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Retrieving Diagnostic Trouble Codes

  1. Turn ignition switch to ON position. Ensure TRAC OFF (except GS300) or TRAC (GS300) indicator light illuminates for 3 seconds and turns off. If TRAC OFF (except GS300) or TRAC (GS300) indicator light does not function as indicated see TRAC OFF INDICATOR, TRAC CUT SWITCH CIRCUIT test.
  2. On all models except GS300, ensure ignition switch is in ON position. If a DTC is set, after TRAC OFF indicator light has illuminated for 3 seconds, it will begin blinking every 1.5 seconds. If DTC 53 is set TRAC OFF indicator may remain on (without blinking) until engine is started.
  3. On all vehicles, ensure ignition switch is in ON position. Using a fused jumper wire or service connector (SST 09843-18020), connect terminals Tc and E1 of Data Link Connector No. 1 (DLC1) or Data Link Connector No. 2 (DLC2). See Fig 1. DLC1 is located in engine compartment, left front side of plenum chamber, across from strut tower. DLC2 is located under left side of instrument panel (GS300) or right side of instrument panel (SC300 and SC400), near kick panel. On LS400 DLC2 is located under center of instrument panel.
  4. On all models, turn ignition on. If a malfunction is detected, TRAC OFF indicator light will begin to flash a 2-digit DTC after 4 seconds. TRAC OFF indicator light will flash first digit, followed by a 1.5-second pause and then second digit.
  5. Count number of flashes to obtain digits of 2-digit code. If 2 or more codes are stored, a 2.5-second pause will separate codes. If 2 or more malfunctions are indicated at the same time lowest numbered DTC will be displayed first. See DIAGNOSTIC TROUBLE CODE IDENTIFICATION table for code diagnosis SELF-DIAGNOSTICS.
  6. If ABS is functioning properly a normal code will be set. During normal code, 2 seconds will elapse, and then TRAC OFF indicator light will blink once every .25 second.
  7. If TRAC OFF (except GS300) or TRAC (GS300) indicator light does not illuminate, see Tc TERMINAL CIRCUIT or TRAC INDICATOR LIGHT CIRCUIT tests. After replacing or repairing malfunctioning components, clear diagnostic trouble codes, see CLEARING DIAGNOSTIC TROUBLE CODES (DTCS) . Turn ignition off. Remove fused jumper wire or service connector (SST 09843-18020), from DLC1 or DLC2 connector.
Fig 1: DLC2 Connector & DLC1 Check Connector Terminals
G94G47692Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
IDENTIFYING DIAGNOSTIC TROUBLE CODES (1997)

DTC Condition
24  Sub-Throttle Actuator Open Or Short Circuit
25  Step Motor Does Not Move To A ECU Decided Position
26  Sub-Throttle Valve Does Not Move Even When Sub-Throttle Is Controlled To Fully Open Position By ECU
28 (1) Throttle Valve Motor Driver Malfunction
29 (1) Malfunction In Throttle Valve Motor Driver
31 (2) Right Front Wheel Speed Sensor Signal Malfunction
32 (2) Left Front Wheel Speed Sensor Signal Malfunction
33 (2) Right Rear Wheel Speed Sensor Signal Malfunction
34 (2) Left Rear Wheel Speed Sensor Signal Malfunction
41 (2) Low Or High Battery Voltage
43  ABS Control System Malfunction (Except GS300)
43 (3) ABS Or TRAC (BRAKE) Control System Malfunction (GS300)
44  Open Or Short In NE Signal Circuit
45 (2) Main Throttle Position Sensor Circuit Malfunction
46 (2)(4) Main Throttle Position Sensor Signal Malfunction
47  Sub-Throttle Position Sensor Circuit Malfunction
48  Open Or Short In Sub-Throttle Position Sensor Circuit
49 (2) Open Or Short In Engine Communication Circuit
51 (5) ECM System Malfunction (Except GS300)
51 (6) Engine & ECT System Malfunction (GS300)
52  Low Brake Fluid Level (Except GS300)
53  ECM Communication Circuit Malfunction (Except GS300)
61  ABS/TRAC ECU & TRAC ECU Communication Circuit Malfunction
Always On (6) ABS/TRAC ECU & TRAC ECU Malfunction (Except GS300)
Always On Malfunction In TRAC ECU & TRAC Indicator Light (GS300)
(1) On LS400, and 1997 SC300 and SC400.
(2) On GS300.
(3) On GS300, TRAC OFF indicator light or TRAC indicator light will illuminate if malfunction is detected by ECU.
(4) On GS300, TRAC indicator light will no illuminate if malfunction is detected by ECU.
(5) When malfunction is no longer detected, DTC will erase automatically.
(6) TRAC OFF indicator light will illuminate if malfunction is detected by ECU
IDENTIFYING DIAGNOSTIC TROUBLE CODES (1998)

DTC Condition
43  ABS Control System Malfunction
44  Open Or Short In NE Signal Circuit
51 (1) ECM System Malfunction
52 (1) Low Brake Fluid Level, Open In Brake Fluid Level Warning Switch Circuit
53  ECM Communication Circuit Malfunction
Always On (2) ABS/TRAC ECU & TRAC ECU Malfunction
(1) When malfunction is no longer detected, DTC will erase automatically.
(2) TRAC OFF indicator light will illuminate if malfunction is detected by ECU