6-88 ENGINE GENERAL INFORMATION AND DIAGNOSIS
DTC P0335 (DTC NO.23) CRANKSHAFT POSITION (CKP) SENSOR CIRCUIT
MALFUNCTION
WIRING DIAGRAM / CIRCUIT DESCRIPTION
REFERENCE
Connect oscilloscope between terminals C42-23 of ECM connector connected to ECM and ground and check
CKP sensor signal.
DTC CONFIRMATION PROCEDURE
1) Clear DTC and crank engine for 2 sec.
2) Select “DTC” mode on scan tool and check DTC.
ECM
5V+B
BLK/RED
YEL/BLK
C42-23
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
No CKP sensor signal for 2 seconds at engine crank-
ing.CKP sensor circuit open or short.
Crankshaft timing belt pulley teeth damaged.
CKP sensor malfunction, foreign material being
attached or improper installation.
ECM malfunction.
1. BTDC 5° (Crank angle) [B] : Waveforms at specified idle speed
[A] : Oscilloscope Waveforms [C] : Waveforms at 2000 r/min
ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-91
DTC P0340 (DTC NO.15) CAMSHAFT POSITION (CMP) SENSOR CIRCUIT MAL-
FUNCTION
WIRING DIAGRAM / CIRCUIT DESCRIPTION
REFERENCE
Connect oscilloscope between terminals E21-11 of ECM connector connected to ECM and body ground and
check CMP sensor signal. When CKP circuit is failed (open or short), ECM identify the cylinder only by CMP
sensor signal.
DTC CONFIRMATION PROCEDURE
1) Clear DTC.
2) Start engine and keep it at idle for 1 min.
3) Select “DTC” mode on scan tool and check DTC.
ECM
5V+B
BLK/RED
RED/YEL
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
C42-11
DTC DETECTING CONDITION POSSIBLE CAUSE
No CMP sensor signal during engine running (CKP
sensor signal is inputted).CMP sensor circuit open or short.
Signal rotor teeth damaged.
CMP sensor malfunction, foreign material being
attached or improper installation.
Incorrect starter signal.
ECM malfunction.
1. No.1 cylinder 3. No.3 cylinder [A] : Oscilloscope Waveforms [C] : CKP sensor signal
2. No.2 cylinder 4. No.4 cylinder [B] : Waveforms at specified idle speed [D] : CMP sensor signal
6-94 ENGINE GENERAL INFORMATION AND DIAGNOSIS
DTC P0400 EXHAUST GAS RECIRCULATION FLOW MALFUNCTION
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, 122°F or lower
2) Start engine and warm it up to normal operating temperature (70 – 110°C, 158 – 230°F) and run it at idle for
5 min.
3) Increase vehicle speed to 50 – 55 mph, 80 – 88 km/h in 5th gear or in “D” range.
4) Hold throttle valve at that opening position for 2 min. or longer.
5) Increase engine speed to 4000 r/min. in 3rd gear or in “2” range.
6) Release accelerator pedal and with engine brake applied, keep vehicle coasting (fuel cut condition) till
engine speed reaches 1500 r/min.
1. EGR valve [A] : Case of TYPE A is shown (See NOTE) [B] : Case of TYPE B is shown (See NOTE)
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
+BECM
C42-18
C42-29
C42-28 C42-17
C42-1
GRY
GRN/ORN
WHT/RED
C42-3 BRN/YEL
BLK/ORN
BLK/ORN BLK/RED1
3
1 2
4
6 5
+BECM
C41-2
C41-9
C41-17 C41-8
C42-1
GRN
GRN/ORN
WHT/RED
C42-3 BRN/YEL
BLK/ORN
BLK/ORN BLK/RED1
3
1 2
4
6 5
[A][B]
NOTE:
For TYPE A and TYPE B, refer to NOTE in “ECM VOLTAGE VALUES TABLE” for applicable model.
DTC DETECTING CONDITION POSSIBLE CAUSE
While running at specified vehicle speed after engine warm-up
During deceleration (engine speed high with closed throttle position
ON) in which fuel cut is involved, difference in intake manifold abso-
lute pressure between when EGR valve is opened at specified value
and when it is closed is larger or smaller than specified value.
✱2 driving cycle detection logic, monitoring once/1 drivingEGR valve or its circuit
EGR passage
ECM
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.
ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-97
DTC P0420 CATALYST SYSTEM EFFICIENCY BELOW THRESHOLD
WIRING DIAGRAM / CIRCUIT DESCRIPTION
ECM monitors oxygen concentration in the exhaust gas which has passed the three way catalytic converter by
HO2S-2 (2).
When the catalyst is functioning properly, the variation cycle of HO2S-2 (2) output voltage (oxygen concentra-
tion) is slower than that of HO2S-1 (1) output voltage because of the amount of oxygen in the exhaust gas which
has been stored in the catalyst (3).
REFERENCE
[A] : Oscilloscope Waveforms
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
1
2
3
ECM
WHT
ORNC42-10 C42-13
BRN
C41-13
YEL
DTC DETECTING CONDITION POSSIBLE CAUSE
While vehicle running at constant speed under other than
high load.
Time from rich or lean switching command is output till HO2S-
2 output voltage crosses 0.45 V is less than specified value.
✱2 driving cycle detection logic, monitoring once/1 drivingExhaust gas leak
Three way catalytic converter malfunction
Fuel system malfunction
HO2S-2 malfunction
HO2S-1 malfunction
6-100 ENGINE GENERAL INFORMATION AND DIAGNOSIS
DTC P0443 PURGE CONTROL VALVE CIRCUIT MALFUNCTION
WIRING DIAGRAM / CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
1) Clear DTC with ignition switch ON.
2) Select “DTC” mode on scan tool and check DTC.
INSPECTION
Fig. 1 for Step 1
1. EVAP canister purge valve [A] : Case of TYPE A is shown (See NOTE) [B] : Case of TYPE B is shown (See NOTE)
ECM
+B
BLK/RED
BLU/BLK
BLK/ORN
BLK/ORNC42-1
C42-3
1
C42-4 [A]
C42-2 [B]
NOTE:
For TYPE A and TYPE B, refer to NOTE in “ECM VOLTAGE VALUES TABLE” for applicable model.
DTC DETECTING CONDITION POSSIBLE CAUSE
Canister Purge control valve circuit is opened or
shorted.“BLU/BLK” circuit open or short
“BLK/RED” circuit open or short
Canister purge valve malfunction
Step Action Yes No
1 Check EVAP Canister Purge Valve operation.
1) With ignition switch OFF, disconnect coupler from
canister purge valve.
2) Check resistance of EVAP canister purge valve.
Resistance between
two terminals : 30 – 34 Ω at 20°C (68°F)
Resistance between
terminal and body : 1 MΩ or higher
Is it as specified?“BLU/BLK” circuit
open or short.
“BLK/RED” circuit
open or short.Replace EVAP canister
purge valve.
ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-101
DTC P0480 RADIATOR COOLING FAN CONTROL SYSTEM MALFUNCTION
WIRING DIAGRAM / CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON.
3) Warm up engine until radiator cooling fan starts to operate.
4) Check pending DTC in “ON BOARD TEST” or “PENDING DTC” mode and DTC in “DTC” mode.
INSPECTION
1. Main relay [A] : Case of TYPE A is shown (See NOTE)
2. Radiator fan relay [B] : Case of TYPE B is shown (See NOTE)
3. Radiator fan motor
BATT
80A30A
15A
BLKBLU/WHT
ECM
BLK/ORN
BLK/ORNC42-1
C42-3
L
L–
H– H
No.1
No.2
No.3
BLU
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
C41-18
GRN/RED [B]PPL/YEL [A]
BLK/RED
BLU/WHT
BLU/RED
BLK
BLU
BLU/BLK
PPL/YEL
BLU/RED
BLK/YEL
1
BRN/WHT
2
3
2
2
G02-3 [A]
C41-9 [B]
NOTE:
For TYPE A and TYPE B, refer to NOTE in “ECM VOLTAGE VALUES TABLE” for applicable model.
DTC DETECTING CONDITION POSSIBLE CAUSE
Low voltage at terminal C41-18 when engine coolant
temp. is below 97.5°C, 207.5°F.
✱2 driving cycle detection logic, continuous monitoring.“BLK/RED” or “BLU” circuit open or short
Radiator cooling fan relay malfunction
ECM malfunction
Step Action Yes No
1Was “ENGINE DIAG. FLOW TABLE” performed? Go to Step 2. Go to “ENGINE DIAG.
FLOW TABLE”.
2 Check Radiator Cooling Fan Relay and Its Circuit.
1) Turn ignition switch ON.
2) Check for voltage at terminal C41-18 of ECM
connector connected, under following condition.
See Fig. 1.
When engine coolant temp. is lower than
97.5°C, 207.5°F and A/C switch turns OFF : 10
– 14 V
Is voltage as specified?Intermittent trouble or
faulty ECM.
Check for intermittent
referring to “Intermittent
and Poor Connection” in
Section 0A.Go to Step 3.
ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-103
DTC P0500 (DTC NO.16) VEHICLE SPEED SENSOR (VSS) MALFUNCTION
WIRING DIAGRAM / CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
1) Clear DTC and warm up engine to normal operating temperature.
2) Increase vehicle speed to 50 mph, 80 km/h in 3rd gear or “2” range while observing vehicle speed displayed
on scan tool.
3) Release accelerator pedal and with engine brake applied, keep vehicle coasting (fuel cut condition) for 4
sec. or more.
4) Check pending DTC and DTC.
INSPECTION
1. VSS (vehicle speed sensor) 3. Power supply from ignition switch
2. VSS connector 4. Speedometer, P/S control module and multi information display
[A] : Case of TYPE A is shown (See NOTE) [B] : Case of TYPE B is shown (See NOTE)
ECM
5V+B
BLK/RED
BLK/ORN
PPL
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
1
4 c
a
b2
3
G02-2 [A]
C41-22[B]
NOTE:
For TYPE A and TYPE B, refer to NOTE in “ECM VOLTAGE VALUES TABLE” for applicable model.
DTC DETECTING CONDITION POSSIBLE CAUSE
VSS signal not inputted while vehicle running in “D”
range or during fuel cut at deceleration.
✱2 driving cycle detection logic, continuous monitoring“BLK/ORN” circuit open
“PPL” or “BLK/RED” circuit open or short
VSS malfunction
ECM malfunction
Speedometer 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.
Step Action Yes No
1Was “ENGINE DIAG. FLOW TABLE” per-
formed?Go to Step 2. Go to “ENGINE DIAG.
FLOW TABLE”.
2 Does speedometer indicate vehicle speed? Go to Step 3. Go to Step 5.
6-108 ENGINE GENERAL INFORMATION AND DIAGNOSIS
DTC P1450 BAROMETRIC PRESSURE SENSOR LOW/HIGH INPUT
DTC P1451 BAROMETRIC PRESSURE SENSOR PERFORMANCE PROBLEM
WIRING DIAGRAM / CIRCUIT DESCRIPTION
Barometric pressure sensor is installed in ECM.
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON.
3) Turn ignition switch ON for 2 sec., crank engine for 2 sec. and run it at idle for 1 min.
4) Check pending DTC in “ON BOARD TEST” or “PENDING DTC” mode and DTC in “DTC” mode.
INSPECTION
DTC P1450 :
Substitute a known-good ECM and recheck.
DTC P1451 :
DTC DETECTING CONDITION POSSIBLE CAUSE
DTC P1450 :
Barometric pressure : Sensor voltage is 4.7 V or higher, or
1.6 V or lowerECM (barometric pressure sensor) malfunc-
tion
DTC P1451 :
Vehicle stopped
Engine cranking
Difference between barometric pressure and intake mani-
fold absolute pressure is 26 kPa, 200 mmHg or more
Difference between intake manifold absolute pressure at
engine start and the pressure after engine start is 1.3 kPa,
10 mmHg or less.
✱2 driving cycle detection logic, monitoring once/1 driving.Manifold absolute pressure sensor and its
circuit malfunction
ECM (barometric pressure sensor) malfunc-
tion
NOTE:
Note that atmospheric pressure varies depending on weather conditions as well as altitude.
Take that into consideration when performing these check.
Step Action Yes No
1 Check Barometric Pressure Valve.
1) Connect scan tool to DLC with ignition
switch OFF.
2) Turn ignition switch ON and select “DATA
LIST” mode on scan tool.
3) Check manifold absolute pressure. See Fig.
1.
Is it barometric pressure (approx. 100 kPa, 760
mmHg) at sea level?Substitute a known-good
ECM and recheck.Go to Step 2.