2001 SUZUKI GRAND VITARA Power

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-61
DTC P0135 HO2S-1 (Bank 1) Heater Circuit Malfunction
WIRING DIAGRAM
Refer to DTC P0130.
DTC DETECTING CONDITION AND TROUBLE AREA
DTC CONFIRMATION PROCEDURE
1) Connect scan tool with ignition switch OFF.
2) Turn ON ignition switch and clear DTC, pending DTC and freeze frame data by using scan tool and run
engine at idle speed for 5 min.
3) Check pending DTC by using scan tool.
TROUBLESHOOTING
DTC DETECTING CONDITION TROUBLE AREA
Following condition is detected when HO2S heater is
electrically live (2 driving cycle detection logic).
• Current of HO2S heater is 5.3 A or more or less than
0.09 A, or
• Voltage of HO2S heater is 14.0 V or higher or lower
than 11.7 V.HO2S-1 heater circuit
HO2S-1 heater
ECM (PCM)
HO2S heater relay
NOTE:
Check to make sure that following conditions are satisfied when using this “DTC CONFIRMATION
PROCEDURE”.
Intake air temp. : – 8°C (18°F) or higher
Engine coolant temp. : – 8 – 110°C (18 – 230°F)
Altitude (barometric pressure) : 2400 m, 8000 ft or less (560 mmHg (75 kPa) or more)
Step Action Yes No
1 Was “ENGINE DIAG. FLOW TABLE” per-
formed?Go to Step 2. Go to “ENGINE
DIAG. FLOW TABLE” in
this section.
2 HO2S-1 heater check :
1) Disconnect HO2S-1 coupler with ignition
switch OFF.
2) Check resistance between “3” and “4” termi-
nal of HO2S-1 coupler.
HO2S-1 heater resistance :
5.0 – 6.4
Ω
ΩΩ Ω (at 20°C (68°F))
Is it within above specification?Go to Step 3. Replace HO2S-1.
3 HO2S heater power supply check :
1) With ignition switch ON leaving engine OFF,
check voltage between E139-3 and ground,
E139-1 and ground. (See Fig.)
Is each voltage 10 – 14 V?Go to Step 4. “HO2S”, and/or “IG
METER” fuse blown.
If OK, faulty “BLK/WHT”
wire or “BLU/WHT” wire.

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.

6-1-66 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
TROUBLESHOOTING
Fig. for STEP 2, 3Step Action Yes No
1 Was “ENGINE DIAG. FLOW TABLE” per-
formed?Go to Step 2. Go to “ENGINE DIAG.
FLOW TABLE” in this
section.
2 HO2S-2 heater check :
1) Disconnect HO2S-2 coupler with ignition
switch OFF.
2) Check resistance between “3” and “4” termi-
nal of HO2S-2 connector.
HO2S -2 heater resistance :
11.7 – 14.3
Ω
ΩΩ Ω (at 20°C (68°F))
Is it within above specificationGo to Step 3. Replace HO2S-2.
3 HO2S heater power supply check :
1) With ignition switch ON leaving engine OFF,
check voltage between E139-3 and ground,
E139-1 and ground. (See Fig.)
Is each voltage 10 – 14 V?Go to Step 4. Fuse “HO2S” and/or “IG
METER” blown.
If OK, faulty “BLK/WHT”
wire or “BLU/WHT” wire.
4 HO2S heater control circuit check :
1) With ignition switch OFF, install HO2S
heater relay.
2) With ignition switch ON leaving engine OFF,
check voltage between C51-2-16 and
ground.
Is the voltage 10 – 14 V?Substitute a known-good
ECM (PCM) and recheck.Faulty HO2S heater relay
or “BLK” wire open, “BLU”
wire open or shorted to
ground circuit, “WHT/
BLK” wire open or shorted
to ground circuit.
If OK, substitute a known-
good ECM (PCM) and
recheck.
a. HO2S heater relay

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)

6-1-70 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
DTC P0155 HO2S-1 (Bank 2) Heater Circuit Malfunction
WIRING DIAGRAM
Refer to DTC P0150.
DTC DETECTING CONDITION AND TROUBLE AREA
DTC CONFIRMATION PROCEDURE
1) Connect scan tool with ignition switch OFF.
2) Turn ON ignition switch and clear DTC, pending DTC and freeze frame data by using scan tool and run
engine at idle speed for 5 min.
3) Check pending DTC by using scan tool.
TROUBLESHOOTING
DTC DETECTING CONDITION TROUBLE AREA
Following condition is detected when HO2S heater is
electrically live (2 driving cycle detection logic).
• Current of HO2S heater is 5.3 A or more or less than
0.09 A, or
• Voltage of HO2S heater is 14.0 V or higher or lower
than 11.7 V.HO2S-1 heater circuit
HO2S-1 heater
ECM (PCM)
NOTE:
Check to make sure that following conditions are satisfied when using this “DTC CONFIRMATION
PROCEDURE”.
Intake air temp. : – 8°C (18°F) or higher
Engine coolant temp. : – 8 – 110°C (18 – 230°F)
Altitude (barometric pressure) : 2400 m, 8000 ft or less (560 mmHg (75 kPa) or more)
Step Action Yes No
1 Was “ENGINE DIAG. FLOW TABLE” per-
formed?Go to Step 2. Go to “ENGINE
DIAG. FLOW TABLE” in
this section.
2 HO2S-1 heater check :
1) Disconnect HO2S-1 coupler with ignition
switch OFF.
2) Check resistance between “3” and “4” termi-
nal of HO2S-1 coupler.
HO2S-1 heater resistance :
5.0 – 6.4
Ω
ΩΩ Ω (at 20°C (68°F))
Is it within above specification?Go to Step 3. Replace HO2S-1.
3 HO2S heater power supply check :
1) With ignition switch ON leaving engine OFF,
check voltage between E139-3 and ground,
E139-1 and ground. (See Fig.)
Is each voltage 10 – 14 V?Go to Step 4. “HO2S”, and/or “IG
METER” fuse blown.
If OK, faulty “BLK/WHT”
wire or “BLU/WHT” wire.

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.

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-75
TROUBLESHOOTING
Fig. for STEP 2, 3Step Action Yes No
1 Was “ENGINE DIAG. FLOW TABLE” per-
formed?Go to Step 2. Go to “ENGINE DIAG.
FLOW TABLE” in this
section.
2 HO2S-2 heater check :
1) Disconnect HO2S-2 coupler with ignition
switch OFF.
2) Check resistance between “3” and “4” termi-
nal of HO2S-2 connector.
HO2S -2 heater resistance :
11.7 – 14.3
Ω
ΩΩ Ω (at 20°C (68°F))
Is it within above specificationGo to Step 3. Replace HO2S-2.
3 HO2S heater power supply check :
1) With ignition switch ON leaving engine OFF,
check voltage between E139-3 and ground,
E139-1 and ground. (See Fig.)
Is each voltage 10 – 14 V?Go to Step 4. Fuse “HO2S” and/or “IG
METER” blown.
If OK, faulty “BLK/WHT”
wire or “BLU/WHT” wire.
4 HO2S heater control circuit check :
1) With ignition switch OFF, install HO2S
heater relay.
2) With ignition switch ON leaving engine OFF,
check voltage between C51-2-17 and
ground.
Is the voltage 10 – 14 V?Substitute a known-good
ECM (PCM) and recheck.Faulty HO2S heater relay
or “BLK” wire open, “BLU”
wire open or shorted to
ground circuit, “PNK/
WHT” wire open or
shorted to ground circuit.
If OK, substitute a known-
good ECM (PCM) and
recheck.
a. HO2S heater relay

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-83
TROUBLESHOOTING
Fig. for Steps 2 and 3Step Action Yes No
1 Was “ENGINE DIAG. FLOW TABLE” per-
formed?Go to Step 2. Go to “ENGINE DIAG.
FLOW TABLE” in this
section.
2 Knock sensor and its circuit check :
1) With engine running, check voltage from
“C51-3-3” terminal of ECM connector to
body ground. See Fig.
Is voltage about 0.90 – 3.98 V?Knock sensor and its cir-
cuit are in good condition.
Intermittent trouble or
faulty ECM.
Recheck, referring to
“INTERMITTENT TROU-
BLE” in Section 0A.Go to Step 3.
3 Knock sensor power source circuit check :
1) Stop engine.
2) With ignition switch at OFF position, discon-
nect knock sensor connector.
3) With ignition switch at ON position, check
voltage from “WHT” to body ground terminal
of knock sensor connector. See Fig.
Is it 4 – 5 V?Substitute a known-good
knock sensor and
recheck.“WHT” wire open, shorted
to ground circuit or poor
“C51-3-3” connection.
If wire and connection are
OK, substitute a known-
good substitute a known-
good ECM and recheck.
1. Knock sensor
2. Knock sensor connector