WIRING DIAGRAM
INSPECTION
1. To ignition switch 4. Fuel pump relay
2. Main fuse 5. Fuel pump
3. Main relay 6. ECM (PCM)
CAUTION:
Check to make sure that connection is made between correct terminals.
Wrong connection can cause damage to ECM, wire harness etc.
Step Action Yes No
1 Fuel pump operation check :
1) Remove fuel filler cap.
2) Turn ON ignition switch.
Is fuel pump operation sound heard for 3 sec.
after ignition switch ON?Fuel pump circuit is in
good condition.Go to Step 2.
2 Fuel pump circuit check :
1) With ignition switch OFF, remove fuel pump
relay from connector.
2) Check for proper connection to relay at
each terminal.
3) If OK, using service wire, connect terminals
E07-7 and E07-8 of relay connector. (See
Fig.)
Is fuel pump heard to operate at ignition switch
ON?Go to Step 3.“BLU/BLK”, “PNK/BLK” or
“BLK” circuit open or fuel
pump malfunction.

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-117
Fig. for Step 2
Table B-2 Fuel Injectors and Circuit Inspection
WIRING DIAGRAM
3 Fuel pump relay check :
1) Check fuel pump relay referring to “FUEL
PUMP RELAY INSPECTION” in Section
6E2.
Is it in good condition?“BLK/WHT” or “WHT/
GRN” circuit open or poor
E61-23 connection.
If wire and connection are
OK, substitute a known-
good ECM (PCM) and
recheck.Replace fuel pump relay. Step Action Yes No
1. Fuel pump relay connector
1. To ignition switch 4. Injector No.1 7. Injector No.4 10. ECM (PCM)
2. Main fuse 5. Injector No.2 8. Injector No.5
3. Main relay 6. Injector No.3 9. Injector No.6

6E2-2 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
Fuel injector.......................................... 6E2-26
Electronic Control System........................ 6E2-31
Engine control module (ECM)/
powertrain control module (PCM) ........ 6E2-31
Mass air flow sensor (MAF sensor)...... 6E2-32
Intake air temperature (IAT) sensor ..... 6E2-34
Throttle position sensor (TP sensor) .... 6E2-35
Engine coolant temperature sensor
(ECT sensor) ........................................ 6E2-36
Heated oxygen sensor (sensor 1) ........ 6E2-37
Heated oxygen sensor (sensor 2) ........ 6E2-38
Vehicle speed sensor (VSS) ................ 6E2-39
Manifold absolute pressure sensor ...... 6E2-39
Fuel level sensor (sender gauge)......... 6E2-41
Crankshaft position sensor................... 6E2-41Main relay ............................................ 6E2-41
Fuel pump relay ................................... 6E2-42
Fuel cut operation ................................ 6E2-43
Emission Control System......................... 6E2-44
EGR system (if equipped) .................... 6E2-44
EVAP canister ...................................... 6E2-45
Vacuum passage ................................. 6E2-46
PCV System ............................................ 6E2-47
PCV hose ............................................. 6E2-47
PCV valve ............................................ 6E2-47
PCV system ......................................... 6E2-48
Tightening Torque Specification.............. 6E2-48
Special Tool ............................................... 6E2-48

General Description
The engine and emission control system has 4 major sub-systems: air intake system, fuel delivery system, elec-
tronic control system and emission control system.
Air intake system includes air cleaner, mass air flow sensor, throttle body, idle air control valve and intake man-
ifold.
Fuel delivery system includes fuel pump, delivery pipe, fuel pressure regulator, fuel injectors, etc.
Electronic control system includes ECM (PCM), various sensors and controlled devices.
Emission control system includes EGR, EVAP and PCV systems.

ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE) 6E2-5
1. Air cleaner 22. Fuel level sensor 39. A/C controller (if equipped)
2. Intake air temp. sensor 23. Monitor connector (if equipped) 40. Data link connector/Immobilizer control mod-
ule (if equipped)
3. Mass air flow sensor 23-1. Diag. switch terminal 41. ABS control module
4. EVAP canister purge valve 23-2. Test switch terminal 42. Main relay
5. Throttle position sensor 23-3. Output duty select switch terminal 43. Ignition switch
6. Idle air control valve 23-4. Duty output terminal 44. Park/Neutral position switch in TR switch (A/T)
7. Camshaft position sensor 24. Fuel filter 45. Battery
8. EGR valve 25. Fuel pressure regulator 46. Starter magnetic switch
9. Manifold absolute pressure sensor
(if equipped)26. Immobilizer indicator lamp (if equipped) 47.“O/D OFF” lamp (A/T)
10. Fuel injector 27. Tank pressure control valve 48.“POWER” lamp (A/T)
11. PCV valve 28. EVAP canister 49. Lighting switch (A/T)
12. Ignition coil assembly 29. Knock sensor 50. Stop lamp switch (A/T)
13. Engine coolant temperature sensor 30. ECM/PCM (Engine control module/Powertrain con-
trol module)51. O/D cut switch (A/T)
14. Heated oxygen sensor
(bank 1 sensor 1) (if equipped)31. Malfunction indicator lamp 52. POWER/NORMAL change switch (A/T)
15. Heated oxygen sensor
(bank 2 sensor 1) (if equipped)32. Electric loads (rear defogger (if equipped), lighting) 53. 4WD low switch (A/T)
16. Heated oxygen sensor
(bank 1 sensor 2) (if equipped)33. Power steering pressure switch 54. Transmission range switch (A/T)
17. Heated oxygen sensor
(bank 2 sensor 2) (if equipped)34. Heater blower fan switch 55. Solenoid valve A (A/T)
18. Warm-up three way catalytic converter
(if equipped)35. Cruise control module 56. Solenoid valve B (A/T)
19. Three way catalytic converter
(if equipped)36. Vehicle speed sensor 57. TCC solenoid valve (A/T)
20. Crankshaft position sensor
(if equipped)37. Combination meter 58. A/T input speed sensor (A/T)
21. Fuel pump 38. A/C condenser fan relay (if equipped) 59. A/T vehicle (output) speed sensor (A/T)

6E2-8 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
Electronic Control System
The electronic control system consists of 1) various sensors which detect the state of engine and driving condi-
tions, 2) ECM (PCM) 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
•Heated oxygen sensor heater control system (if equipped)
•Idle air control system
•Fuel pump control system
•Evaporative emission control system
•Ignition control system
•EGR system (if equipped)
Also, with A/T model, PCM controls A/T.
INFORMATION SENSORS CONTROLLED DEVICES OTHERS
1. IAT sensor a : A/C condenser fan motor relay (if equipped) A : Main fuse box
2. MAP sensor (if equipped) b : Ignition coil assemblies B : ECM (PCM)
3. Heated oxygen sensor (sensor 1) (if equipped) c : EVAP canister purge valve C : Data link connector
4. ECT sensor d : EGR valve (if equipped) D : Combination meter
5. TP sensor e : Idle air control valve E : Fuse box
6. MAF sensor f : Injectors F : EVAP canister
7. Camshaft position sensor (CMP sensor) g : Malfunction indicator lamp
8. ABS control module h : Fuel pump relay
9. Crankshaft position sensor (CKP sensor) (if equipped) i : Main relay
10. Power steering pressure switch (PSP switch) j : Oxygen sensor heater relay (if equipped)
11. CO adjusting resistor (if equipped)
12. Monitor connector (if equipped)
13. Transmission range switch (A/T)
14. Knock sensor
NOTE:
Above figure shows left-hand steering vehicle. For right-hand steering vehicle, parts with (*) are
installed at the side of symmetry.