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Home/Toyota/Paseo/Toyota Paseo L40 (1991-1996)/Repair manual/Testing & Diagnostics/Engine Controls - Tests W/codes: Diagnosis
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Engine Controls - Tests W/codes: Diagnosis Toyota Paseo L40

Testing & Diagnostics 31 illustrations ~844 words

RETRIEVING TROUBLE CODES

Note. On all models, Normal Mode is used to retrieve trouble code from ECM to determine problem area. Paseo self-diagnostics system does not have Test Mode.

Note. The Malfunction Indicator Light (MIL) on the instrument panel may also be referred to as CHECK ENGINE light.

Test Mode

Note. Test Mode is not available on Paseo.

Scheme 1

Scheme 1: Test Mode
Scheme 1: Test Mode

Scheme 2

Scheme 2
Scheme 2

NOTES ON TROUBLE CODES

  1. No other trouble code will appear with Trouble Code 11.
  2. On various models when certain trouble codes occur, MIL on instrument panel will not come on. For designation of MIL operation on certain trouble codes, see appropriate table under «TROUBLE CODE IDENTIFICATION»(ref-21197-S20646677722001010300000) .
  3. On various models when certain trouble codes initially occur, they will be temporarily stored in ECM memory, but MIL on instrument panel will not come on.
  4. The second time trouble code is detected, MIL on instrument panel will then come on. This is referred to as the 2 trip detection logic and only applies to specified trouble codes. See «DETECTION LOGIC TROUBLE CODES»(ref-21197-S09566724872001010300000) table. DETECTION LOGIC TROUBLE CODES Application Trouble Code Paseo 21, 25, 26 & 71
  5. In Normal Mode, MIL on instrument panel will go off after malfunction is repaired, but trouble codes, except ECM non-memory codes, will be retained in ECM memory until cleared. ECM non-memory codes are not stored in ECM memory. See «ECM NON-MEMORY TROUBLE CODES»(ref-21197-S27657264522001010300000) table.

Note. Test Mode is not used on Paseo.

ApplicationTrouble Code
Normal Mode Only51

ECM NON-MEMORY TROUBLE CODES

CLEARING TROUBLE CODES

  1. After performing repairs, clear ECM memory of all stored trouble codes. To clear memory, turn ignition off. Remove proper fuse from fuse/relay box for approximately 30 seconds or more. See «FUSE/RELAY BOX LOCATION»(ref-21197-S34968463412001010300000) table. See «FUSE APPLICATION»(ref-21197-S24821234672001010300000) table to remove proper fuse.
  2. Depending on ambient temperature, fuse may need to be removed for more than 30 seconds in colder temperatures. Install fuse. Road test vehicle, and ensure system operates properly. (Scheme 2)

Note. Trouble codes may also be cleared by disconnecting negative battery cable. However, other memory functions (clock, radio, alarm, seats, etc.) will be cancelled and must be reset.

ApplicationLocation
PaseoDriver Side, Front Corner Of Engine Bay

FUSE/RELAY BOX LOCATION

ModelFuse (Amperage)
PaseoEFI (15)

FUSE APPLICATION

TROUBLE CODE DIAGNOSTIC HINTS

Trouble Code(1) Diagnostic Hints
12No "G1", "G2" or "NE" Ignition Signal To ECM Within 2 Seconds After Engine Is Cranked, No "G" Ignition Signal To ECM For 3 Seconds With Engine Speed Of 600-4000 RPM
13No "NE" Ignition Signal To ECM When Engine Speed Is Greater Than Approximately 1000 RPM, No "G" Ignition Signal To ECM When "NE" Signal Is Input 4 Times With Engine Speed Of 500-4000 RPM
14No "IG" Or "IGF" Ignition Signal To ECM From Ignitor Several Times In Succession
16Fault In Transmission/Transaxle ECU Or ECM
21Defective Main O2 Sensor, Open Or Short Circuit In Main O2 Sensor Signal
22Open Or Short Circuit In Coolant Temp. Sensor Signal
24Open Or Short Circuit In Intake Air Temp. Sensor Signal
25Lean Signal Sent By O2 Sensor For Several Seconds
26Rich Signal Sent By O2 Sensor For Several Seconds
27Open Or Short Circuit In Sub-O2 Sensor Signal
28Defective O2 Sensor, Open Or Short Circuit In O2 Sensor Signal
31Open Or Short Circuit In Airflow Meter, MAP Sensor Or Vacuum Sensor Signal
32Open Or Short Circuit Between Airflow Meter Terminals
41Open Or Short Circuit In Throttle Position Sensor Signal
42No Signal From Vehicle Speed Sensor For Several Seconds
43No "STA" Signal To ECM Until Engine Reaches 800 RPM With Engine Cranking
47Open Or Short Circuit In Sub-Throttle Position Sensor Signal
51(2) Problem In One Of 3 Circuits Monitored By ECM
52Open Or Short Circuit In Knock Sensor Signal
53Knock Control In ECM Is Faulty
55Open Or Short Circuit In Knock Sensor Signal
71EGR Gas Temperature Less Than Predetermined Level During EGR Control
78Open Or Short Circuit In Fuel Pump Control Circuit Or Fuel Pump Electronic Control Unit (ECU)
81Open In ECT1 Circuit Between ECM & Transmission Control Module (TCM) For At Least 2 Seconds
83Open In ESA1 Circuit Between ECM & Transmission Control Module (TCM) For 1/2 Second After Engine Idles At Least 1/2 Second
84Open In ESA2 Circuit Between ECM & Transmission Control Module (TCM) For 1/2 Second After Engine Idles At Least 1/2 Second
85Open In ESA3 Circuit Between ECM & Transmission Control Module (TCM) For 1/2 Second After Engine Idles At Least 1/2 Second
(1) Listed are possible areas causing trouble codes. Not all trouble codes are used on all models. (2) Throttle position sensor, Park/Neutral switch and A/C Signal circuits are monitored.
(1)Listed are possible areas causing trouble codes. Not all trouble codes are used on all models.
(2)Throttle position sensor, Park/Neutral switch and A/C Signal circuits are monitored.

TROUBLE CODE DIAGNOSTIC HINTS

TROUBLE CODE DIAGNOSTIC CHARTS

Note. All schematics and diagnostic flow charts are courtesy of Toyota Motor Sales, U.S.A., Inc.

CAUTIONPerform 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.

ECU Terminal Identification (Auotomatic Transaxle). Scheme 3

Scheme 3: ECU Terminal Identification (Auotomatic Transaxle)
Scheme 3: ECU Terminal Identification (Auotomatic Transaxle)

ECU Terminal Identification (Manual Transaxle). Scheme 4

Scheme 4: ECU Terminal Identification (Manual Transaxle)
Scheme 4: ECU Terminal Identification (Manual Transaxle)

Diagnostic Circuit Check Schematic. Scheme 5

Scheme 5: Diagnostic Circuit Check Schematic
Scheme 5: Diagnostic Circuit Check Schematic

Diagnostic Circuit Check Flow Chart. Scheme 6

Scheme 6: Diagnostic Circuit Check Flow Chart
Scheme 6: Diagnostic Circuit Check Flow Chart

TEST NO. 1 - ECU POWER SOURCE

CAUTIONPerform all voltage measurements with the ECM harness connector installed. Use a high-impedence DVOM (10,000-ohm minimum). Verify that battery voltage is greater than 11 volts.

Test No. 1 Schematic - ECU Power Source. Scheme 7

Scheme 7: Test No. 1 Schematic - ECU Power Source
Scheme 7: Test No. 1 Schematic - ECU Power Source

Test No. 1 Flow Chart - ECU Power Source. Scheme 8

Scheme 8: Test No. 1 Flow Chart - ECU Power Source
Scheme 8: Test No. 1 Flow Chart - ECU Power Source

TEST NO. 2 - ECU (+B) CIRCUIT

TerminalsTroubleConditionSTD Voltage
+B - E1, +B1 - E1No VoltageIgnition Switch ON10 - 14V

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

Test No. 2 Schematic - ECU (+B). Scheme 9

Scheme 9: Test No. 2 Schematic - ECU (+B)
Scheme 9: Test No. 2 Schematic - ECU (+B)

Test No. 2 Flow Chart - ECU (+B). Scheme 10

Scheme 10: Test No. 2 Flow Chart - ECU (+B)
Scheme 10: Test No. 2 Flow Chart - ECU (+B)

CODE 14/TEST NO. 3 - IGNITION SIGNAL

Note. To check ignition system components, see the article SYSTEM/COMPONENT TESTS in this section.

TerminalsTroubleConditionSTD Voltage
IGT - E1No VoltageCranking or Idling(Fluctuate) 0.5V or Less <--> 4.5-5.5V

CODE 14/TEST NO. 3 - IGNITION SIGNAL TROUBLE

Code 14/Test No. 3 Schematic - Ignition Signal. Scheme 11

Scheme 11: Code 14/Test No. 3 Schematic - Ignition Signal
Scheme 11: Code 14/Test No. 3 Schematic - Ignition Signal

Code 14/Test No. 3 Flow Chart - Ignition Signal. Scheme 12

Scheme 12: Code 14/Test No. 3 Flow Chart - Ignition Signal
Scheme 12: Code 14/Test No. 3 Flow Chart - Ignition Signal

Code 21 Schematic - Oxygen Sensor Signal. Scheme 13

Scheme 13: Code 21 Schematic - Oxygen Sensor Signal
Scheme 13: Code 21 Schematic - Oxygen Sensor Signal

Code 21 Flow Chart - Oxygen Sensor Signal. Scheme 14

Scheme 14: Code 21 Flow Chart - Oxygen Sensor Signal
Scheme 14: Code 21 Flow Chart - Oxygen Sensor Signal

CODE 22/TEST NO. 4 - COOLANT TEMPERATURE SENSOR (CTS) SIGNAL

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

TerminalsTroubleConditionSTD Voltage
THW - E2No VoltageIgnition Switch ON Coolant Temp. 80°C (176°F)0.1 - 0.8V

CODE 22/TEST NO. 4 - CTS SENSOR SIGNAL TROUBLE

Code 22/Test No. 4 Schematic - CTS Signal. Scheme 15

Scheme 15: Code 22/Test No. 4 Schematic - CTS Signal
Scheme 15: Code 22/Test No. 4 Schematic - CTS Signal

Code 22/Test No. 4 Flow Chart - CTS Signal. Scheme 16

Scheme 16: Code 22/Test No. 4 Flow Chart - CTS Signal
Scheme 16: Code 22/Test No. 4 Flow Chart - CTS Signal

CODE 24/TEST NO. 5 - INTAKE AIR TEMPERATURE (IAT) SENSOR SIGNAL

TerminalsTroubleConditionSTD Voltage
THA - E2No VoltageIgnition Switch ON Int. Air Temp. 20°C (68°F)0.1 - 0.8V

CODE 24/TEST NO. 5-IAT SENSOR SIGNAL TROUBLE

Code 24/Test No. 5 Schematic - IAT Sensor. Scheme 17

Scheme 17: Code 24/Test No. 5 Schematic - IAT Sensor
Scheme 17: Code 24/Test No. 5 Schematic - IAT Sensor

Code 24/Test No. 5 Flow Chart - IAT Sensor. Scheme 18

Scheme 18: Code 24/Test No. 5 Flow Chart - IAT Sensor
Scheme 18: Code 24/Test No. 5 Flow Chart - IAT Sensor

CODE 31/TEST NO. 6 - VACUUM SENSOR SIGNAL

TerminalTroubleConditionSTD Voltage
PIM-E2No VoltageIgnition Switch ON3.3-3.9V
VCC-E2No VoltageIgnition Switch ON4.5-5.5V

CODE 31/TEST NO. 6 - VACUUM SENSOR SIGNAL TROUBLE

Code 31/Test No. 6 Schematic - Vacuum Sensor. Scheme 19

Scheme 19: Code 31/Test No. 6 Schematic - Vacuum Sensor
Scheme 19: Code 31/Test No. 6 Schematic - Vacuum Sensor

Code 31/Test No. 6 Flow Chart - Vacuum Sensor. Scheme 20

Scheme 20: Code 31/Test No. 6 Flow Chart - Vacuum Sensor
Scheme 20: Code 31/Test No. 6 Flow Chart - Vacuum Sensor

CODE 41/TEST NO. 7 - THROTTLE POSITION SENSOR (TPS) SIGNAL

TerminalTroubleConditionSTD Voltage
IDL-E2No VoltageIgn. Sw. ON-Throttle Valve (TV) Open4.5-5.5V
VCC-E2"Ignition ON4.5-5.5V
VTA-E2"Ignition Switch ON - TV Fully Closed0.8-1.2V
""Ignition Switch ON - TV Fully Open3.2-4.2V

CODE 41/TEST NO. 7 - TPS SENSOR TROUBLE

Code 41/Test No. 7 Schematic - TPS. Scheme 21

Scheme 21: Code 41/Test No. 7 Schematic - TPS
Scheme 21: Code 41/Test No. 7 Schematic - TPS

Code 41/Test No. 7 Flow Chart-Terminals IDL-E2 - TPS. Scheme 22

Scheme 22: Code 41/Test No. 7 Flow Chart-Terminals IDL-E2 - TPS
Scheme 22: Code 41/Test No. 7 Flow Chart-Terminals IDL-E2 - TPS

Code 41/Test No. 7 Flow Chart-Terminals VCC-E2 - TPS. Scheme 23

Scheme 23: Code 41/Test No. 7 Flow Chart-Terminals VCC-E2 - TPS
Scheme 23: Code 41/Test No. 7 Flow Chart-Terminals VCC-E2 - TPS

Code 41/Test No. 7 Flow Chart-Terminals VTA-E2 - TPS. Scheme 24

Scheme 24: Code 41/Test No. 7 Flow Chart-Terminals VTA-E2 - TPS
Scheme 24: Code 41/Test No. 7 Flow Chart-Terminals VTA-E2 - TPS

CODE 43/TEST NO. 8 - STARTER SIGNAL

TerminalTroubleConditionSTD Voltage
STA-E1No VoltageCranking6-14V

CODE 43/TEST NO. 8 - STARTER SIGNAL TROUBLE

Code 43/Test No. 8 Schematic - Starter Signal. Scheme 25

Scheme 25: Code 43/Test No. 8 Schematic - Starter Signal
Scheme 25: Code 43/Test No. 8 Schematic - Starter Signal

Code 43/Test No. 8 Component Diagram - Starter Signal. Scheme 26

Scheme 26: Code 43/Test No. 8 Component Diagram - Starter Signal
Scheme 26: Code 43/Test No. 8 Component Diagram - Starter Signal

Code 43/Test No. 8 Flow Chart - Starter Signal. Scheme 27

Scheme 27: Code 43/Test No. 8 Flow Chart - Starter Signal
Scheme 27: Code 43/Test No. 8 Flow Chart - Starter Signal

TEST NO. 9 - INJECTOR CIRCUIT

TerminalTroubleConditionSTD Voltage
No. 10, & 20 to E01 & E02No VoltageIgnition Switch ON10-14V

TEST NO. 9 - INJECTOR CIRCUIT TROUBLE

Test No. 9 Schematic - Injector Circuit. Scheme 28

Scheme 28: Test No. 9 Schematic - Injector Circuit
Scheme 28: Test No. 9 Schematic - Injector Circuit

Test No. 9 Flow Chart - Injector Circuit. Scheme 29

Scheme 29: Test No. 9 Flow Chart - Injector Circuit
Scheme 29: Test No. 9 Flow Chart - Injector Circuit

TEST NO. 10 - MALFUNCTION INDICATOR LIGHT (MIL) CIRCUIT

TerminalTroubleConditionSTD Voltage
W - E1No VoltageNo trouble (MIL off, engine running)10-14V

TEST NO. 10 - MIL CIRCUIT TROUBLE

Test No. 10 Schematic - MIL Circuit. Scheme 30

Scheme 30: Test No. 10 Schematic - MIL Circuit
Scheme 30: Test No. 10 Schematic - MIL Circuit

Test No. 10 Flow Chart - MIL Circuit. Scheme 31

Scheme 31: Test No. 10 Flow Chart - MIL Circuit
Scheme 31: Test No. 10 Flow Chart - MIL Circuit

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