1. DTC CHECK (SENSOR CHECK)

(a) After the indicator check is completed, the system enters the DTC check mode automatically.
(b) Read the codes displayed on the panel. Refer to the list of codes (See page AC-19) when reading the codes. (Trouble codes are output at the temperature display.)

(c) If the slower display is desired, press the DEF switch and change it to the step operation. Each time the DEF switch is pressed, the display changes by 1 step.
2. CLEARING DTC

(a) To clear diagnostic trouble codes, there are 2 ways.
(1) During sensor check, press the "DEF" switch and "A/C" switch at the same time.
(2) Remove the ECU-B fuse in the engine room junction block for 20 seconds or longer to clear the DTC memory.
Diagnosis system
Check mode procedureRemoval
1. REMOVE V-BANK COVER SUB-ASSEMBLY (See
page EM-28)
2. REMOVE NO. 1 ENGINE UNDER COVER (See page
EM-26)
3. DRAIN ENGINE COOLANT (See page CO-6)
4. REMOVE NO. 2 AIR CLEANER INLET (See page EM-
28)
5. REMOVE BATTERY (See page EM-26)
6. REMOVE FRONT BUMPER ASSEMBLY (See page
ET-3)
7. REMOVE ...
When servicing full-time 4wd vehicles
The full-time 4WD SIENNA is equipped with the open
center differential system.
If incorrect preparations or test procedures are used, the
test will not only be unsuccessful, but may be dangerous
as well.
Therefore, before beginning any such servicing or test,
be sure to check the following ...
Inspection
1. INSPECT FRONT SPEED SENSOR
(a) Make sure that there is no looseness at the
connector lock part and connecting part of the
connector.
(b) Disconnect the speed sensor connector.
(c) Measure the resistance between terminals 1 and 2
of the speed sensor connector.
OK:
Resistance:
0.92 ...