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:

Multiplex Communication Circuit
DESCRIPTION INSPECTION PROCEDURE 1 GO TO CAN COMMUNICATION SYSTEM (a) Refer to the CAN communication system (See page CA- 7). (b) If the CAN communication system is operating normally, proceed to the next step. 2 GO TO MULTIPLEX COMMUNICATION SYSTEM (BEAN) (a) Refer to the multiplex com ...

Short to GND in Front Pretensioner Squib RH Circuit
DTC B0132/61 Short to GND in Front Pretensioner Squib RH Circuit DESCRIPTION The front pretensioner squib RH circuit consists of the center airbag sensor assembly and the front seat outer belt assembly RH. This circuit instructs the SRS to deploy when deployment conditions are met. DTC B ...

Cooling system
On-vehicle inspection 1. INSPECT FOR COOLANT LEAK CAUTION: Do not remove the radiator cap while the engine and radiator are still hot. Pressurized, hot engine coolant and steam may be released and cause serious burns. NOTICE: Before performing each inspection, turn the A/ ...