Engine Controls - Tests W/codes: Other Toyota Tercel L50

TWO-TRIP DETECTION LOGIC

When a malfunction initially occurs, trouble code will be temporarily stored in ECM memory, but MIL on instrument panel will not illuminate. The second time malfunction is detected, MIL on instrument panel will illuminate, provided ignition is turned off and then back on after first malfunction was detected. This is referred to as the Two-Trip Detection Logic.

Note. When road testing vehicle in Check Mode, the Two Trip Detection Logic will not function. Also, MIL will illuminate the first time a malfunction is detected.

DATA LINK CONNECTOR

OBD-II regulations (SAE J-1850) standardizes DLC configurations. DLC3 connector is located in fuse box at lower left of instrument panel. The terminal arrangement of connector complies with SAE J-1962 regulations. (Scheme 44)

Scheme 44

FREEZE-FRAME DATA

The ECM records engine operating condition (fuel system, calculated load, coolant temperature, fuel trim (mixture), engine speed, vehicle speed, etc.) with 1st malfunction ONLY. The information is ONLY for the 1st recorded failure, no matter if more than one code has been recorded. The freeze-frame data is only updated when all codes have been cleared, or a misfire or fuel-trim malfunction has occurred.

Normal Mode Code Retrieval

1. Connect scan tool to Data Link Connector No. 3 (DLC3). (Scheme 44) Turn ignition on. Turn on scan tool. Retrieve any trouble codes stored in memory following scan tool instructions. See the «TROUBLE CODE IDENTIFICATION»(ref-21706-S42398885472001010300000) table.
2. Codes recorded may not have illuminated MIL. When certain malfunctions or trouble codes initially occur, they will be temporarily stored in ECM memory, but MIL will not illuminate.
3. The second time malfunction or trouble code is detected, MIL will illuminate, provided ignition is turned off and then back on after malfunction or trouble code was first detected. This process is referred to as Two Trip Detection Logic and only applies to most trouble codes.
4. Also record freeze-frame data. If using Toyota scan tool, ensure tool is in normal mode. CHECK MODE will erase all codes.

Note. When scan tester is switched from normal mode to check mode, all trouble codes and freeze-frame data will be erased. DO NOT switch modes until all trouble codes and freeze-frame data are recorded.

Check Mode Code Retrieval (Toyota Scan Tester Only)

1. Ensure vehicle battery is fully charged. 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.
2. Connect scan tester to Data Link Connector (DLC) No. 3. (Scheme 44) Turn ignition on with engine off. Turn scan tester on.
3. Switch scan tester from normal mode to check mode. Check mode is operational if MIL on instrument panel flashes. Start engine. Ensure MIL goes off. Try to simulate conditions of driveability complaint described by customer. NOTE: DO NOT turn ignition off until trouble codes and freeze-frame data are recorded. If ignition is turned off, scan tester will switch from check mode to normal mode and all trouble codes and freeze-frame data will be erased.
4. Record any trouble codes and freeze-frame data displayed for system diagnosis. See «TROUBLE CODE IDENTIFICATION»(ref-21706-S42398885472001010300000) table. Information may be useful for determining conditions in which the malfunction occurs.

SUMMARY

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

CODE P0105 - MANIFOLD ABSOLUTE PRESSURE/BAROMETRIC PRESSURE (MAP) SENSOR CIRCUIT

CODE P0106 - MANIFOLD ABSOLUTE PRESSURE/BAROMETRIC PRESSURE (MAP) CIRCUIT RANGE/PERFORMANCE PROBLEM

Note. If Codes P0105 and P0106 are output together, MAP circuit may be open.

Condition

Following conditions continue with engine speed of 400-1000 RPM

1. Closed throttle position switch in ON position.
2. MAP sensor output is 3 volts or less.

CODE P0110 - INTAKE AIR TEMPERATURE (IAT) SENSOR CIRCUIT

CODE P0115 - COOLANT TEMPERATURE SENSOR (CTS) CIRCUIT

Code is set when sensor temperature is 104°F (40°C) or less for at least 20 minutes of engine operation. Possible causes are

1. Coolant temperature sensor.
2. Cooling system.

CODE P0120 - THROTTLE POSITION SENSOR (TPS) CIRCUIT MALFUNCTION

Code is set when ECM consistently detects more than 2 volts from VTA circuit and closed throttle position switch is on. Possible cause is

1. Throttle Position Sensor (TPS).

CODE P0125 - INSUFFICIENT COOLANT TEMPERATURE FOR CLOSED LOOP FUEL CONTROL

CODE P0130 - HEATED OXYGEN SENSOR (FRONT SENSOR) CIRCUIT

Code is set when front oxygen sensor voltage remains at .40-.55 volt during idle, once engine is at normal operating temperature. Possible causes are

1. Heated oxygen sensor.
2. Fuel trim malfunction.

Code is set when ECM detects a response time of 1 second or more from sensor to change from rich to lean, or lean to rich. Possible cause is heated oxygen sensor.

CODE P0135 - HEATED OXYGEN SENSOR (FRONT SENSOR) CIRCUIT

Code is set when either of the following conditions is present

* Sensor heater current draw exceeds 2 amps, or voltage drop of circuit exceeds 5 volt.

* Sensor heater current draw is .25 amps or less.

Possible causes are

1. Heated oxygen sensor open or short circuit.
2. Heated oxygen sensor heater.
3. ECM.

Code is set when right side oxygen sensor voltage remains at .40-.55 volt during vehicle operation (31 MPH or more), once engine is at normal operating temperature. Possible causes are

1. Heated oxygen sensor.

CODE P0141 - HEATED OXYGEN SENSOR (REAR SENSOR) CIRCUIT

See CODE P0135 - HEATED OXYGEN SENSOR (FRONT SENSOR) CIRCUIT.

CODE P0170 - FUEL TRIM MALFUNCTION

CODES P0301-P0304 - CYLINDERS NO. 1-4 MISFIRE DETECTED

Note. When 2 or more codes for a misfiring cylinder are recorded repeatedly, but Code P0300 is not recorded, it indicates that misfires were detected and stored into ECM memory at different times.

Two conditions can cause code to set. These are

1. During any particular 200 revolutions of engine, misfiring is detected which can cause catalytic converter overheating and/or damage.
2. During any particular 1000 revolutions of engine, misfiring is detected which can cause a deterioration in emission levels.

CODE P0325 - KNOCK SENSOR NO. 1 CIRCUIT

CODE P0335 - CRANKSHAFT POSITION (CKP) SENSOR "A" CIRCUIT

CODE P0340 - CAMSHAFT POSITION (CMP) SENSOR CIRCUIT

CODE P0401 - INSUFFICIENT EXHAUST GAS RECIRCULATION (EGR) FLOW DETECTED

CODE P0402 - EXCESSIVE EXHAUST GAS RECIRCULATION (EGR) FLOW DETECTED

CODE P0500 - VEHICLE SPEED SENSOR MALFUNCTION

CODE P0505 - IDLE CONTROL SYSTEM MALFUNCTION

CODE P0510 - CLOSED THROTTLE POSITION SWITCH MALFUNCTION

CODE P1300 - IGNITOR CIRCUIT MALFUNCTION

CODE P1500 - STARTER SIGNAL CIRCUIT MALFUNCTION

CODE P1600 - ECM BATT MALFUNCTION

CODE P1605 - KNOCK CONTROL CPU MALFUNCTION

CODE P1780 - PARK/NEUTRAL POSITION (PNP) SWITCH

1. PNP switch short circuit.
2. PNP switch.
3. ECM.

Note. Toyota scan tester can be used to confirm PNP switch.