Toyota Sienna Service Manual: Customer problem analysis

Toyota Sienna Service Manual / Introduction / How to troubleshoot ecu controlled systems / How to proceed with troubleshooting / Customer problem analysis

HINT:

In troubleshooting, confirm that the problem symptoms have been accurately identified. Preconceptions should be discarded in order to make an accurate judgment. To clearly understand what the problem symptoms are, it is extremely important to ask the customer about the problem and the conditions at the time the malfunction occurred.
Gather as much information as possible for reference.
Past problems that seem unrelated may also help in some cases.
The following 5 items are important points in the problem analysis:

What	Vehicle model, system name
When	Date, time, occurrence frequency
Where	Road conditions
Under what conditions?	Running conditions, driving conditions, weather conditions
How did it happen?	Problem symptoms

Operation flow

HINT: Perform troubleshooting in accordance with the procedures below. The following is an outline of basic troubleshooting procedures. Confirm the troubleshooting procedures for the circuit you a ...

Symptom confirmation and diagnostic trouble code

HINT: The diagnostic system in the SIENNA has various functions. The first function is the Diagnostic Trouble Code (DTC) check. A DTC is a code stored in the ECU memory whenever a malfunctio ...

Other materials:

System description
1. BRIEF DESCRIPTION The CAN (Controller Area Network) is a serial data communication system for real time application. It is a vehicle multiplex communication system which has a high communication speed (500 kbps) and the ability to detect malfunctions. By pairing the CANH and CANL bu ...

On-vehicle inspection
1. INSPECT REAR AXLE HUB BEARING BACKLASH (a) Using a dial gauge, check for backlash near the center of the axle hub. Maximum: 0.05 mm (0.0020 in.) If backlash exceeds the maximum, replace the axle hub assembly. NOTICE: Ensure that the dial gauge is set at right angles to the measuremen ...

Sensor detection display, obstacle distance
Distance display Sensors that detect an obstacle will illuminate continuously or blink. *1: The images may differ from that shown in the illustrations. *2: Multi-information display *3: Audio system screen Buzzer operation and distance to an obstacle A buzzer sounds when the sensors are o ...