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Diagnostic Code Output

  1. To obtain an output of diagnostic codes, ensure battery voltage is above 11 volts, throttle valve is fully closed, transmission is in "P" or "NEUTRAL" positions, all accessory switches are in "OFF" position, and engine is at normal operating temperature.
  2. Turn ignition switch to "ON" position. DO NOT  start engine. Using a sub-wire, short terminals T - E1 of "CHECK ENGINE" connector. See Figure.
  3. Read diagnostic code as indicated by number of flashes of "CHECK ENGINE" warning light. Diagnose codes by referring to the TCCS TROUBLE CODE IDENTIFICATION  table.
  4. The "CHECK ENGINE" warning light will blink a number of times equal to malfunction code indication with a 2.5 second delay between each indication. The diagnostic code series will be repeated as long as "CHECK ENGINE" connector terminals T - E1 are shorted.
    NOTE: In event of a number of trouble codes, indication will begin from the smaller value and continue to the larger in order.
    Fig 1: Example of Trouble Code Output
    G42853Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  5. If no trouble codes are stored in ECU memory, the "start code" will be displayed, followed by the "system normal" code. The "system normal" code consists of a series of needle fluctuations between 5 volts and 2.5 volts at 0.6 second intervals.
  6. Trouble codes are displayed in following manner: After the "start code", voltmeter needle will deflect a number of times between 2.5 volts and 5 volts at 0.6 second intervals. This is first digit of the trouble code.
  7. The needle will then indicate 2.5 volts for 2 seconds ("separator code"). Next, the needle will fluctuate between 2.5 volts and 0 volt at 0.6 second intervals. This is the second digit of the trouble code.
  8. Trouble codes will be displayed from lowest to highest numbered code. Output of the diagnostic codes will continue as long as the diagnostic mode is activated. A "separator code" follows display of first and second digit of trouble codes, and separates each trouble code. A "start code" will be displayed at the beginning of each pass through the output.
TCCS TROUBLE CODE IDENTIFICATION

Code No. (Pattern) Circuit Affected "CHECK ENGINE" Lamp
1 System normal OFF
2 Airflow meter signal ON
3 Ignition signal ON
4 Coolant temp. signal ON
5 Oxygen sensor signal ON
6 RPM signal ON
7 TPS signal OFF
8 Intake air temp. signal OFF
10 Starter signal OFF
11 A/C Switch or Neutral/Start Switch signal OFF
12 Knock sensor OFF
13 Knock CPU (ECU) ON