Toyota Sienna Service Manual: Check for intermittent problems
1. CHECK FOR INTERMITTENT PROBLEMS
HINT:
For use of the intelligent tester only: Inspect the vehicle's ECM using check mode.
Intermittent problems are easier to detect with an intelligent tester when the ECM is in check mode. In check mode, the ECM uses 1 trip detection logic, which is more sensitive to malfunctions than normal mode (default), which uses 2 trip detection logic.
(a) Clear the DTCs (See page ES-39).
(b) Switch the ECM from normal mode to check mode using an intelligent tester (See page ES-43).
(c) Perform a simulation test (See page IN-35).
(d) Check and wiggle the harness(es), connector(s) and terminal(s) (See page IN-30).
How to proceed with
troubleshooting
HINT:
The intelligent tester can be used in steps 2, 3, 4, 6 and 9.
1 VEHICLE BROUGHT TO WORKSHOP
2 CONNECT INTELLIGENT TESTER TO DLC3
HINT:
If the display indicates a communication fault in th ...
Basic inspection
When a malfunction is not confirmed by the DTC check,
troubleshooting should be carried out in all circuits
considered to be possible causes of the problem. In many
cases, by carrying out the basic ...
Other materials:
Precaution
1. TIRE PRESSURE WARNING SYSTEM PRECAUTION
(a) When the tire pressure warning light comes on,
immediately check the tire pressure of the tire and
adjust it to the specified value. (The tire pressure
warning light will come on after blinking for 1 minute
if there is an open in the tire press ...
Light Sensor Circuit Malfunction
DTC B1244 Light Sensor Circuit Malfunction
DESCRIPTION
This DTC is output when failure in the light sensor circuit is detected.
DTC No.
DTC Detection Condition
Trouble Area
B1244
Malfunction of automatic light control sensor
Open or short of a ...
Approach warning
When your vehicle is too close to a vehicle ahead, and sufficient automatic
deceleration via the cruise control is not possible, the display
will flash and the buzzer will sound to alert the driver. An example of
this would be if another driver cuts in front of you while you are following
a vehi ...
