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Retrieving Codes

  1. Turn the ignition switch ON. Using SST (part number 09843-18020), connect terminals Tc and E1 of TDCL or check connector. See Fig 1 and Fig 2 .
    Fig 1: DLC Check Connector Terminals
    G91E03784Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    Fig 2: DLC 1 Check Connector Terminals
    G91H03785Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. Read the diagnostic code from the TRAC indicator light on the combination meter. Light will flash in sequence to indicate code digits. For example if only Code 21 is present, after a four second delay, the light will flash twice for a half second, go out for 1.5 seconds and flash four times for a half second each. If additional codes are present, they will flash after a 2.5 second pause. If codes are not present, the light will flash on and off in quarter second intervals.
    NOTE: If no code appears and trouble is suspected, inspect the diagnostic circuit. See TRAC INDICATOR LIGHT CIRCUIT under TROUBLE SHOOTING .
  3. Codes are explained in the DIAGNOSTIC CODE . After completing the check, disconnect terminals Tc and E1, and turn off the display. If two or more malfunctions are indicated at the same time, the lowest numbered diagnostic code will be displayed first.
DIAGNOSTIC CODE

Code Diagnosis
11 Open in TRAC brake main relay circuit
12 Short in TRAC brake main relay circuit
13 Open in TRAC throttle relay circuit
14 Short in TRAC throttle relay circuit
15 Electric supply to TRAC motor for a long time (Fluid leakage)
16 Open circuit in pressure switch circuit
17 Pressure switch remains OFF
19 TRAC motor ON and OFF operation is higher than a predetermined number of times (Accumulator pressure leakage)
21 Open or short in master cylinder cut solenoid valve circuit
22 Open or short in accumulator cut solenoid valve circuit
23 Open or short in reservoir cut solenoid valve circuit
24 Open or short in sub-throttle actuator circuit
25 Step motor does not move to a position decided by ECU
26 Sub-throttle valve does not move even when the sub-throttle valve is controlled to fully open position by ECU
27 When power supply to step motor is stopped, sub-throttle valve does not reach its fully-open position
44 During TRAC control, NE signals are not input to the ECU
45 When idle switch is ON, main throttle position sensor signal is 1.5V or higher
46 Main throttle position sensor signal is 4.3V or higher, or main throttle position sensor signal is 0.2V or lower when idle switch is OFF
47 When idle switch is ON, sub-throttle position sensor signal is 1.45V or higher
48 Sub-throttle position sensor signal is 4.3V or higher, or sub-throttle position sensor signal is 0.2V or lower when idle switch is OFF
49 Open or short in engine communication circuit
51 Problem in engine control system
52 Brake fluid level warning switch ON
54 Open in TRAC motor relay circuit
55 Short in TRAC motor relay circuit
56 TRAC pump motor locked
Always ON Malfunction in ECU

If a malfunction code is displayed during the diagnostic code check, check the circuit listed for that code.

AFFECTED CIRCUIT CODE

Code No. Circuit/Parts
11, 12 TRAC Brake Main Relay Circuit
13, 14 TRAC Throttle Relay Circuit
15 Fluid Leakage in Actuators or Tubing Pressure Switch Circuit
16, 17 Pressure Switch Circuit
19 Fluid Leakage in Actuators or Tubing Pressure Leakage of Accumulator
21, 22, 23 TRAC Actuator Solenoid Circuit
24 TRAC Sub-Throttle Actuator Circuit
25, 26, 27 TRAC Sub-Throttle Valve
44 NE Signal Circuit
45, 46 Main Throttle Position Sensor Circuit
47, 48 Sub-Throttle Position Sensor Circuit
49 Engine Communication Circuit
51 Engine Malfunction Detection Circuit
52 Brake Fluid Level Warning Switch Circuit
54, 55 TRAC Pump Motor Relay Circuit
56 TRAC Pump Motor Lock Sensor Circuit