RETRIEVING TROUBLE CODES
Note. Trouble codes may be retrieved using Toyota scan tester in Normal Mode or Test Mode.
Note. Normal Mode is used to retrieve trouble code from Electronic Control Module (ECM) to determine problem area. Test Mode is used to check for trouble codes when operating vehicle to simulate conditions in which trouble code was set. Test mode contains a higher sensing ability to detect malfunctions. Test Mode helps determine malfunctions caused by poor electrical connections, which are difficult to determine using Normal Mode. Test Mode also checks for malfunction in starter signal circuit, A/C switch signal and Park/Neutral switch signal.
Note. The Malfunction Indicator Light (MIL) on the instrument panel may also be referred to as CHECK ENGINE light.
Test Mode
- Before retrieving trouble code(s), verify MIL on instrument panel comes on with ignition on and engine off. The MIL should go off when engine is started.
- Check bulb circuit on instrument panel and wiring circuit between MIL and ECM. See appropriate wiring diagram information in «WIRING DIAGRAMS»(ref-21402) article. See «ECM LOCATION»(ref-21403-S12958542212001010300000).
- Ensure battery voltage is greater than 11 volts and charging system is okay. Apply parking brake. Shift the transmission/transaxle to Neutral (M/T) or Park (A/T). Turn A/C and all accessories off. Ensure throttle is in idle position and ignition is off. NOTE: Test Mode will not operate if jumper wire is installed between terminals TE2 and E1 in Data Link Connector (DLC) after ignition is turned on.
- Install Jumper Wire (SST 09843-18020) between terminals TE2 and E1 in Data Link Connector (DLC) with ignition off. (Scheme 79) NOTE: DLC No. 2 is used. (Scheme 79)
- Turn ignition on with engine off. Test Mode is operational if MIL on instrument panel flashes.
- If MIL fails to flash, check TE2 wiring circuit. See appropriate TE1 & TE2 DIAGNOSTIC CIRCUIT CHECK chart under «TROUBLE CODE CHARTS»(ref-21403-S01176785342001010300000). See «ECM LOCATION»(ref-21403-S12958542212001010300000).
- Drive vehicle at a speed greater than 6 MPH. ECM will set Trouble Codes 42 and 43 if vehicle is not driven. Try to simulate conditions of driveability complaint described by customer, and note when MIL comes on. This indicates when problem exists.
- Stop vehicle, but DO NOT turn engine off. Install jumper wire between terminals TE1 and E1 in DLC. (Scheme 79) Count number of flashes from MIL on instrument panel. If system is operating properly (with no trouble codes), MIL will flash continuously and evenly. (Scheme 80)
- 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. (Scheme 80)
- 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. Trouble codes are displayed in order of smallest to largest. NOTE: Trouble Code 51 will normally be displayed if automatic transmission/transaxle is in any gear except Park or Neutral, A/C is turned on, or accelerator pedal is depressed.
- After trouble code(s) is retrieved, remove jumper wires to exit Test Mode. See «NOTES ON TROUBLE CODES»(ref-21403-S38630100362001010300000). For additional information on trouble codes, see «TROUBLE CODE DIAGNOSTIC HINTS»(ref-21403-S11590933412001010300000) table under SELF-DIAGNOSTIC SYSTEM and appropriate «TROUBLE CODE IDENTIFICATION»(ref-21403-S24655206452001010300000) table under TROUBLE CODE IDENTIFICATION.
Note. The MIL may not come on if certain trouble code is set when in Test Mode. See appropriate TROUBLE CODE IDENTIFICATION table under TROUBLE CODE IDENTIFICATION.
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 .
Scheme 79
Scheme 80
NOTES ON TROUBLE CODES
- When certain trouble codes occur, MIL on instrument panel will not come on. For designation of MIL operation on certain trouble codes, see appropriate «TROUBLE CODE IDENTIFICATION»(ref-21403-S24655206452001010300000) table under TROUBLE CODE IDENTIFICATION.
- When certain malfunctions or trouble codes initially occur, they will be temporarily stored in ECM memory, but MIL on instrument panel will not come on.
- The second time malfunction or trouble code is detected, MIL on instrument panel will then come on, provided ignition is turned off and then back on after malfunction or trouble code was first detected. This is referred to as the Two Trip Detection Logic and only applies to specified trouble codes. See «TWO TRIP DETECTION LOGIC TROUBLE CODES»(ref-21403-S36138554852001010300000) table. NOTE: When road testing vehicle in Test Mode, the Two Trip Detection Logic will not function. In Test Mode, the MIL on instrument panel will come on the first time malfunction or trouble code is detected. TWO TRIP DETECTION LOGIC TROUBLE CODES (2) Application (1) Trouble Code Non-Turbo 21, 25, 26, 27, 28, 71 & 78 (1) Trouble codes may not apply to all models, as some trouble codes are used only on Calif. models. (2) Two Trip Detection Logic is used on Trouble Code 21 on all except Calif. models.
- In Normal Mode, MIL on instrument panel will go off after malfunction is repaired, but trouble codes, except ECM non-memory trouble codes, will be retained in ECM memory until cleared. ECM non-memory trouble codes are not stored in ECM memory. See «ECM NON-MEMORY TROUBLE CODES»(ref-21403-S10411712312001010300000) table.
- In Test Mode, all trouble codes except ECM non-memory trouble codes are retained in ECM memory, even with ignition off and repairs made, until cleared. ECM non-memory trouble codes are not retained in ECM memory. See «ECM NON-MEMORY TROUBLE CODES»(ref-21403-S10411712312001010300000) table.
Note. When in Test Mode, if vehicle is not driven at a speed greater than 6 MPH, ECM will set Trouble Codes 42 and 43. For MIL operation in relation to trouble code when in Test Mode, see appropriate TROUBLE CODE IDENTIFICATION table under TROUBLE CODE IDENTIFICATION.
| Application | Trouble Code |
|---|---|
| Normal Mode | 16, 43, 51 & 53 |
| Test Mode | 43 & 51 |
ECM NON-MEMORY TROUBLE CODES
CLEARING TROUBLE CODES
- 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 APPLICATION»(ref-21403-S26398898462001010300000) table and «FUSE/RELAY BOX LOCATION»(ref-21403-S37375230642001010300000) table.
- Depending on ambient temperature, fuse may need to be removed for more than 30 seconds, especially in colder temperatures. Install fuse. Road test vehicle. Ensure system operates properly (with no trouble codes) and MIL flashes continuously and evenly. (Scheme 80) 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.
- With certain trouble codes, once trouble code has been cleared from ECM memory, a trouble code detection driving pattern test can be performed to verify repairs and that trouble has not reset. For information on trouble code detection driving pattern test, see «TROUBLE CODE DETECTION DRIVING PATTERN TESTS»(ref-21403-S17093565152001010300000).
| Model | Fuse (Amps) |
|---|---|
| Supra | EFI No. 1 (30) |
FUSE APPLICATION
| Application | Location |
|---|---|
| Supra | Driver Side, Front Corner Of Engine Bay |
FUSE/RELAY BOX LOCATION
TROUBLE CODE DETECTION DRIVING PATTERN TESTS
Note. Trouble code driving pattern test may be referred to as driving pattern test.
- With certain trouble codes, once trouble code has been cleared from ECM memory, a trouble code detection driving pattern test can be performed to verify repairs and that trouble has not reset. Trouble code driving pattern test will duplicate conditions required to set specified trouble codes.
- Trouble code detection driving pattern test lists procedure to be performed to ensure trouble code has not reset. (Scheme 81)
- Trouble code detection driving pattern tests apply only to specified trouble codes. See «TROUBLE CODE DETECTION DRIVING PATTERN TEST APPLICATION»(ref-21403-S08029631122001010300000) table. Trouble code detection driving pattern test will be included with proper trouble code chart under «TROUBLE CODE CHARTS»(ref-21403-S01176785342001010300000).
| Model | (1) Trouble Code |
|---|---|
| Non-Turbo | 21, 25, 26, 27, 28, 52, 53, 55 & 71 |
| (1) Trouble codes listed may not apply to all models, as some Trouble codes are used only on Calif. models. | |
| (1) | Trouble codes listed may not apply to all models, as some Trouble codes are used only on Calif. models. |
TROUBLE CODE DETECTION DRIVING PATTERN TEST APPLICATION
Scheme 81
TROUBLE CODE DIAGNOSTIC HINTS
Note. To determine a common cause for a trouble code to be set, see TROUBLE CODE DIAGNOSTIC HINTS table.
| Trouble Code | Diagnostic Hints |
|---|---|
| 12 | No "G", "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 Open In "G-" Circuit |
| 13 | No "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 600-4000 RPM |
| 14 | No "IG" Or "IGF" Ignition Signal To ECM From Ignitor Several Times In Succession |
| 16 | Fault In Transmission/Transaxle ECU Or ECM |
| 21 | Defective O2 Sensor, Open Or Short Circuit In O2 Sensor Signal |
| 22 | Open Or Short Circuit In Engine 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 O2 Sensor, Open Or Short Circuit In O2 Sensor Signal |
| 31 | Open Or Short Circuit In Airflow Meter Or MAP Sensor Signal |
| 32 | Open Or Short Circuit Between Airflow Meter Terminals |
| 41 | Open Or Short Circuit In Throttle Position Sensor Signal |
| 42 | No Signal From Vehicle Speed Sensor For Several Seconds |
| 43 | No "STA" Signal To ECM Until Engine Reaches 800 RPM With Engine Cranking |
| 47 | Open Or Short Circuit In Sub-Throttle Position Sensor Signal |
| 51 | (2) Problem In One Of 3 Circuits Monitored By ECM |
| 52 | Open Or Short Circuit In Knock Sensor Signal |
| 53 | Knock Control In ECM Is Faulty |
| 55 | Open Or Short Circuit In Knock Sensor Signal |
| 71 | EGR Gas Temp. Less Than Predetermined Level During EGR Control |
| 78 | Open Or Short Circuit In Fuel Pump Control Circuit Or Fuel Pump Electronic Control Unit (ECU) |
| 81 | Open In ECT1 Circuit Between ECM & Trans. Control Module (TCM) For At Least 2 Seconds |
| 83 | Open In ESA1 Circuit Between ECM & Trans. Control Module (TCM) For 1/2 Second After Engine Idles At Least 1/2 Second |
| 84 | Open In ESA2 Circuit Between ECM & Trans. Control Module (TCM) For 1/2 Second After Engine Idles At Least 1/2 Second |
| 85 | Open In ESA3 Circuit Between ECM & Trans. 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 (1)
DTC 13 - RPM SIGNAL
| DTC No. | Detecting Condition(s) | Trouble Area |
|---|---|---|
| 13 | No NE signal to ECM for 0.3 sec. or more at 1,500 RPM or more. | Open/Short in NE circuit. |
| " | No G signal to ECM while NE signal is input 4 times to ECM when engine speed is between 500 RPM and 4000 RPM. | IIA, ECM |
DTC 13 - RPM SIGNAL TROUBLE SHOOTING
Code 13 indicates a momentary interruption in the "G" or "NE" signal from distributor to ECM has occurred, but has returned to normal. Although problem may not be present at time of inspection, it cannot be ignored because trouble code has been set, indicating a malfunction has occurred at one time in the "G" or "NE" signal circuit. Check distributor connector and "NE" terminal of ECM connector for the following
- Loose Connectors
- Dirty Connector Terminals
- Loose Connector Terminals
Scheme 82
Scheme 83
Scheme 84
Scheme 85
DTC 16 - ELECTRONIC-CONTROLLED A/T SIGNAL
The signal from the A/T CPU retards the ignition timing of the engine during A/T gear shifting, thus momentarily reducing torque output of the engine for smooth clutch operation inside the transmission and reduced shift check.
| DTC No. | Detecting Condition(s) | Trouble Area |
|---|---|---|
| 16 | Fault in communications between engine CPU and A/T CPU in the ECM | ECM |
DTC 16 - ELECTRONIC-CONTROLLED A/T SIGNAL TROUBLE SHOOTING
If the ECM records the diagnostic trouble code "16", it prohibits the torque control of the A/T which performs smooth gear shifting.
Scheme 86
Scheme 87
Scheme 88
Scheme 89
Scheme 90
Scheme 91
Scheme 92
Scheme 93
Scheme 94
Scheme 95
Scheme 96
Scheme 97
Scheme 98
Scheme 99
Scheme 100
Scheme 101
DTC 35 - BAROMETRIC PRESSURE SENSOR SIGNAL
The BARO sensor is built into the ECM. This is a semiconductor pressure sensor with properties which cause its electrical resistance to change when stress is applied to the sensor's crystal (silicon) (piezoelectric) effect. This sensor is used to detect the atmospheric (absolute) pressure and outputs corresponding electrical signals. Fluctuations in the air pressure cause changes in the intake air density, which can cause deviations in the air-fuel ratio. The signals from the BARO sensor are used to make corrections for these fluctuations. If ECM detects diagnostic trouble code "35", the fail safe function operates and the atmospheric pressure is set at a constant 101.3 kPa (760 mmHg, 29.92 in.Hg).
| DTC No. | Detecting Condition(s) | Trouble Area |
|---|---|---|
| 35 | Open or short in BARO sensor circuit for 0.5 seconds or more | ECM |
DTC 35 - BARO SENSOR TROUBLE SHOOTING
