2001 SUZUKI GRAND VITARA Power

6-1-40 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
C51-1-10A/T input speed sensor (–)
(A/T vehicle)About 2.5 V Ignition switch ON
C51-1-11A/T input speed sensor (+)
(A/T vehicle)About 2.5 V Ignition switch ON
C51-1-12 Camshaft position sensor 1Deflects between
0 – 1 V and 4 – 6 VIgnition switch ON, crankshaft
turned slowly
C51-1-13 Camshaft position sensor 2Deflects between
0 – 1 V and 4 – 6 VIgnition switch ON, crankshaft
turned slowly
C51-1-14 Vehicle speed sensorDeflects between
0 – 1 V and over 4VIgnition switch ON, Rear right tire
turned slowly with rear left tire
locked
C51-1-15 EVAP canister purge valve 10 – 14 V Ignition switch ON
C51-1-16 IAC valve (stepper motor coil 4) – –
C51-1-17 IAC valve (stepper motor coil 3) – –
C51-1-18Transmission range switch “D”
(A/T vehicle)10 – 14 VIgnition switch ON, selector lever :
“D” range
0 – 1 VIgnition switch ON, selector lever :
Other than “D” range
C51-1-19Transmission range switch “N”
(A/T vehicle)10 – 14 VIgnition switch ON, selector lever :
“N” range
0 – 1 VIgnition switch ON, selector lever :
Other than “N” range
C51-1-20Shield wire ground for A/T output
speed sensor (A/T vehicle)––
C51-1-21Shield wire ground for A/T input
speed sensor (A/T vehicle)––
C51-1-22A/T output speed sensor (–)
(A/T vehicle)About 2.5 V Ignition switch ON
C51-1-23A/T output speed sensor (+)
(A/T vehicle)About 2.5 V Ignition switch ON
C51-1-24 Engine start signal10 – 14 V While engine cranking
0 – 1 V Other than above
C51-1-25 Power steering pressure switch10 – 14 V Ignition switch ON
0 – 1 VWith engine running at idle speed,
turning steering wheel to the right or
left as far as it stops
C51-1-26 4WD low switch0 – 1 VIgnition switch ON, Transfer lever :
4WD low range
10 – 14 VIgnition switch ON, Transfer lever :
4H or 2H range
C51-1-27Transmission range switch “L”
(A/T vehicle)10 – 14 VIgnition switch ON, selector lever :
“L” range
0 – 1 VIgnition switch ON, selector lever :
Other than “L” range
C51-1-28Transmission range switch “2”
(A/T vehicle)10 – 14 VIgnition switch ON, selector lever :
“2” range
0 – 1 VIgnition switch ON, selector lever :
Other than “2” range TERMINAL CIRCUIT NORMAL VOLTAGE CONDITION

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-43
Table A-1 Malfunction Indicator Lamp Circuit Check – Lamp Does Not Come
“ON” or Dims at Ignition Switch ON (But Engine at Stop)
WIRING DIAGRAM
CIRCUIT DESCRIPTION
When the ignition switch is turned ON, ECM causes the main relay to turn ON (close the contact point). Then,
ECM being supplied with the main power, turns ON the malfunction indicator lamp (MIL). When the engine
starts to run and no malfunction is detected in the system, MIL goes OFF but if a malfunction was or is detected,
MIL remains ON even when the engine is running.
INSPECTION
1. MIL
2. To ignition switch
3. Main fuse
4. Main relay
5. ECM (PCM)
6. Monitor connector (if equipped)
Step Action Yes No
1 MIL power supply check :
1) Turn ignition switch ON.
Do other indicator/warning lights in combination
meter comes ON?Go to Step 2. “IG METER” fuse blown,
main fuse blown, Ignition
switch malfunction, “BLK/
WHT” circuit between “IG
METER” fuse and combi-
nation meter or poor cou-
pler connection at
combination meter.

6-1-44 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
Table A-2 Malfunction Indicator Lamp Circuit Check – Lamp Remains “ON”
after Engine Starts
WIRING DIAGRAM/CIRCUIT DESCRIPTION
Refer to TABLE A-1.
INSPECTION
2 ECM power and ground circuit check :
Does engine start?Go to Step 3. Go to “TABLE A-3 ECM
(PCM) POWER AND
GROUND CIRCUIT
CHECK” in this section.
If engine is not cranked,
go to “DIAGNOSIS” in
Section 6G.
3 MIL circuit check :
1) Turn ignition switch OFF and disconnect
connectors from ECM.
2) Check for proper connection to ECM at ter-
minal E61-7.
3) If OK, then using service wire, ground termi-
nal E61-7 in connector disconnected.
Does MIL turn on at ignition switch ON?Substitute a known-good
ECM (PCM) and recheck.Bulb burned out or “PPL/
YEL” wire circuit open. Step Action Yes No
Step Action Yes No
1 DTC check :
1) With ignition switch OFF, install scan tool.
2) Start engine and check DTC.
Is there any malfunction DTC (s).Go to Step 2 of “ENGINE
DIAG. FLOW TABLE” in
this section.Go to Step 2.
2 MIL circuit check :
1) With ignition switch OFF, disconnect cou-
plers from ECM (PCM).
Does MIL turn ON at ignition switch ON?“PPL/YEL” wire shorted to
ground circuit.Substitute a known-good
ECM (PCM) and recheck.

6-1-46 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
Table A-5 ECM (PCM) Power and Ground Circuit Check – MIL Doesn’t Light at
Ignition Switch ON and Engine Doesn’t Start Though It Is Cranked Up
WIRING DIAGRAM
CIRCUIT DESCRIPTION
When the ignition switch is turned ON, the main relay turns ON (the contact point closes) and the main power is
supplied to ECM (PCM).
1. MIL
2. To ignition switch
3. Main fuse
4. Main relay
5. ECM (PCM)

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-47
INSPECTION
Step Action Yes No
1 Main relay operating sound check :
Is operating sound of main relay heard at igni-
tion switch ON?Go to Step 5. Go to Step 2.
2 Fuse check :
Is main “FI” fuse in good condition?Go to Step 3. Check for short in circuits
connected to this fuse.
3 Main relay check :
1) Turn OFF ignition switch and remove main
relay.
2) Check for proper connection to main relay
at terminal 3 and 4.
3) If OK, check main relay for resistance and
operation referring to “MAIN RELAY
INSPECTION” in Section 6E2.
Is check result satisfactory?Go to Step 4. Replace main relay.
4 ECM (PCM) power circuit check :
1) Turn OFF ignition switch, disconnect con-
nectors from ECM (PCM) and install main
relay.
2) Check for proper connection to ECM (PCM)
at terminals C51-3-20, E61-9, C51-3-15 and
C51-3-4.
3) If OK, then measure voltage between termi-
nal C51-3-20 and ground, E61-9 and
ground with ignition switch ON.
Is each voltage 10 – 14 V?Go to Step 5. “BLK/WHT”, “BLU” or
“BLK/RED” circuit open.
5 ECM power circuit check :
1) Using service wire, ground terminal E61-9
and measure voltage between terminal
C51-3-15 and ground at ignition switch ON.
Is it 10 – 14 V?Check ground circuits
“BLK/GRN” and “BLK/
ORN” for open.
If OK, then substitute a
known-good ECM (PCM)
and recheck.Go to Step 6.
6 Is operating sound of main relay heard in Step
1?Go to Step 7. “BLK/RED” or “BLU/BLK”
wire open.
7 Main relay check :
1) Check main relay according to procedure in
Step 3.
Is main relay in good condition?“BLK/RED” or “BLU/BLK”
wire open.Replace main relay.

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-49
DTC CONFIRMATION PROCEDURE
1) Connect scan tool to DLC 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 20 sec. or more.
3) Check DTC by using scan tool.
TROUBLESHOOTING
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 person, a driver and a tester, on a level road.
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 MAF sensor check :
1) Connect scan tool to DLC with ignition
switch OFF.
2) Start engine and check MAF value dis-
played on scan tool. (Refer to “SCAN TOOL
DATA” in this section for normal value.)
Is normal value indicated?Intermittent trouble.
Check for intermittent
referring to “INTERMIT-
TENT AND POOR CON-
NECTION” in Section 0A.Go to Step 3.
3 MAF sensor power supply check :
1) With ignition switch OFF, disconnect MAF
sensor coupler.
2) With ignition switch ON, check voltage
between E154-3 of MAF sensor coupler and
ground.
Is voltage 10 – 14 V?Go to Step 4. Faulty “BLU/BLK” wire.
4 MAF sensor output voltage check :
1) With ignition switch OFF, connect MAF sen-
sor coupler.
2) Remove ECM (PCM) cover.
3) With ignition switch ON leaving engine OFF,
check voltage between C51-3-10 and C51-
3-5 terminal.
Is voltage 1.0 – 1.6 V?Poor C51-3-10 or/C51-3-5
terminal connection.
If OK, substitute a known-
good ECM (PCM) and
recheck.Faulty “PPL/WHT” wire.
Poor E154 coupler termi-
nal connection.
If wire and connection are
OK, substitute a known-
good MAF sensor and
recheck.

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-55
TROUBLESHOOTING
Step Action Yes No
1 Was “ENGINE DIAG. FLOW TABLE” per-
formed?Go to Step 2. Go to “ENGINE DIAG.
FLOW TABLE”.
2 Check TP sensor and its circuit.
1) Connect scan tool to DLC with ignition
switch OFF and then turn ignition switch
ON.
2) Check throttle valve opening percentage
displayed on scan tool.
Is it displayed 3% or less?
3) Check throttle valve opening percentage
displayed on scan tool while opening throttle
valve from idle position to full open position.
Is it displayed 96% or higher?Go to Step 3. Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection” in
Section 0A.
3 Check wire harness.
1) Disconnect connector from TP sensor with
ignition switch OFF.
2) Check for proper connection to TP sensor at
“GRY/RED”, “RED/GRN” and “GRY/YEL”
wire terminal.
3) If OK, then with ignition switch ON, check
voltage between each of “GRY/RED” or
“RED/GRN” wire terminals and body
ground.
Is voltage about 4 – 6 V at each terminal?Go to Step 4. “GRY/RED” wire open,
“GRY/RED” wire shorted
to ground circuit or power
circuit or “RED/GRN”
wire, “GRY/YEL” wire
open or shorted to ground
circuit or poor C51-3-13 or
C51-3-9 connection.
If wire and connection are
OK, substitute a known-
good ECM and recheck.
4 Check TP sensor.
1) Check resistance between terminals of TP
sensor referring to “TP SENSOR” in Section
6E2.
Are measured values within specifications?“RED/GRN” wire shorted
to power circuit.
If wire is OK, substitute a
known-good ECM (PCM)
and recheck.Replace TP sensor.

6-1-58 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
DTC P0130 (DTC No.13) HO2S-1 (Bank 1) 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-1)
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)