Toyota Sienna Service Manual: Electronic circuit inspection procedure

General information

A large number of ECU controlled systems are used in the SIENNA. In general, ECU controlled systems are considered to be very intricate, requiring a high level of technical knowledge to troubleshoo ...

Basic inspection

(a) WHEN MEASURING RESISTANCE OF ELECTRONIC PARTS (1) Unless otherwise stated, all resistance measurements should be made at an ambient temperature of 20°C (68°F). Resistance measurements may b ...

Other materials:

Terminals of ECU
1. CHECK DRIVER SIDE J/B ASSEMBLY (MULTIPLEX NETWORK BODY ECU)  Disconnect the B6, 1C, 1K and 1L J/B connectors. Measure the voltage and resistance according to the value(s) in the table below. HINT: If the result is not as specified, there may be a malfunction on the w ...

Road test
1. PROBLEM SYMPTOM CONFIRMATION  Inspect the SET function.  Turn the cruise control main switch on.  Drive at the required speed between 40 km/h (25 mph) and 200 km/h (125 mph).  Push the cruise control main switch to - (COAST)/SET.  After releasing t ...

On-vehicle inspection
1. INSPECT SPEEDOMETER  Check the operation.  Using a speedometer tester, check the speedometer indication according to the table below. Reference: mph (U.S.A.) Reference: km/h (Canada) NOTICE: Tire wear as well as over or under inflation will cause errors. ...