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Home >> Toyota >> 1993 >> Tercel Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> Introduction >> Retrieving Trouble Codes >> Test Mode
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Test 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. On all models except Corolla and Supra, if MIL does not come on, see appropriate DIAGNOSTIC CIRCUIT CHECK chart under TROUBLE CODE CHARTS.
  3. On Corolla and Supra, check bulb circuit on instrument panel and wiring circuit between MIL and ECM. See appropriate wiring diagram in WIRING DIAGRAMS article. On Corolla, ECM is located bottom center of dash, in front of console. On Supra, ECM is located below passenger's side of dash, underneath carpet.
  4. On all models, 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.
  5. Install Jumper Wire (SST 09843-18020) between terminals TE2 and E1 in Data Link Connector (DLC) with ignition off. See Fig 1.
    NOTE: DLC No. 1 is used on all models except Camry and Supra. On Camry and Supra, DLC No. 2 is used. See Fig 1.
  6. Turn ignition on with engine off. Test Mode is operational if MIL on instrument panel flashes. If MIL light fails to flash, check TE2 wiring circuit.
    NOTE: On all models except Corolla and Supra, see appropriate wiring diagram in WIRING DIAGRAMS article for TE2 wiring circuit.
  7. On all models, drive vehicle at a speed greater than 6 MPH. The ECM will set Trouble Codes 42 and 43 if vehicle is not driven. Try to simulate conditions of driveability complaint described by the customer and note when MIL comes on. This indicates when the problem exists.
  8. Stop vehicle, but DO NOT  turn engine off. Install jumper wire between terminals TE1 and E1 in data link connector. See Fig 1. 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 Fig 2.
  9. 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 2second digits of code. See Fig 2.
  10. 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: On all models, Trouble Code 51 will normally be displayed if transmission/transaxle is in any gear except Park or Neutral, A/C is turned on, or accelerator pedal is depressed.
  11. After trouble code(s) is retrieved, remove jumper wires to exit Test Mode. See NOTES ON TROUBLE CODES . For additional information on trouble codes, see TROUBLE CODE DIAGNOSTIC HINTS  table under SELF-DIAGNOSTIC SYSTEM and appropriate table under TROUBLE CODE IDENTIFICATION .
NOTE: The MIL may not come on if certain trouble code is set when in Test Mode. See TROUBLE CODE IDENTIFICATION CHARTS.
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 .
Fig 1: Installing Jumper Wire In DLC (Tercel)
G93B79104Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 2: Normal System Operation & Trouble Code I.D. Using MIL
G93E79107Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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