Engine Controls - Tests W/codes - 4-CYL: Diagnosis

SELF-DIAGNOSTICS

Note. Code diagnostic hints table may be used to determine a common cause for a code to be set.

Codes	Diagnostic Hints
11	Momentary Interruption Of Power Supply To ECU
12	No "G" or "NE" (RPM) Ignition Signal To ECU Within 2 Seconds After Engine Is Cranked
13	No "NE" (RPM) Ignition Signal To ECU When Engine Speed Is Greater Than Approximately 1000 RPM
14	No IGF Ignition Signal To ECU From Ignitor Several Times In Succession
16	Fault In Transmission/Transaxle ECU
21	Defective O2 Sensor, Open Or Short Circuit In O2 Sensor Signal
22	Open Or Short Circuit In Coolant Temp. Sensor Signal
24	Open Or Short Circuit In Intake Air Temp. Sensor Signal
25	Lean Signal Sent By O2 Sensor For Several Seconds
26	Rich Signal Sent By O2 Sensor For Several Seconds
27	Open Or Short Circuit In Sub-O2 Sensor Signal
28	Defective No. 2 O2 Sensor Open Or Short Circuit In No. 2 O2 Sensor Signal
31	Open Or Short Circuit In Airflow Meter Or Vacuum Sensor Signal
32	Open Or Short Circuit Between Airflow Meter Terminals
34	Turbocharger Pressure Is Abnormal
35	Open Or Short Circuit In Turbocharger Pressure Sensor Or High Altitude Compensator Signal
41	Open Or Short Circuit In Throttle Position Sensor Signal
42	No SPD Signal From Vehicle Speed Sensor For Several Seconds With Engine Speed Approximately 2500-5500 RPM
43	No STA Signal To ECU Until Engine Reaches 800 RPM With Vehicle Not Moving
51	(1) Problem In One Of 3 Circuits Monitored By ECU
52	Open Or Short Circuit In Knock Sensor Signal
53	Knock Control In ECU Is Faulty
71	EGR Gas Below Predetermined Level During EGR Control
(1) The throttle position sensor, neutral safety switch and A/C Signal circuits are monitored.

(1)	The throttle position sensor, neutral safety switch and A/C Signal circuits are monitored.

CODE DIAGNOSTIC HINTS

DIAGNOSTIC CIRCUIT CHECK

CAUTION

Perform all voltage measurements with ECU harness connector installed. Use a high-impedance DVOM (10,000-ohm minimum). Verify battery voltage is greater than 11 volts.

Diagnostic Circuit Check Schematic. Scheme 39

Scheme 39: Diagnostic Circuit Check Schematic

Diagnostic Circuit Check Flow Chart. Scheme 40

Scheme 40: Diagnostic Circuit Check Flow Chart

TEST NO. 1-ECU POWER SOURCE

Terminals	Trouble	Condition	STD Voltage
BATT - E1	No Voltage	All	10 - 14V

TEST NO. 1-ECU POWER SOURCE TROUBLE

Test No. 1 Schematic ECU Power Source. Scheme 41

Scheme 41: Test No. 1 Schematic ECU Power Source

Test No. 1 Flow Chart ECU Power Source. Scheme 42

Scheme 42: Test No. 1 Flow Chart ECU Power Source

TEST NO. 2-ECU (+B) CIRCUIT

Terminals	Trouble	Condition	STD Voltage
+B - E1, +B1 - E1	No Voltage	Ignition Switch ON	10 - 14V

TEST NO. 2-ECU (+B) CIRCUIT TROUBLE

Test No. 2 Schematic ECU (+B) Circuit. Scheme 43

Scheme 43: Test No. 2 Schematic ECU (+B) Circuit

Test No. 2 Flow Chart ECU (+B) Circuit. Scheme 44

Scheme 44: Test No. 2 Flow Chart ECU (+B) Circuit

CODE 14/TEST NO. 3 - IGNITION SIGNAL

Note. To check ignition system components, see I - SYS/COMP TESTS article in the ENGINE PERFORMANCE Section.

Terminals	Trouble	Condition	STD Voltage
IGT - E1	No Voltage	Idling	0.7 - 1.0V

CODE 14/TEST NO. 3-IGNITION SIGNAL TROUBLE

Code 14/Test No. 3 Schematic Ignition Signal. Scheme 45

Scheme 45: Code 14/Test No. 3 Schematic Ignition Signal

Code 14/Test No. 3 Flow Chart Ignition Signal. Scheme 46

Scheme 46: Code 14/Test No. 3 Flow Chart Ignition Signal

Code 21, 27/Test No. 4 Schematic Oxygen Sensor Signal. Scheme 47

Scheme 47: Code 21, 27/Test No. 4 Schematic Oxygen Sensor Signal

Code 21, 27/Test No. 4 Component Diagram Oxygen Sensor Signal. Scheme 48

Scheme 48: Code 21, 27/Test No. 4 Component Diagram Oxygen Sensor Signal

Code 21, 27/Test No. 4 Flow Chart Oxygen Sensor Signal. Scheme 49

Scheme 49: Code 21, 27/Test No. 4 Flow Chart Oxygen Sensor Signal

CODE 22/TEST NO. 5 - COOLANT TEMPERATURE SENSOR SIGNAL

Note. Water temperature sensor is also referred to as coolant temperature sensor.

Terminals	Trouble	Condition	STD Voltage
THW - E2	No Voltage	Ignition Switch ON Coolant Temp. 80°C (176°F)	0.1 - 1.0V

CODE 22/TEST NO. 5-CTS SENSOR SIGNAL TROUBLE

Code 22/Test No. 5 Schematic Coolant Temperature Sensor Signal. Scheme 50

Scheme 50: Code 22/Test No. 5 Schematic Coolant Temperature Sensor Signal

Code 22/Test No. 5 Flow Chart Coolant Temperature Sensor Signal. Scheme 51

Scheme 51: Code 22/Test No. 5 Flow Chart Coolant Temperature Sensor Signal

CODE 24/TEST NO. 6 - INTAKE AIR TEMPERATURE SENSOR SIGNAL

Terminals	Trouble	Condition	STD Voltage
THA - E2	No Voltage	Ignition Switch ON Int. Air Temp. 20°C (68°F)	1 - 3V

CODE 24/TEST NO. 6-IAT SENSOR SIGNAL TROUBLE

Code 24/Test No. 6 Schematic Intake Air Temperature Sensor Signal. Scheme 52

Scheme 52: Code 24/Test No. 6 Schematic Intake Air Temperature Sensor Signal

Code 24/Test No. 6 Flow Chart Intake Air Temperature Sensor Signal. Scheme 53

Scheme 53: Code 24/Test No. 6 Flow Chart Intake Air Temperature Sensor Signal

CODE 31, 32/TEST NO. 7 - AIRFLOW METER SIGNAL

Terminals	Trouble	Condition	STD Voltage
VC - E2	No Voltage	All	4 - 6V
VS - E2	"	Ignition Switch ON Measuring Plate CLOSED	3.7 - 4.3V
VS - E2	"	Ignition Switch ON Measuring Plate OPEN	0.2 - 0.5V
VS - E2	"	Idling	1.6 - 4.1V
VS - E2	"	3000 RPM	1.0 - 2.0V

CODE 31,32/TEST NO. 7-AIRFLOW METER SIGNAL TROUBLE

Code 31, 32/Test No. 7 Schematic Airflow Meter Signal. Scheme 54

Scheme 54: Code 31, 32/Test No. 7 Schematic Airflow Meter Signal

Code 31, 32/Test No. 7 Flow Chart Airflow Meter Signal. Scheme 55

Scheme 55: Code 31, 32/Test No. 7 Flow Chart Airflow Meter Signal

CODE 41/TEST NO. 8 - TPS SENSOR SIGNAL (W/O ECT)

Terminals	Trouble	Condition	STD Voltage
IDL - E1	No Voltage	Ignition Switch ON Throttle Valve OPEN	8 - 14V
PSW - E1	No Voltage	Ignition Switch ON Throttle Valve Fully CLOSED	4 - 6V

CODE 41/TEST NO. 8-TPS SENSOR SIGNAL TROUBLE

Code 41/Test No. 8 Schematic (W/O Elect. Controlled Trans.) Throttle Position Sensor Signal. Scheme 56

Scheme 56: Code 41/Test No. 8 Schematic (W/O Elect. Controlled Trans.) Throttle Position Sensor Signal

Code 41/Test No. 8 Flow Chart (W/O Elect. Controlled Trans.) Throttle Position Sensor Signal. Scheme 57

Scheme 57: Code 41/Test No. 8 Flow Chart (W/O Elect. Controlled Trans.) Throttle Position Sensor Signal

CODE 41/TEST NO. 8 - TPS SENSOR SIGNAL (W/ECT)

Terminals	Trouble	Condition	STD Voltage
IDL - E2	No Voltage	IG SW ON-Throttle valve OPEN	8 - 14V
VC - E2	"	IG SW ON	4 - 6V
VTA - E2	"	IG SW ON-Throttle valve SHUT	0.1 - 1.0V
"	"	IG SW ON-Throttle valve OPEN	4 - 6V

CODE 41/TEST NO. 8-TPS SENSOR SIGNAL TROUBLE

Code 41/Test No. 8 Schematic (W/ECT) Throttle Position Sensor Signal. Scheme 58

Scheme 58: Code 41/Test No. 8 Schematic (W/ECT) Throttle Position Sensor Signal

Code 41/Test No. 8 Flow Chart (W/ECT)-Terminals IDL - E2 Throttle Position Sensor Signal. Scheme 59

Scheme 59: Code 41/Test No. 8 Flow Chart (W/ECT)-Terminals IDL - E2 Throttle Position Sensor Signal

Code 41/Test No. 8 Flow Chart (W/ECT)-Terminals VC - E2 Throttle Position Sensor Signal. Scheme 60

Scheme 60: Code 41/Test No. 8 Flow Chart (W/ECT)-Terminals VC - E2 Throttle Position Sensor Signal

Code 41/Test No. 8 Flow Chart (W/ECT)-Terminals VTA - E2 Throttle Position Sensor Signal. Scheme 61

Scheme 61: Code 41/Test No. 8 Flow Chart (W/ECT)-Terminals VTA - E2 Throttle Position Sensor Signal

CODE 43/TEST NO. 9 - STARTER SIGNAL

Terminal	Trouble	Condition	STD Voltage
STA-E1	No Voltage	Cranking	6-14V

CODE 43/TEST NO. 9-STARTER SIGNAL TROUBLE

Code 43/Test No. 9 Schematic Starter Signal. Scheme 62

Scheme 62: Code 43/Test No. 9 Schematic Starter Signal

Code 43/Test No. 9 Component Diagram Starter Signal. Scheme 63

Scheme 63: Code 43/Test No. 9 Component Diagram Starter Signal

Code 43/Test No. 9 Flow Chart Starter Signal. Scheme 64

Scheme 64: Code 43/Test No. 9 Flow Chart Starter Signal

TEST NO. 12 - INJECTOR CIRCUIT

Terminal	Trouble	Condition	STD Voltage
No. 10-E01	No Voltage	Ignition Switch On	10-14V
No. 20-E02	No Voltage	"	"

TEST NO. 12-INJECTOR CIRCUIT TROUBLE

Test No. 12 Schematic Injector Circuit. Scheme 65

Scheme 65: Test No. 12 Schematic Injector Circuit

Test No. 12 Flow Chart Injector Circuit. Scheme 66

Scheme 66: Test No. 12 Flow Chart Injector Circuit

TEST NO. 13 - IDLE SPEED CONTROL CIRCUIT

Terminal	Trouble	Condition	STD Voltage
ISC1-E1	No Voltage	Ignition Switch ON	9-14V
ISC2-E1	"	"	"

TEST NO. 13-IDLE SPEED CONTROL CIRCUIT TROUBLE

Test No. 13 Schematic Idle Speed Control Circuit. Scheme 67

Scheme 67: Test No. 13 Schematic Idle Speed Control Circuit

Test No. 13 Component Diagram Idle Speed Control Circuit. Scheme 68

Scheme 68: Test No. 13 Component Diagram Idle Speed Control Circuit

Test No. 13 Flow Chart Idle Speed Control Circuit. Scheme 69

Scheme 69: Test No. 13 Flow Chart Idle Speed Control Circuit

TEST NO. 14 - CHECK ENGINE LIGHT CIRCUIT

Terminal	Trouble	Condition	STD Voltage
W-E1	No Voltage	No Trouble (Check Engine Light OFF) and Engine Running	10-14V

TEST NO. 14-CHECK ENGINE LIGHT CIRCUIT TROUBLE

Test No. 14 Schematic Check Engine Light Circuit. Scheme 70

Scheme 70: Test No. 14 Schematic Check Engine Light Circuit

Test No. 14 Flow Chart Check Engine Light Circuit. Scheme 71

Scheme 71: Test No. 14 Flow Chart Check Engine Light Circuit

Engine Controls - Tests W/codes - 4-CYL: Diagnosis Toyota Camry XV10