2002 SUZUKI GRAND VITARA check engine light

YH4
GRAND
VITARA
G16 / J20 Engines
H25 Engine
1. PCM
2. J / B
3. O / D cut switch
4. P / N change switch
5. J / C
1. PCM
2. Fuse
3. O / D cut switch
4. P / N change switch
5. J / C
6. J / C
AUTOMATIC TRANSMISSION (4 A / T) 7B1-37
DIAGNOSTIC FLOW TABLE B-3 ªPOWERº LIGHT CIRCUIT CHECK
(ªPOWERº LIGHT DOESN'T LIGHT AT IGNITION SWITCH ON BUT
ENGINE STARTS UP)
WIRING DIAGRAM
TROUBLESHOOTING
STEPACTIONYESNO
1ªPOWERº light circuit check:
(1) With ignition switch OFF, disconnect
couplers from PCM.
(2) Using service wire, connect E61-21 (G16 /
J20 engines) or E61-10 (H25 engine)
terminal of disconnected PCM coupler and
ground.
Does ªPOWERº light turn ON at ignition switch
ON?Poor E61-21 (G16 / J20
engines) or E61-10 (H25
engine) terminal
connection.
If OK, substitute a known-
good PCM and recheck.Bulb burned out or faulty
ªGr / Blº, ªB / Wº wire.

YH4
GRAND
VITARA
7B1-38 AUTOMATIC TRANSMISSION (4 A / T)
ª5º
ª4º
DIAGNOSTIC FLOW TABLE B-4 ªPOWERº LIGHT CIRCUIT CHECK
(ªPOWERº LIGHT COMES ON STEADILY)
WIRING DIAGRAM ± Refer to Table B-3 in this section.
TROUBLESHOOTING
STEPACTIONYESNO
1Check Power / Normal Change Switch Position.
Is switch button at Normal position?Go to Step 2.Set Power / Normal
change switch at
Normal position.
2Check Lamp Circuit for Short.
1) Turn ignition switch OFF and disconnect PCM
connectors.
2) Turn ignition switch ON.
Does ªPOWERº lamp come ON steadily?ªGr / Blº circuit
shorted to ground.Go to Step 3.
3Check Power / Normal Change Switch Circuit.
1) Check resistance between terminal E61-31
(G16/J20 engines) or E61-9 (H25 engine) of
disconnected PCM connector and body ground with
P / N change switch OFF.
Is continuity indicated?Go to Step 4.Check PCM ground
circuit for open.
If ground circuit is
OK, substitute a
known-good PCM
and recheck.
4Check Power / Normal Change Switch for Operation.
1) Remove Power / Normal change switch.
2) Check continuity between switch terminals ª4º and
ª5º under each condition below.
Normal position: No continuity
Power position: Continuity.
Is check result satisfactory?ªOr / Blº circuit
shorted to ground.Replace Power /
Normal change
switch.
Fig. for Step 1. Fig. for Step 4.

YH4
GRAND
VITARA
7B1-64 AUTOMATIC TRANSMISSION (4 A / T)
1. A / T vehicle (output) speed sensor
ªNº reference
line
Center line on
manual valve shaft
G16 / J20
1. Service wire
2. PCM connectors disconnected
Switch
position
TRANSMISSION RANGE SWITCH (SENSOR)
INSPECTION & ADJUSTMENT
1) Shift select lever to ªNº range.
2) Check that center line on manual valve shaft and ªNº reference
line on switch are aligned. If not, loosen switch bolt and align
them.
3) Check that engine starts in ªNº and ªPº ranges but it doesn't start
in ªDº, ª2º, ªLº or ªRº range. Also, check that back-up lamp lights
in ªRº range.
4) If faulty condition cannot be corrected by adjustment, discon-
nect transmission range switch coupler and check that continu-
ity exists as shown by moving select lever.
Terminal No.54982310765498231076
P
R
N
D
2
L
A / T OUTPUT SPEED SENSOR
INSPECTION
Check A / T output speed sensor for resistance between terminals
of sensor or PCM coupler.
A / T output speed sensor
resistance value : 387 ± 473
at 20
C, 68
F
O / D CUT SWITCH
INSPECTION
Check O / D cut switch for operation referring to step 4 of Diag. Flow
Table B-2 in this section.
If malfunction is found, replace.
SOLENOID VALVES
(Shift solenoid valves & TCC solenoid valve)
INSPECTION
With couplers of PCM disconnected and using service wire as
shown at the left, check each solenoid valve for clicking sound.
G16 / J20 Engines
Shift solenoid valve - A (#1)C51-1-2
Shift solenoid valve - B (#2)C51-1-1
TCC (Lock-up) solenoid valveC51-1-8

YH4
GRAND
VITARA
7E-6 DIFFERENTIAL (FRONT)
STEPACTIONYESNO
1Turn ON ignition switch (but engine at stop) and
check malfunction indicator lamp.
Does lamp light up?Go to step 2.A trouble has
occurred at some
place. Repair it
referring to
MALFUNCTION
INDICATOR LAMP
(ªCHECK ENGINEº
LAMP) CHECK in
DIAGNOSIS of
SECTION 6.
2Check 4WD switch circuit.
Turn ignition switch ON and check that voltage
between terminal C51-2-18 and terminal C51-3-17
(ground) for G16 / J20 (terminal C51-1-11 and terminal
C51-3-26 (ground) for H25) is as follows.

When transfer shift lever is in N or 2H: 10 ± 14 V

When transfer shift lever is in 4L or 4H: 0 ± 1 V
Is the check result satisfactory?Go to step 3.Check 4WD switch
(refer to SECTION
7A), ªB / Orº and ªBº
circuits of 4WD
switch.
If OK, substitute a
known-good ECM
(PCM) and recheck.
3Check power supply.
1) Turn ignition switch ON.
2) Check voltage between C51-2-7 and C51-3-17
(ground) for G16 / J20 (C51-1-15 and C51-3-26
(ground) for H25). The check results should be as
follows.

When transfer shift lever is in N or 2H: 0 ± 1 V

When transfer shift lever is in 4L or 4H: 10 ± 14 V
Is the check result satisfactory?Go to step 4.Check ªRº circuit. If
it is OK, substitute a
known-good ECM
(PCM) and recheck.
4Check air pump assembly circuit.
1) Check for proper connection to air pump
assembly at all terminals.
2) Turn ignition switch ON.
3) Check voltage between C51-2-27 and C51-3-17
(ground) for G16 / J20 (C51-1-18 and C51-3-26
(ground) for H25). The check result should be as
follows.

When transfer shift lever is in 2H or N: 0 ± 1 V

When transfer shift lever is in 4L or 4H
(more than 4 seconds after shifted to 4L or 4H):
10 ± 14 V
Is the check result satisfactory?Go to step 5.Check air pump
assembly referring
to ªON-VEHICLE
SERVICEº, and then
ªPº circuit.
If OK, substitute a
known-good ECM
(PCM) and recheck.
5Check 4WD indicator lamp circuit.
1) Turn ignition switch ON.
2) Check voltage between E61-19 and C51-3-17
(ground) for G16 / J20 (C51-1-7 and C51-3-26
(ground) for H25). The check result should be as
follows.

When transfer shift lever is in 2H or N: 10 ± 14 V

When transfer shift lever is in 4L or 4H: 0 ± 1 V
Is the check result satisfactory?4WD control system
is in good condition.Check ªOr / Bº circuit
(including indicator
lamp and
combination meter).
If OK, substitute a
known-good ECM
(PCM) and recheck.

YH4
GRAND
VITARA
1. Tachometer
2. Speedometer
3. Fuel level meter
4. Water temperature meter
5. Turn signal pilot light (LH)
6. 4WD indicator (if equipped)
7. ABS warning light (if equipped)
8. Immobilizer warning light (if equipped)
9. CHECK ENGINE light
10. Turn signal pilot light (RH)11. AIR BAG warning light (if equipped)
12. O / D OFF light (A / T vehicle only)
13. Fasten seat belt light (if equipped)
14. High beam light
15. Oil pressure warning light
16. Charge warning light
17. Brake and parking brake warning light
18. POWER indicator light (A / T vehicle only)
19. Shift position indicator (A / T vehicle, if equipped)or
CHECK
ENGINEor
ABS
8C-2 INSTRUMENTATION / DRIVER INFORMATION
GENERAL DESCRIPTION
CAUTIONS IN SERVICING
Refer to Section 8.
SYMBOLS AND MARKS
Refer to Section 8.
WIRING COLOR SYMBOLS
Refer to Section 8.
ABBREVIATIONS
Refer to Section 8.
JOINT CONNECTOR
Refer to Section 8.
FUSE BOX AND RELAY
Refer to Section 8.
POWER SUPPLY DIAGRAM
Refer to Section 8.
COMBINATION METER

YH4
GRAND
VITARA
8C-4 INSTRUMENTATION / DRIVER INFORMATION
DIAGNOSIS
NOTE:
Fuse name (ª º) in the table below is shown on the fuse box cover (Hard Top Model) or the junction box
(Canvas Top Model).
SPEEDOMETER AND VSS
TroublePossible CauseCorrection
Speedometer shows no
operation
ªIG / METERº fuse blown (Hard Top
Model)
ªIGº fuse blown (Canvas Top Model)

VSS faulty

Printed plate in combination meter
faulty

Speedometer faulty

Wiring or grounding faultyReplace fuse to check for short
Replace VSS
Replace printed plate
Replace speedometer
Repair
FUEL METER / FUEL GAUGE UNIT
TroublePossible CauseCorrection
Fuel meter shows no
operation
ªIG / METERº fuse blown (Hard Top
Model)
ªIGº fuse blown (Canvas Top Model)

Fuel gauge unit faulty

Printed plate in combination meter
faulty

Fuel meter faulty

Wiring or grounding faultyReplace fuse to check for short
Replace fuel gauge unit
Replace printed plate
Replace fuel meter
Repair
ENGINE COOLANT TEMP. (ECT) METER AND SENSOR
TroublePossible CauseCorrection
Engine coolant temp.
meter shows no operation
ªIG / METERº fuse blown (Hard Top
Model)
ªIGº fuse blown (Canvas Top Model)

ECT meter faulty

Printed plate in combination meter
faulty

ECT sensor faulty

Wiring or grounding faultyReplace fuse to check for short
Replace ECT meter
Replace printed plate
Replace ECT sensor
Repair
OIL PRESSURE LIGHT
TroublePossible CauseCorrection
Oil pressure warning light
does not light up
Bulb in combination meter blown

ªIG / METERº fuse blown (Hard Top
Model)
ªIGº fuse blown (Canvas Top Model)

Printed plate in combination meter
faulty

Oil pressure switch faulty

Wiring or grounding faultyReplace bulb
Replace fuse to check for short
Replace printed plate
Replace oil pressure switch
Repair

YH4
GRAND
VITARA
8C-10 INSTRUMENTATION / DRIVER INFORMATION
G16
J20
H25
1. ECT sensor
1
ENGINE COOLANT TEMP. (ECT) METER AND
SENSOR
ENGINE COOLANT TEMPERATURE (ECT) METER
INSPECTION
1) Disconnect Y/W lead wire going to ECT sensor.
2) Turn ignition switch ON, and check that ECT meter indicates
COOL.
3) Turn ignition switch OFF.
4) Ground Y/W lead wire through a 3.4 W test bulb (1) as illustrated.
5) Turn ignition switch ON, and check that bulb light up and pointer
(2) moves to hot side.
6) If ECT meter shows no operation, repair or replace defective
parts.
ENGINE COOLANT TEMPERATURE (ECT) SENSOR
REMOVAL AND INSTALLATION
Refer to ECT SENSOR in ON-VEHICLE SERVICE in Section 6E1
(for G16 and J20) or Section 6E2 (for H25) of this manual for details.

YH4
GRAND
VITARA
G16
J20
H25
1. Oil pressure switch
INSTRUMENTATION / DRIVER INFORMATION 8C-11
INSPECTION
1) Warm up ECT sensor (1) observing resistance between sensor
terminal (2) and sensor unit (1). Resistance should be de-
creased with increase of its temperature.
2) Check resistance between sensor terminal (2) and sensor unit
(1) shown below. If check result is not as specified, replace sen-
sor.
Temperature
Resistance
50
C (122
F)136 ± 216

OIL PRESSURE LIGHT
OIL PRESSURE SWITCH
REMOVAL AND INSTALLATION
Refer to OIL PRESSURE CHECK in Section 6A1 (for G16), Section
6A2 (for H25), and Section 6A4 (for J20) of this manual for details.
INSPECTION
1) Disconnect oil pressure switch (1) lead wire.
2) Check for continuity between oil pressure switch terminal (2)
and cylinder block (3) as shown.
During Engine Running
No continuity
At Engine StopContinuity
If check result is not as specified, replace oil pressure switch (1).