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Normal Mode

  1. Normal Mode is used for routine testing of vehicle. To read diagnostic codes, ensure battery voltage is at least 11 volts, throttle valve is fully closed, transmission is in Neutral and all accessories are off.
  2. The Total Diagnostic Communication Link (TDCL) connector is located under left side of instrument panel. See Fig 1. Diagnostic codes can be obtained through TDCL connector or check connector. Check connector is located in engine compartment near left shock tower. See Fig 2.
  3. Turn ignition on. DO NOT start engine. Using a jumper, wire connect terminals E1 and TE1 together either on TDCL connector or check connector. See Fig 3. Count number of flashes from CHECK engine light.
  4. If CHECK engine light flashes 2 times every second, this indicates system is normal. If a diagnostic code is displayed, first group of flashes will provide first digit of a 2-digit diagnostic code. There will be a 1.5 second delay between first digit and second digit of diagnostic code. The second group of flashes will equal second digit of diagnostic code.
  5. If more than one code is stored, there will be a 2.5 second delay between diagnostic codes. After all diagnostic codes have been displayed, a 4.5 second delay will occur, then diagnostic codes will be repeated until jumper wire connecting terminals E1 and TE1 is disconnected. Diagnostic codes will display from smallest to largest number.
  6. Record diagnostic codes. See DIAGNOSTIC CODE IDENTIFICATION  table for description of possible circuit problem. After reading diagnostic code description, see appropriate diagnostic code chart. To clear codes, see CLEARING CODES in this article.
Fig 1: Locating TDCL Connector
G90H18884Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 2: Locating Check Connector (ES250)
G90I18885Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
NOTE: Test Mode is not available on ES250.
Fig 3: Identifying TDCL & Check Connector Terminals
G90A18887Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
DIAGNOSTIC CODE IDENTIFICATION (1)

Code (2) CHECK Engine Light Signal Affected
12  On RPM
13  On RPM
14  On Ignition
16  On (3) ECT Control
21  On Main Oxygen Sensor Or Sensor Heater
22  On Water Temperature Sensor
24  On (Calif. Only) Intake Air Temperature Sensor
25  On Air/Fuel Ratio Lean Malfunction
26  On Air/Fuel Ratio Rich Malfunction
27  On Sub-Oxygen Sensor (California Only)
31  On Airflow Meter
32  On Airflow Meter
41 (4) On (Calif. Only) Throttle Position Sensor
42  Off Vehicle Speed Sensor
43 (5) Off Starter
51  Off Switch Condition
52  On Knock Sensor
53  On Knock Control
71 (4) On EGR System Malfunction (California Only)
(1) If diagnostic code displayed is not shown in this table, ECU is faulty.
(2) All diagnostic codes except Codes 16, 51 and 53 will remain in ECU memory until erased.
(3) Electronically Controlled Transmission (ECT).
(4) California vehicles only.
(5) Code 43 sets if vehicle is push started.