
ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-21
For A/T system (Refer to Section 7B1 for diagnosis)
P0505Idle air control system mal-
functionDifference between desired idle speed 
and actual idle speed continues to 
exceed specified value for longer than 
specified time.2 driving 
cyclesNot
applicable
P0601 
(No.71)Internal control module mem-
ory check sum errorData write error (or check sum error) 
when written into ECM1 driving 
cycle1 driving 
cycle
P1408Manifold absolute pressure 
sensor circuit malfunctionManifold absolute pressure sensor 
output voltage is higher or lower than 
specified value (or sensor circuit 
shorted to ground or open).2 driving 
cyclesNot
applicable
P1450Barometric pressure sensor 
circuit malfunctionBarometric pressure is lower or higher 
than specification.1 driving 
cycleNot
applicable
P1451Barometric pressure sensor 
performance problemDifference between intake manifold 
pressure and barometric pressure is 
larger than specification.2 driving 
cyclesNot
applicable
P1500Engine starter signal circuit 
malfunctionEngine starts with no starter signal or 
signal input during long period after 
start.2 driving 
cyclesNot
applicable
P1510ECM back-up power supply 
malfunctionNo back-up power after starting 
engine.1 driving 
cycleNot
applicable DTC NO. DETECTED ITEMDETECTING CONDITION
(DTC will set when detecting : )MIL
(vehicle
without 
monitor 
connector)MIL
(vehicle 
with 
monitor
connector)
DTC NO. DETECTED ITEMDETECTING CONDITION
(DTC will set when detecting : )MIL
(vehicle
without 
monitor 
connector)MIL
(vehicle 
with 
monitor
connector)
P0705 
(No.72)Transmission range switch cir-
cuit malfunctionMultiple signals inputted simulta-
neously or P, R, N, D, 2 or L range sig-
nal not inputted while running at 
60km/h or more.2 driving 
cyclesNot
applicable
P0715 
(No.76)Input speed sensor circuit 
malfunctionInput speed sensor signal is lower 
than specification while running.2 driving 
cyclesNot
applicable
P0720 
(No.75)Output speed sensor circuit 
malfunctionOutput speed sensor signal not input-
ted while VSS signal being inputted.2 driving 
cyclesNot
applicable
P0741TCC (lock-up) solenoid perfor-
mance or stuck offActual TCC operation does not agree 
with ON/OFF control from PCM to 
TCC.2 driving 
cyclesNot
applicable
P0743 
(No.65) 
(No.66)TCC (lock-up) solenoid electri-
calMonitor signal OFF is detected when 
TCC control solenoid is ON or monitor 
signal ON is detected when it is OFF.1 driving 
cycleNot
applicable
P0751Shift solenoid A (#1) perfor-
mance or stuck offGear change control from PCM to A/T 
does not agree with actual gear posi-
tion of A/T.2 driving 
cyclesNot
applicable 

6-1-28 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
TP SENSOR VOLT (TP Sensor Output Voltage, V)
Throttle Position Sensor reading provides throttle valve opening information in the from of voltage.
O2S B1 S1 (HO2S Bank 1 Sensor 1 Output Voltage, V) / O2S B2 S1 (HO2S Bank 2 Sensor 1 Output 
Voltage, V)
It indicates output voltage of HO2S SENSOR 1 installed on exhaust manifold (pre-catalyst).
O2S B1 S2 (HO2S Bank 1 Sensor 2 Output Voltage, V) / O2S B2 S2 (HO2S Bank 2 Sensor 2 Output 
Voltage, V)
If indicates output voltage of HO2S SENSOR 2 installed on exhaust pipe (post-catalyst). It is used to detect cat-
alyst deterioration.
FUEL SYSTEM B1 (Fuel System Bank 1 Status) / Fuel System B2 (Fuel System Bank 2 Status)
Air/fuel ratio feedback loop status displayed as one of the followings.
OPEN : Open loop-has not yet satisfied conditions to go closed loop.
CLOSED : Closed loop-using oxygen sensor(s) as feedback for fuel control.
OPEN-DRIVE COND : Open loop due to driving conditions (Power enrichment, etc.).
OPEN SYS FAULT : Open loop due to detected system fault.
CLOSED-ONE O2S : Closed loop, but fault with at least one oxygen sensor may be using single oxygen sensor
for fuel control.
CALC LOAD (Calculated Load Value, %)
Engine load displayed as a percentage of maximum possible load. Value is calculated mathematically using the
formula : actual (current) intake air volume ÷ maximum possible intake air volume x 100%.
TOTAL FUEL TRIM (%)
The value of total fuel trim is obtained by putting values of short term fuel trim and long term fuel trim together.
This value indicates how much correction is necessary to keep the air/fuel mixture stoichiometrical.
CANIST PRG DUTY (EVAP Canister Purge Flow Duty, %)
This parameter indicates valve ON (valve open) time rate within a certain set cycle of EVAP canister purge valve
which controls the amount of EVAP purge.
VEHICLE SPEED (km/h, MPH)
It is computed based on pulse signals from vehicle speed sensor on transfer or transmission.
FUEL CUT (ON/OFF)
ON : Fuel being cut (output signal to injector is stopped).
OFF : Fuel not being cut.
MAP (Manifold Absolute Pressure, mmHg, kPa)
This parameter indicates the pressure in the intake manifold absolute pressure.
A/C CONDENSER FAN (ON/OFF)
This parameter indicates the state of the A/C Condenser Fan control signal.
BLOWER FAN (ON/OFF)
This parameter indicates the state of the blower fan motor switch. 

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-29
EGR VALVE (%)
This parameter indicates opening rate of EGR valve which controls the amount of EGR flow.
A/C SWITCH (ON/OFF)
ON : Command for operation being output from A/C amplifier to compressor.
OFF : Command for operation not being output.
PSP SWITCH (ON/OFF)
ON : PSP switch detects P/S operation. (high P/S pressure)
OFF : PSP switch not detects P/S operation.
PNP SIGNAL (Transmission Range Switch, P/N or D range)
Whether the transmission range switch (P/N position switch) at P or N range or at R, D, 2 or L range is displayed.
If at P or N range, “P/N range” is displayed and if at R, D, 2 or L range, “D range” is displayed.
FUEL TANK LEVEL (%)
This parameter indicates approximate fuel level in the fuel tank. As the detectable range of the fuel level sensor
is set as 0 to 100 %, however, with some models whose fuel tank capacity is smaller, the indicated fuel level may
be only 70 % even when the fuel tank is full.
ELECTRIC LOAD (ON/OFF)
ON : Small light switch ON or rear window defogger switch ON.
OFF : Small light switch OFF and rear window defogger switch OFF.
VSS (4-A/T) (km/h, MPH)
It is computed by using pulse signals from vehicle speed sensor on 4-speed automatic transmission.
THROT POS LEVEL (Throttle Position Level For 4-A/T, “0”, “1”, “2”, “3”, “4”,“5”,“6” or “7”)
This parameter indicates which level (zone) the throttle valve opening is in.
The throttle opening is divided into 8 levels (zones) from “0” (about idle position) to “7” (about full open) and sig-
nals are assigned to each opening level (zone). PCM controls the automatic gear change of the automatic trans-
mission by using these signals according to the signal from the TP sensor.
GEAR POSITION (1ST, 2ND, 3RD or 4TH)
The gear position is determined on the basis of the command state signals generated from PCM to shift sole-
noids A and B (#1 and #2) and displayed as shown in the table below.
SHIFT SOL #1 CON/MON (Shift Solenoid #1, A Command/monitor, ON/OFF)
CON-ON : ON command being output to shift solenoid #1, A.
CON-OFF : ON command not being output.
MON-ON : Electricity being passed to shift solenoid #1, A.
MON-OFF : Electricity not being passed.SHIFT SOLENOID-A SHIFT SOLENOID-B
DISPLAY1ST ON OFF
2ND ON ON
3RD OFF ON
4TH OFF OFF 

6-1-30 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
SHIFT SOL #2 CON/MON (Shift Solenoid #2, B Command/monitor, ON/OFF)
CON-ON : ON command being output to shift solenoid #2, B.
CON-OFF : ON command not being output.
MON-ON : Electricity being passed to shift solenoid #2, B.
MON-OFF : Electricity not being passed.
TCC SOL CON/MON (Torque Converter Clutch Solenoid Command/monitor, ON/OFF)
CON-ON : ON command being output to TCC solenoid.
CON-OFF : ON command not being output.
MON-ON : Electricity being passed to TCC solenoid.
MON-OFF : Electricity not being passed.
TRANS RANGE (Transmission Range, P, R, N, D, 2 or L)
It indicates transmission range according to transmission range switch signal.
BRAKE SW (Brake, Stop Lamp, Switch, ON/OFF)
OFF : Brake pedal is released.
ON : Brake pedal is depressed.
O/D OFF SW (Overdrive Cut Switch, ON/OFF)
OFF : Overdrive cut switch OFF.
ON : Overdrive cut switch ON.
MODE SELECT SW (Power/normal Change Switch, Power/normal)
POWER : Switch button is at POWER position.
NORMAL : Switch button is at NORMAL position.
4WD-L SW (4WD-LOW Switch, ON/OFF)
ON : Transfer lever is shifted to 4L position.
OFF : Transfer lever is shifted to 4H or 2H position. 

ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE) 6-1-39
C51-3-9 Throttle position sensor0.5 – 1.2 VIgnition switch ON, Throttle valve at 
idle position
3.4 – 4.7 VIgnition switch ON, Throttle valve at 
full open position
C51-3-10 Mass air flow sensor1.0 – 1.6 V Ignition switch ON and engine stops
1.7 – 2.0 V With engine running at idle speed
C51-3-11Heated oxygen sensor-1 (bank 1)
(if equipped)Deflects between
 over and under 0.45 VWhile engine running at 2,000 r/min. 
for 1 min. or longer after warmed up
C51-3-12 Ground for TP sensor – –
C51-3-13 Power source for TP sensor
4.75 – 5.25 V Ignition switch ON
C51-3-14 Power source for MAP sensor
C51-3-15 Power source 10 – 14 V Ignition switch ON
C51-3-16 – – –
C51-3-17 Ground – –
C51-3-18Pressure switch in 4WD air pump 
assembly10 – 14 VIgnition switch ON, Transfer lever : 
4H or 4L range 
0 – 1 VIgnition switch ON, Transfer lever : 
2H range 
C51-3-19 – – –
C51-3-20 Ignition switch 10 – 14 V Ignition switch ON
C51-3-21Heated oxygen sensor-1 (bank 2)
(if equipped)Deflects between over 
and under 0.45 VWhile engine running at 2,000 r/min. 
for 1 min. or longer after warmed up
C51-3-22Heated oxygen sensor-2 (bank 1)
(if equipped)Deflects between over 
and under 0.45 VWhile engine running at 2,000 r/min. 
for 1 min. or longer after warmed up
C51-3-23Heated oxygen sensor-2 (bank 2)
(if equipped)Deflects between over 
and under 0.45 VWhile engine running at 2,000 r/min. 
for 1 min. or longer after warmed up
C51-3-24 Ground for ECT sensor – –
C51-3-25 Ground for IAT sensor, MAP sensor – –
C51-3-26 Ground for CMP sensor – –
C51-1-1 Shift solenoid B (A/T vehicle) 0 – 1 V Ignition switch ON
C51-1-2 Shift solenoid A (A/T vehicle) 10 – 14 V Ignition switch ON
C51-1-3 – – –
C51-1-4 IAC valve (stepper motor coil 2) – –
C51-1-5 IAC valve (stepper motor coil 1) – –
C51-1-6Transmission range switch “R”
(A/T vehicle)10 – 14 VIgnition switch ON, selector lever :
“R” range
0 – 1 VIgnition switch ON, selector lever : 
Other than “R”
C51-1-7Transmission range switch “P”
(A/T vehicle)10 – 14 VIgnition switch ON, selector lever : 
“P” range
0 – 1 VIgnition switch ON, selector lever : 
Other than “P” range
C51-1-8 TCC solenoid (A/T vehicle) 0 – 1 V Ignition switch ON
C51-1-9 4WD air pump assembly10 – 14 VIgnition switch ON, Transfer lever : 
4H or 4L range 
0 – 1 VIgnition switch ON, Transfer lever : 
2H range  TERMINAL CIRCUIT NORMAL VOLTAGE CONDITION 

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 

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. 

6-1-122 ENGINE GENERAL INFORMATION AND DIAGNOSIS (H27 ENGINE)
3 Check IAC valve referring to “IAC VALVE 
INSPECTION” in Section 6E2.
Is check result as specified?Go to Step 4. IAC valve malfunction, “BLU/
BLK”, “LT GRN/BLK”, “PPL/
BLK”, “GRY/BLU” or “PPL/
YEL” wire open or short or 
poor coupler connection.
If all above are OK, substi-
tute a known-good ECM 
(PCM) and recheck.
4 Was idle speed within specification in 
Step 1?Check for following : 
FIA valve, Vacuum leaks, air inhal-
ing, EVAP canister purge control 
system, accessory engine load, 
stuck of PCV valve, clog of idle air 
passage, MAF sensor, TP sensor, 
ECT sensor, EGR valve malfunc-
tion (leakage from valve seat), A/C 
signal, transmission range switch 
signal and power steering switch 
signal.Go to Step 5.
5 Was idle speed higher than specification 
in Step 1?Go to Step 6. Go to Step 8.
6 Check A/C (input) signal circuit referring 
to Step 1 of “Table B-5”. (A/C signal can 
be also checked by using SUZUKI scan 
tool.)
Is it in good condition?Go to Step 7. A/C signal circuit open or 
short, or A/C system mal-
function.
7 Was IAC duty less than about 2% in Step 
1 of this table?
Check FIA valve.
Check abnormal air inhaling from 
intake manifold, throttle body, PCV 
valve and EVAP canister purge 
control system.Check TP sensor (closed 
throttle position) and ECT 
sensor for performance.
If sensors are OK, substitute 
a known-good ECM (PCM) 
and recheck.
8 Check transmission range switch signal 
referring to “INSPECTION OF ECM 
(PCM) AND ITS CIRCUIT” in this section.
Is check result satisfactory?Go to Step 9. Transmission range switch 
malfunction or its circuits 
open or short.
9 Was IAC duty more than about 30% in 
Step 1 of this table?Check parts or system which can 
cause engine low idle.
Check FIA valve.
Air inhaling from between throttle 
body and MAF sensor, EGR valve 
malfunction (leakage from valve 
seat), accessory engine load, clog 
of idle air passage and etc.Substitute a known-good 
ECM (PCM) and recheck. Step Action Yes No