2001 SUZUKI GRAND VITARA start circuit

6-1-82 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
DTC P0325 (DTC No.43) Knock Sensor Circuit Malfunction
CIRCUIT DESCRIPTION
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) Start engine and run it for 10 sec.
4) Check DTC by using scan tool.
1. Knock sensor
2. ECM (PCM)
DTC DETECTING CONDITION TROUBLE AREA
DTC will set when one of the following condition is
detected.
• KNOCK sensor voltage is 0.90 V or less, or
• KNOCK sensor voltage is 3.98 V or more• “WHT” circuit open or shorted to ground
• KNOCK sensor malfunction
• ECM malfunction

6-1-84 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
DTC P0335 Crankshaft Position Sensor Circuit Malfunction
WIRING DIAGRAM
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 and run
engine at idle speed for 10 sec.
3) Check DTC by using scan tool.
1. CKP sensor
2. ECM (PCM)
DTC DETECTING CONDITION TROUBLE AREA
CKP sensor signal is not input while 100 pulses of
CMP sensor signal are input after engine start.CKP sensor circuit
CKP sensor
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)

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.

6-1-92 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
DTC P0403 (DTC No.51) Exhaust Gas Recirculation Circuit Malfunction
WIRING DIAGRAM
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) Start engine and run it for 10 sec.
4) Check DTC by using scan tool.
1. Main fuse 4. ECM (PCM)
2. Main relay
3. EGR valve
DTC DETECTING CONDITION TROUBLE AREA
High voltage is detected at EGR valve stepping motor
electrical circuit for specified time continuously.
(Circuit open or short).EGR valve (stepping motor) or its 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)

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.

6-1-114 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
DTC P1500 Engine Starter Signal Circuit Malfunction
WIRING DIAGRAM
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 by using scan tool, then start engine and run it for 3 min. or more.
3) Check pending DTC by using scan tool.
TROUBLESHOOTING
1. Engine start switch in ignition (main) switch 2. Starting motor 3. Transmission range sensor (switch) 4. ECM (PCM)
DTC DETECTING CONDITION TROUBLE AREA
•Engine starts even though vehicle is at stop and engine start signal is
not inputted.
or
•Engine start signal is inputted continuously for specified time while
engine is running.
(2 driving cycle detection logic)•Engine start 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)
Step Action Yes No
1Was “ENGINE DIAG. FLOW TABLE” per-
formed?Go to Step 2. Go to “ENGINE DIAG. FLOW TABLE”
in this section.
2 Check for voltage at terminal C51-1-24 of
ECM (PCM) connector connected, under fol-
lowing condition.
Engine starter signal specification :
While engine cranking : 6 – 14 V
After starting engine : 0 – 1 V
Is voltage as specified?Poor C51-1-24 connection or
intermittent trouble.
Check for intermittent referring to
“INTERMITTENT AND POOR
CONNECTION” in Section 0A.
If wire and connections are OK,
substitute a known-good ECM
(PCM) and recheck.“BLK/YEL” circuit open.

6-1-120 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
3 1) Start engine and warm it up to normal oper-
ating temperature.
2) Keep it running at specified idle speed.
Is fuel pressure then within 210 – 260 kPa
(2.1 – 2.6 kg/cm
2, 29.8 – 37.0 psi)?Normal fuel pressure. Clogged vacuum passage
for fuel pressure regula-
tor or faulty fuel pressure
regulator.
4 Is there fuel leakage from fuel feed line hose,
pipe or joint?Fuel leakage from hose,
pipe or joint.Go to Step 10.
5 Was fuel pressure higher than spec. in Step 1? Go to Step 6. Go to Step 7.
6 1) Disconnect fuel return hose from fuel pipe
and connect new hose to it.
2) Put the other end of new return hose into
approved gasoline container.
3) Operate fuel pump.
Is specified fuel pressure obtained then?Restricted fuel return
hose or pipe.Faulty fuel pressure regu-
lator.
7 Was no fuel pressure applied in Step 1? Go to Step 8. Go to Step 9.
(Low pressure is mea-
sured.)
8 With fuel pump operated and fuel return hose
blocked by pinching it, is fuel pressure applied?Faulty fuel pressure regu-
lator.Shortage of fuel or fuel
pump or its circuit defec-
tive (Refer to “TABLE B-
1”).
9 1) Operate fuel pump.
2) With fuel return hose blocked by pinching it,
check fuel pressure.
Is it 450 kPa (4.5 kg/cm
2, 64.0 psi) or more?Faulty fuel pressure regu-
lator.Clogged fuel filter,
restricted fuel feed hose
or pipe, faulty fuel pump
or fuel leakage from hose
connection in fuel tank.
10 1) Disconnect fuel return hose from fuel pipe
and connect new hose to it.
2) Put the other end of new return hose into
approved gasoline container.
3) Check again if specified fuel pressure is
retained.
While doing so, does fuel come out return
hose?Faulty fuel pressure regu-
lator.Fuel leakage from injec-
tor, faulty fuel pump
(faulty check valve in fuel
pump) or fuel leakage
from fuel pressure regula-
tor diaphragm. Step Action Yes No

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-123
Table B-5 A/C Signal Circuits Inspection (If Equipped)
WIRING DIAGRAM
INSPECTION
1. A/C control module (amplifier)
2. ECM (PCM)
Step Action Yes No
1 Check A/C Signal Circuit.
1) Check voltage at terminal E61-17 with ignition
switch ON.
A/C signal circuit specification :
A/C switch and/or heater blower switch OFF (A/
C is not operating) : 10 – 14 V
Both A/C switch and heater blower switch ON :
0 – 1.5 V
Are check result as specified?Go to Step 2.“YEL/BLK” circuit open or
short, Evaporative tem-
perature is below 1°C
(34°F) or faulty A/C sys-
tem.
2 Check A/C Cut Signal Circuit.
1) Check voltage at terminal E61-8.
A/C cut signal specification :
While engine running and A/C switch and/or
heater blower switch OFF
(A/C is not operating) : 0 – 1.5 V
While engine running at idle speed and both A/
C switch and heater blower switch ON
(A/C is operating) : 10 – 14 V
Are check result as specified?A/C control signal cir-
cuits are in good con-
dition.“GRY/WHT” circuit open
or short, Poor perfor-
mance of ECT sensor, TP
sensor, Engine start sig-
nal inputted or A/C ampli-
fier malfunction.
If none of the above
exists, substitute a
known-good ECM (PCM)
and recheck.