Reading Diagnostic Trouble Codes

To obtain an output of the diagnostic codes, proceed as follows:
1. The following initial conditions must be established:
a. Battery voltage above 11 volts.
b. Throttle valve completely closed.
c. Transmission in Neutral position.
d. Accessory switches off.
2. Turn ignition switch to ON position. Do not start engine.
3. Short terminals T and E1 on 3S-GTE, 3VZ-E and 4A-GZE engines or TE1 and E1 on 2VZ-FE engines.
4. Read diagnostic codes as indicated by the number of flashes of the check engine warning lamp.
5. During normal system operation, the check engine lamp will blink as follows:
a. On 2VZ-FE engines, the check engine lamp will alternately blink on and off at .26 second intervals.
b. On 3S-GTE engines, the check engine lamp will alternately blink on and off at .25 second intervals.
c. On 3VZ-E engines, the check engine lamp will blink once every .25 seconds.
d. On 4A-GZE engines, the check engine lamp will blink once every .5 seconds.
6. A malfunction code indication will be as follows:
a. On 3VZ-E and 4A-GZE engines, the check engine lamp will blink a number of times equal to the malfunction code indication. Between the first digit and second digit, 1.5 seconds. Between code and code, 2.5 seconds. Between all malfunction codes 4.5 seconds. The diagnostic code series will be repeated as long as the check connector terminals T and E1 are shorted. In the event of a number of trouble codes, indication will begin from the small value (numerically) and continue to the larger number code in order. After diagnosis is completed, remove jumper wire from check connector.
b. On 2VZ-FE and 3S-GTE engines, the check engine lamp will blink every .5 seconds. The first number of blinks will equal the first digit of a two digit diagnostic code and after a 1.5 second pause, the second number of blinks will equal the second diagnostic code. If there are two or more codes, there will be a 2.5 second pause between each. After all the codes have been signalled, there will be a 4.5 second pause and they will all be repeated as long as check connector terminals T and E1 on 3S-GTE engine or TE1 and E1 on 2VZ-FE engine are shorted. In the event of a number of trouble codes, indication will begin from the smaller value and continue in order to the larger. After diagnosis is completed, remove jumper wire from check connector terminals.