6-34 ENGINE GENERAL INFORMATION AND DIAGNOSIS
IGNITION ADVANCE (IGNITION TIMING ADVANCE FOR NO.1 CYLINDER, °)
Ignition timing of NO.1 cylinder is commanded by ECM. The actual ignition timing should be checked by using
the timing light.
INTAKE AIR TEMP. (°C, °F)
It is detected by intake air temp. sensor and used to determine the amount of air passing into the intake manifold
as air density varies with temperature.
MAF (MASS AIR FLOW RATE, gm/s, lb/min)
It represents total mass of air entering intake manifold which is computed based on signals from MAP sensor,
IAT sensor, TP sensor, etc.
THROTTLE POS (ABSOLUTE THROTTLE POSITION, %)
When throttle position sensor is fully closed position, throttle opening is indicated as 0% and 100% full open
position.
OXYGEN SENSOR B1 S1 (HEATED OXYGEN SENSOR-1, V)
It indicates output voltage of HO2S-1 installed on exhaust manifold (pre-catalyst).
OXYGEN SENSOR B1 S2 (HEATED OXYGEN SENSOR-2, V)
It indicates output voltage of HO2S-2 installed on exhaust pipe (post-catalyst). It is used to detect catalyst dete-
rioration.
DESIRED IDLE (DESIRED IDLE SPEED, rpm)
The Desired Idle Speed is an ECM internal parameter which indicates the ECM requested idle. If the engine is
not running, this number is not valid.
TP SENSOR VOLT (THROTTLE POSITION SENSOR OUTPUT VOLTAGE, V)
The Throttle Position Sensor reading provides throttle valve opening information in the form of voltage.
INJ PULSE WIDTH (FUEL INJECTION PULSE WIDTH, msec.)
This parameter indicates time of the injector drive (valve opening) pulse which is output from ECM (but injector
drive time of NO.1 cylinder for multiport fuel injection).
IAC FLOW DUTY (IDLE AIR (SPEED) CONTROL DUTY, %)
This parameter indicates current flow time rate within a certain set cycle of IAC valve (valve opening rate) which
controls the amount of bypass air (idle speed).
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.
BATTERY VOLTAGE (V)
This parameter indicates battery positive voltage inputted from main relay to ECM.
CANIST PURGE DUTY (EVAP CANISTER PURGE FLOW DUTY, %)
This parameter indicates valve ON (valve open) time rate within a certain set cycle of EVAP purge solenoid
valve which controls the amount of EVAP purge.
0% means that the purge valve is completely closed while 100% is a fully open valve.
CLOSED THROTTLE POSITION (ON/OFF)
This parameter will read ON when throttle valve is fully closed, or OFF when the throttle is not fully closed.
FUEL CUT (ON/OFF)
ON : Fuel being cut (output signal to injector is stopped)
OFF : Fuel not being cut
ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-43
Resistance Check
1) Disconnect ECM couplers from ECM with ignition switch
OFF.
2) Check resistance between each terminal of connectors dis-
connected.
TERMINAL RESISTANCE TABLE
For TYPE A (Refer to NOTE in “ECM VOLTAGE VALUES TABLE” for applicable model) CAUTION:
Never touch terminals of ECM itself or connect voltmeter
or ohmmeter.
CAUTION:
Be sure to connect ohmmeter probe from wire harness
side of coupler.
Be sure to turn OFF ignition switch for this check.
Resistance in table below represents that when parts
temperature is 20°C (68°F).
1. ECM coupler disconnected
2. Ohmmeter
TERMINALS CIRCUIT STANDARD
RESISTANCE
C42-7 to G02-6 HO2S-1 heater (if equipped) 5.0 – 6.4 Ω
C41-4 to G02-6 HO2S-2 heater (if equipped) 12.0 – 14.3 Ω
C42-9 to C41-5/6 No.1 injector 11.3 – 13.8 Ω
C42-21 to C41-5/6 No.2 injector 11.3 – 13.8 Ω
C42-31 to C41-5/6 No.3 injector 11.3 – 13.8 Ω
C42-8 to C41-5/6 No.4 injector 11.3 – 13.8 Ω
C41-2 to C41-5/6 EGR valve (stepper motor coil 1) (if equipped) 20 – 24 Ω
C41-9 to C41-5/6 EGR valve (stepper motor coil 2) (if equipped) 20 – 24 Ω
C41-8 to C41-5/6 EGR valve (stepper motor coil 3) (if equipped) 20 – 24 Ω
C41-17 to C41-5/6 EGR valve (stepper motor coil 4) (if equipped) 20 – 24 Ω
C42-4 to C41-5/6 EVAP canister purge valve 30 – 34 Ω
C41-19 to G02-6 Fuel pump relay 56 – 146 Ω
C41-1 to Body ground A/C compressor clutch 3 – 5.5 Ω
C41-18 to C41-5/6 Radiator fan control relay No.1 56 – 146 Ω
C41-10 to G02-17 Main relay 56 – 146 Ω
C42-1 to Body ground Ground Continuity
C42-2 to Body ground Ground Continuity
C42-3 to Body ground Ground Continuity
ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-55
DTC P0110 (DTC NO.18) INTAKE AIR TEMP. (IAT) CIRCUIT MALFUNCTION
WIRING DIAGRAM / CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
1) Clear DTC, start engine and keep it at idle for 1 min.
2) Select “DTC” mode no scan tool and check DTC.
INSPECTION
C42-10
C42-15
5V
ECM
LT GRN/BLK
ORN
C42 (31P) C41 (24P) G02 (17P)1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18 19 20 21
22 23 24 25 26 28 27 29 30 315 6
1 2 3 4 5 6 7
11 12
9 10 11 13 12 14 15 16
16 171 2
7 8
13 14 3 4
9 10
15 17 188
19 20 21 22 23 24
DTC DETECTING CONDITION POSSIBLE CAUSE
Low intake air temperature (High voltage-High resistance)
or
High intake air temperature (Low voltage-Low resistance)“LT GRN/BLK” circuit open or shorted to
power.
“ORN” circuit open
IAT sensor malfunction
ECM malfunction
NOTE:
When DTC P0105 (No.11), P0110 (No.18), P0115 (No.19) and P0120 (No.13) are indicated together, it
is possible that “ORN” circuit is open.
Before inspecting, be sure to check that ambient temperature is higher than – 40°C (– 40°F).
Step Action Yes No
1Was “ENGINE DIAG. FLOW TABLE” per-
formed?Go to Step 2. Go to “ENGINE DIAG.
FLOW TABLE”.
2 Check IAT Sensor and Its Circuit.
1) Connect scan tool to DLC with ignition
switch OFF.
2) Turn ignition switch ON.
3) Check intake air temp. displayed on scan
tool. See Fig. 1.
Is – 40°C (– 40°F) or 119°C (246°F) indicated?Go to Step 3. Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection” in
Section 0A.
ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-57
Fig. 3 for Step 4
DTC P0115 (DTC NO.19) ENGINE COOLANT TEMPERATURE (ECT) CIRCUIT
MALFUNCTION
WIRING DIAGRAM / CIRCUIT DESCRIPTION
C42-14
5V
ECM
LT GRN
ORN
YEL/GRN
C42-10
C42 (31P) C41 (24P) G02 (17P)1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18 19 20 21
22 23 24 25 26 28 27 29 30 315 6
1 2 3 4 5 6 7
11 12
9 10 11 13 12 14 15 16
16 171 2
7 8
13 14 3 4
9 10
15 17 188
19 20 21 22 23 24
DTC DETECTING CONDITION POSSIBLE CAUSE
Low engine coolant temperature (High voltage-High resis-
tance)
or
High engine coolant temperature (Low voltage-Low resis-
tance)“LT GRN” circuit open or shorted to power
“ORN” circuit open
ECT sensor malfunction
ECM malfunction
NOTE:
Before inspecting, be sure to check that coolant temp. meter in combination meter indicates normal
operating temperature (Engine is not overheating).
When this DTC and P1709 are stored together, also clear DTC stored in TCM after completion of
repair.
When DTC P0105 (No.11), P0110 (No.18), P0115 (No.19) and P0120 (No.13) are indicated together, it
is possible that “ORN” circuit open.
ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-63
DTC P0121 THROTTLE POSITION CIRCUIT RANGE/PERFORMANCE PROB-
LEM
WIRING DIAGRAM / CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF. Clear DTC with ignition switch ON, check vehicle and environmental condition for :
–Altitude (barometric pressure) : 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)
–Ambient temp. : –10°C, 14°F or higher
–Intake air temp. : 70°C, 158°F or lower
–Engine coolant temp. : 70 – 110°C, 158 – 230°F
2) Warm up engine to normal operating temperature.
3) Increase vehicle speed to 30 – 40 mph, 50 – 60 km/h in 3rd gear or “D” range and hold throttle valve at that
opening position for 1 min.
4) Stop vehicle.
5) Check DTC in “DTC” mode and pending DTC in “ON BOARD TEST” or “PENDING DTC” mode.
[A] : Case of TYPE A is shown (See NOTE) [B] : Case of TYPE B is shown (See NOTE)
C42-10
C42-22
5V5V
ECM
GRY/RED
GRY/BLU
ORN
C42 (31P) C41 (24P) G02 (17P)1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18 19 20 21
22 23 24 25 26 28 27 29 30 315 6
1 2 3 4 5 6 7
11 12
9 10 11 13 12 14 15 16
16 171 2
7 8
13 14 3 4
9 10
15 17 188
19 20 21 22 23 24
C42-16 [B]C41-3 [A]
NOTE:
For TYPE A and TYPE B, refer to NOTE in “ECM VOLTAGE VALUES TABLE” for applicable model.
DTC DETECTING CONDITION POSSIBLE CAUSE
DTC will set when the following conditions are detected.
After engine warmed up.
While vehicle running at specified engine speed.
No change in intake manifold pressure (constant throttle opening)
Difference between actual throttle opening (detected from TP sensor)
and opening calculated by ECM (Obtained on the basis of engine
speed and intake manifold pressure) in larger than specified value.
✱2 driving cycle detection logic, continuous monitoringTP sensor malfunction
High resistance in the circuit
ECM malfunction
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.
6-66 ENGINE GENERAL INFORMATION AND DIAGNOSIS
DTC P0130 (DTC NO.14) HEATED OXYGEN SENSOR (HO2S) CIRCUIT MAL-
FUNCTION (SENSOR-1)
WIRING DIAGRAM / CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF. Clear DTC with ignition switch ON, check vehicle and environmental condition for :
–Altitude (barometric pressure) : 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)
–Ambient temp. : –10°C, 14°F or higher
–Intake air temp. : 70°C, 158°F or lower
2) Warm up engine to normal operating temperature.
3) Drive vehicle at 30 – 40 mph, 50 – 60 km/h for 2 min.
4) Stop vehicle and run engine at idle for 2 min.
5) Check DTC in “DTC” mode and pending DTC in “ON BOARD TEST” or “PENDING DTC” mode.
ECM
WHT
ORNC42-10 C42-13
E11
C42 (31P) C41 (24P) G02 (17P)1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18 19 20 21
22 23 24 25 26 28 27 29 30 315 6
1 2 3 4 5 6 7
11 12
9 10 11 13 12 14 15 16
16 171 2
7 8
13 14 3 4
9 10
15 17 188
19 20 21 22 23 24
DTC DETECTING CONDITION POSSIBLE CAUSE
When running at idle speed after engine warmed up and
running at specified vehicle speed, HO2S-1 output volt-
age does not go below 0.3 V or over 0.6 V.
✱2 driving cycle detection logic, Monitoring once/1 driving.Heated oxygen sensor-1 malfunction
“WHT” or “ORN” circuit open (poor connection)
or short
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.
6-72 ENGINE GENERAL INFORMATION AND DIAGNOSIS
DTC P0136 HEATED OXYGEN SENSOR (HO2S) CIRCUIT MALFUNCTION
(SENSOR-2)
WIRING DIAGRAM / CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
Clear DTC with ignition switch ON, check vehicle and environmental condition for :
–Altitude (barometric pressure) : 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)
–Ambient temp. : –10°C, 14°F or higher
–Intake air temp. : 70°C, 158°F or lower
–No exhaust gas leakage and loose connection
2) Warm up engine to normal operating temperature.
3) Drive vehicle under usual driving condition for 5 min. and check HO2S-2 output voltage and “short term fuel
trim” with “Data List” mode on scan tool, and write it down.
4) Stop vehicle (don’t turn ignition switch OFF).
5) Increase vehicle speed to higher than 20 mph, 32 km/h and then stop vehicle.
ECM
E11BRN
ORNC42-10 C41-13
C42 (31P) C41 (24P) G02 (17P)1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18 19 20 21
22 23 24 25 26 28 27 29 30 315 6
1 2 3 4 5 6 7
11 12
9 10 11 13 12 14 15 16
16 171 2
7 8
13 14 3 4
9 10
15 17 188
19 20 21 22 23 24
YEL
DTC DETECTING CONDITION POSSIBLE CAUSE
DTC will set when one of the following conditions is detected.
Max. output voltage of HO2S-2 is lower than specified value or
Min. output voltage is higher than specified value while vehicle
driving.
Engine is warmed up and HO2S-2 voltage is 4.5 V or more.
(circuit open)
✱2 driving cycle detection logic, monitoring once/1 driving.Exhaust gas leakage
“BRN”, “YEL” or “ORN” circuit open or
short
Heated oxygen sensor-2 malfunction
Fuel system malfunction
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.
6-74 ENGINE GENERAL INFORMATION AND DIAGNOSIS
DTC P0141 HEATED OXYGEN SENSOR (HO2S) HEATER CIRCUIT MALFUNC-
TION (SENSOR-2)
WIRING DIAGRAM / CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF once and then ON.
2) Clear DTC, start engine and warm up engine to normal operating temperature.
3) Keep it at 2000 r/min for 2 min.
4) Check pending DTC in “ON BOARD TEST” or “PENDING DTC” mode and DTC in “DTC” mode.
ECM
BLK/WHT
PNK/BLU
C41-4 IG1
C42 (31P) C41 (24P) G02 (17P)1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18 19 20 21
22 23 24 25 26 28 27 29 30 315 6
1 2 3 4 5 6 7
11 12
9 10 11 13 12 14 15 16
16 171 2
7 8
13 14 3 4
9 10
15 17 188
19 20 21 22 23 24
DTC DETECTING CONDITION POSSIBLE CAUSE
DTC will set when any one of the following conditions is
met.
Low voltage at terminal C41-4 for specified time after
engine start or while engine running at high load.
High voltage at terminal C41-4 while engine running
under other than above condition.
✱2 driving cycle detection logic, continuous monitoring.HO2S-2 heater circuit open or shorted to ground
ECM malfunction