
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 
![SUZUKI GRAND VITARA 1999 2.G Owners Manual ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-85
TROUBLESHOOTING
[A] Fig. for Step 3 / [B] Fig. for Step 4Step Action Yes No
1 Was “ENGINE DIAG. FLOW TABLE” performed? Go to Step 2. Go SUZUKI GRAND VITARA 1999 2.G Owners Manual ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-85
TROUBLESHOOTING
[A] Fig. for Step 3 / [B] Fig. for Step 4Step Action Yes No
1 Was “ENGINE DIAG. FLOW TABLE” performed? Go to Step 2. Go](/manual-img/20/7583/w960_7583-245.png)
ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-85
TROUBLESHOOTING
[A] Fig. for Step 3 / [B] Fig. for Step 4Step Action Yes No
1 Was “ENGINE DIAG. FLOW TABLE” performed? Go to Step 2. Go to “ENGINE DIAG. 
FLOW TABLE” in this 
section.
2 CKP sensor and its circuit resistance check :
1) With ignition switch OFF, disconnect ECM 
(PCM) coupler (C51-2).
2) Check for proper connection to ECM (PCM) at 
C51-2-19 and C51-2-20 terminals.
3) If OK, check resistance of followings.
CKP sensor resistance between C51-2-19 and 
C51-2-20 terminals :
484 – 656 
Ω
ΩΩ Ω at 20°C (68°F)
CKP sensor resistance between each terminal 
and ground :
1 M
Ω
ΩΩ Ω or more
Is check result satisfactory?Go to Step 4. Go to Step 3.
3 CKP sensor resistance check :
1) With ignition switch OFF, disconnect CKP sen-
sor coupler.
2) Check resistance between terminals of CKP 
sensor coupler. (See Fig.)
Were measured resistance values as specified in 
Step 2?Faulty “WHT/BLU” wire 
or “ORN/BLU” wire.Faulty CKP sensor.
4 CKP sensor visual inspection :
Check visually CKP sensor and signal rotor for the 
followings. (See Fig.)
• Damage
• No foreign material attached
• Correct installation
Are they in good condition?Intermittent trouble or 
faulty ECM (PCM). 
Recheck for intermit-
tent referring to 
“INTERMITTENT AND 
POOR CONNEC-
TION” in Section 0A.Replace or reinstall.
1. Sensor plate 

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-87
DTC DETECTING CONDITION AND TROUBLE AREA
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.
3) Crank engine for 3 seconds or more and keep it at idle for 1 min.
4) Check DTC by using scan tool.
TROUBLESHOOTING
DTC DETECTING CONDITION TROUBLE AREA
CMP sensor signal is not inputted for 3 sec. even though 
engine start signal is being inputted.
or
REF signal pattern is incorrect while POS signal varies.
or
POS signal voltage too high or too low.CMP sensor circuit
CMP sensor
Engine starter signal circuit
ECM (PCM)
NOTE:
Check to make sure that following condition is satisfied when using this “DTC CONFIRMATION PRO-
CEDURE”.
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)
NOTE:
If starter circuit is open (i.e., starter signal circuit is OK but starter fails to run), this DTC is stored in
memory at starter switch ON, even through CMP sensor is in good condition.
When starter motor fails to run and this DTC appears, check starter circuit first.
Step Action Yes No
1 Was “ENGINE DIAG. FLOW TABLE” performed? Go to Step 2. Go to “ENGINE DIAG. 
FLOW TABLE” in this 
section.
2 Is engine cranked? Go to Step 3. Go to Section 6G.
3 Is there DTC P1500 (Engine starter signal circuit)? Go to DTC P1500 Diag. 
Flow Table.Go to Step 4.
4 CMP sensor power supply voltage check :
1) With ignition switch OFF, disconnect CMP sen-
sor coupler.
2) With ignition switch ON, check voltage between 
C09-2 and C09-1 terminal. (See Fig.)
Is the voltage 10 – 14 V?Go to Step 5. Faulty “BLU/BLK” wire 
and/or “GRY/YEL” wire. 

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-91
TROUBLESHOOTING
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 Is there DTC P0403 (EGR circuit malfunction)? Go to DTC P0403 Diag. 
Flow Table.Go to Step 3.
3 Do you have SUZUKI scan tool? Go to Step 4. Go to Step 6.
4 EGR valve operation check :
1) With ignition switch OFF, install SUZUKI 
scan tool.
2) Check EGR system referring to Section 
6E2.
Is it in good condition?Go to Step 5. Go to Step 6.
5 MAP sensor check :
1) Check MAP sensor for performance refer-
ring to Section 6E2.
Is check result satisfactory?Intermittent trouble or 
faulty ECM (PCM). Check 
for intermittent referring to 
“INTERMITTENT AND 
POOR CONNECTION” in 
Section 0A.Repair or replace.
6 EGR valve power supply circuit check :
1) With ignition switch OFF, disconnect EGR 
valve coupler.
2) With ignition switch ON, check voltage 
between C04-2 and ground, C04-5 and 
ground.
Is each voltage 10 – 14 V?Go to Step 7. Faulty “BLU/BLK” wire.
7 EGR valve stepper motor coil circuit check :
1) With ignition switch OFF, connect EGR 
valve coupler and disconnect ECM (PCM) 
couplers.
2) Check resistance between C51-3-4 and 
C51-2-12, C51-2-13, C51-2-14, C51-2-15.
Is each resistance 20 – 24 Ω at 20°C (68°F)?Go to Step 8. Faulty EGR valve.
8 MAP sensor check :
1) Check MAP sensor for performance refer-
ring to Section 6E2.
Is check result satisfactory?EGR passage clogged or 
EGR valve malfunction.
If all above are OK, inter-
mittent trouble or faulty 
ECM (PCM).
Check for intermittent 
referring to “INTERMIT-
TENT AND POOR CON-
NECTION” in Section 0A.Repair or replace. 

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-93
TROUBLESHOOTING
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 EGR valve check :
1) With ignition switch OFF, disconnect connec-
tor from EGR valve.
2) Check for proper connection to EGR valve at 
each terminal.
3) If OK, check EGR valve for resistance refer-
ring to “EGR VALVE INSPECTION” in Sec-
tion 6E2.
Is check result as specified?Go to Step 3. EGR valve malfunction.
3 Wire harness check :
1) Connect connector to EGR valve.
2) Remove ECM (PCM) cover and disconnect 
connector from ECM (PCM).
3) Check for proper connection to ECM (PCM) 
at system related terminals.
4) If OK, check for resistance between the fol-
lowing terminals of ECM (PCM) connector 
disconnected.
EGR valve resistance :
C51-2-13 and C51-3-4, C51-2-14 and C51-3-4, 
C51-2-15 and C51-3-4, C51-2-12 and C51-3-4 :
20 – 24 
Ω
ΩΩ Ω at 20°C (68°F)
C51-2-13 and ground, C51-2-14 and ground, 
C51-2-15 and ground, C51-2-12 and ground :
Infinity (
∞
∞∞ ∞)
Is check result as specified?Intermittent trouble or 
faulty ECM (PCM).
Recheck referring to 
“INTERMITTENT AND 
POOR CONNECTION” in 
Section 0A.“BLU/BLK”, “LT GRN”, 
“LT GRN/WHT” “LT GRN/
YEL” or “LT GRN/RED” 
circuit open or shorted to 
ground. 

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-95
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.
3) Increase vehicle speed to 80 – 90 km/h (50 – 56 mph).
4) Keep above vehicle speed for 5 min. or more (Throttle valve opening is kept constant in this step).
5) Stop vehicle and check if pending DTC exists by using scan tool. If not, check if catalyst monitoring test has
completed by using scan tool. If not in both of above checks (i.e., no pending DTC and catalyst monitoring
test not completed), check vehicle condition (environmental) and repeat Step 3) through 5).
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 persons, 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 Exhaust system visual inspection :
1) Check exhaust system for leaks, damage 
and loose connection.
Is it in good condition?Go to Step 3. Repair or replace.
3 HO2S-2 output voltage check :
1) Check output voltage of HO2S-2 referring 
Step 2 of DTC P0136 Diag. Flow Table.
Is check result satisfactory?Replace warm up three 
way catalytic converter.Check “RED/BLK” and 
“GRY/YEL” wires for open 
and short, and connec-
tions for poor connection.
If wires and connections 
are OK, replace HO2S-2. 

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-97
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.
3) Increase vehicle speed to 80 – 90 km/h (50 – 56 mph).
4) Keep above vehicle speed for 5 min. or more (Throttle valve opening is kept constant in this step).
5) Stop vehicle and check if pending DTC exists by using scan tool. If not, check if catalyst monitoring test has
completed by using scan tool. If not in both of above checks (i.e., no pending DTC and catalyst monitoring
test not completed), check vehicle condition (environmental) and repeat Step 3) through 5).
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 persons, 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 Exhaust system visual inspection :
1) Check exhaust system for leaks, damage 
and loose connection.
Is it in good condition?Go to Step 3. Repair or replace.
3 HO2S-2 output voltage check :
1) Check output voltage of HO2S-2 referring 
Step 2 of DTC P0156 Diag. Flow Table.
Is check result satisfactory?Replace warm up three 
way catalytic converter.Check “RED/YEL” and 
“GRY/YEL” wires for open 
and short, and connec-
tions for poor connection.
If wires and connections 
are OK, replace HO2S-2. 

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-99
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.
3) Start engine and warm up it completely.
4) Increase vehicle speed to 55 km/h (35 mph) or more.
5) Keep driving above vehicle speed for 20 min or more (Change of vehicle speed is permitted in this step).
6) Release accelerator pedal, stop vehicle and run engine at speed for 2 min.
7) Check DTC and pending DTC by using scan tool.
TROUBLESHOOTING
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 Check EVAP canister purge system for opera-
tion referring to “EVAP CANISTER PURGE 
SYSTEM INSPECTION” in this section.
Is check result satisfactory?Intermittent trouble or 
faulty ECM (PCM).
Check for intermittent 
referring to “INTERMIT-
TENT AND POOR CON-
NECTION” in Section 0A.Go to Step 3.
3 Check EVAP canister purge valve for resistance 
referring to “EVAP CANISTER PURGE VALVE 
INSPECTION” in this section.
Is resistance as specified?“GRN/BLK” or “BLU/BLK” 
circuit open or short.
If wire and connections 
are OK, substitute a 
known-good ECM (PCM) 
and recheck.Replace EVAP canister 
purge valve.