Engine Controls - Tests W/codes: Other Toyota Paseo L40

Hard Failures

Hard failures cause Malfunction Indicator Light (MIL) on instrument panel to illuminate and remain on until problem is repaired. If light comes on and remains on (light may flash) during vehicle operation, corresponding trouble code will be retained in ECM memory on some trouble code applications. Not all trouble codes are retained in ECM memory. The cause of malfunction must be determined using trouble code charts. If a sensor fails, Engine Control Module (ECM) will use a substitute value in its calculations to continue engine operation. In this condition, commonly known as limp-in mode, the vehicle runs but driveability will not be optimum.

Note. The MIL may also be referred to as the CHECK ENGINE light. The MIL may not illuminate when certain failures such as faulty starter signal or A/C switch signal exist, or if certain trouble codes are set.

Intermittent Failures

Intermittent failures may cause Malfunction Indicator Light (MIL) to flicker or illuminate and go out after intermittent fault goes away. However, the corresponding trouble code will be retained in ECM memory on some trouble code applications. Not all trouble codes are retained in ECM memory. Intermittent failures may be caused by a sensor, connector or wiring related problem. See INTERMITTENTS in H - TESTS W/O NO CODES article.

Note. Test Mode (if equipped) and Normal Mode on self-diagnostics system are used for retrieving trouble code from ECM memory for system diagnosis. For information on different mode usage, see RETRIEVING TROUBLE CODES .

Normal Mode

1. Before retrieving trouble code(s), verify MIL on instrument panel light comes on with ignition on and engine off. The MIL light should go off when engine is started.
2. If MIL does not come on, see appropriate DIAGNOSTIC CIRCUIT CHECK chart under TROUBLE CODE CHARTS.
3. If MIL remains on, self-diagnostic system has detected a malfunction or abnormality. Ensure battery voltage is greater than 11 volts and charging system is okay. Warm engine to normal operating temperature.
4. Apply parking brake. Shift transmission/transaxle into Neutral(M/T) or Park (A/T). Turn A/C and all accessories off. Ensure throttle is in idle position.
5. Turn ignition on with engine off. Install Jumper Wire (SST 09843-18020) between terminals TE1 and E1 in Data Link Connector (DLC). see scheme 1 NOTE: Data link connector may be referred to as DLC. Data link connector No. 1 is used on Paseo. see scheme 1
6. Count number of flashes from MIL on instrument panel. If system is operating properly (with no trouble codes), MIL will flash continuously and evenly. see scheme 2 NOTE: If MIL will not flash, check TE1 and E1 wiring circuit. See appropriate DIAGNOSTIC CIRCUIT CHECK chart under TROUBLE CODE DIAGNOSTIC CHARTS.
7. If trouble code exists, digits of trouble code will be flashed at approximately 1/2-second intervals. A 1 1/2-second pause separates first and second digits of code. see scheme 2
8. If more than one trouble code is stored, a 2 1/2-second pause will occur before next trouble code is flashed. Once all trouble codes are displayed, a 4 1/2-second pause will occur then trouble code(s) will be repeated.
9. Trouble codes are displayed in order of smallest to largest. After trouble codes are retrieved, remove jumper wire to exit Normal Mode. See «NOTES ON TROUBLE CODES»(ref-21197-S02624272772001010300000). For additional information on trouble codes, see «TROUBLE CODE DIAGNOSTIC HINTS»(ref-21197-S36285201492001010300000) table under SELF-DIAGNOSTIC SYSTEM and appropriate table under «TROUBLE CODE IDENTIFICATION»(ref-21197-S20646677722001010300000).

Note. To repair failure causing trouble code, refer to proper trouble code chart under TROUBLE CODE CHARTS. Once repairs for trouble code are made, trouble code must be cleared from ECM memory. See CLEARING TROUBLE CODES .

SUMMARY

If no hard trouble codes are present (or only pass trouble codes), driveability symptoms exist or intermittent trouble codes exist, proceed to TESTS W/O CODES article for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.) or intermittent procedures.

Note. To determine a common cause for a trouble code to be set, see TROUBLE CODE DIAGNOSTIC HINTS table below.

CODE 12, 13 - RPM SIGNAL

Code 12 is caused by loss of "G" or "NE" signal from distributor to ECU for at least 2 seconds after starter signal is received at ECU. Check distributor and ignition system components. See I - SYS/COMP TESTS article in this section. Ensure starter signal exists at ECU. See PASEO TEST NO. 9 OR CODE 43.

Code 13 is caused by loss of "NE" signal from distributor to ECU when engine RPM exceeds 1500 RPM. Check distributor and ignition system components. See SYSTEM/COMPONENT TESTS article in this section.

Note. Diagnostic chart for Code 12 or 13 is not available from manufacturer.

Probable Causes

1. Loose Engine Ground
2. Open E1 Circuit
3. Open Injector Circuit
4. Fuel Line Pressure (Blocked Injector)
5. Open Or Short In Oxygen Sensor Or Circuit
6. Ignition System
7. Coolant Temperature Sensor
8. Vacuum Sensor
9. EGR System
10. ECU

Note. For oxygen sensor or circuit testing, see CODE 21 - OXYGEN SENSOR SIGNAL test procedures in this article. For injector or circuit testing, see TEST NO. 9.

Note. Diagnostic chart is not available from manufacturer.

1. Loose Engine Ground
2. Open E1 Circuit
3. Short In Injector Circuit Or Injector
4. Fuel Line Pressure (Leaking Injector)
5. Open Or Short In Oxygen Sensor Or Circuit
6. Open Or Short In Oxygen Sensor Or Circuit
7. Vacuum Sensor
8. Compression Pressure
9. ECU

Note. For oxygen sensor or circuit testing, see CODE 21 - OXYGEN SENSOR SIGNAL test procedures in this article. For injector or circuit testing, see TEST NO. 9.

Note. Diagnostic chart is not available from manufacturer.

1. Open or Short in Vehicle Speed Sensor or Sensor Circuit
2. ECU Defective

Note. Diagnostic chart not available from manufacturer.

1. A/C Switch or Switch Circuit
2. A/C Amplifier
3. Accelerator Pedal or Cable
4. Neutral/Start Switch or Switch Circuit
5. Throttle Position Sensor IDL Circuit
6. ECU

Note. To check throttle position sensor or circuit, see CODE 41/TEST NO. 7 - THROTTLE POSITION SENSOR (TPS) SIGNAL.

Note. To check A/C switch signal, use the following trouble table.

CODE 51 - SWITCH CONDITION SIGNAL TROUBLE

Note. Diagnostic chart not available from manufacturer.

Code 71 Schematic - EGR System Malfunction. Scheme 32

Code 71 Flow Chart - EGR System Malfunction. Scheme 33