Toyota RAV4 manuals

Toyota Sienna Service Manual: Check and replace ecu

NOTICE: • The connector should not be disconnected from the ECU. Perform the inspection from the backside of the connector on the wire harness side.

• When no measuring condition is specified, perform the inspection with the engine stopped and the ignition switch on.

• Check that the connectors are fully seated. Check for loose, corroded or broken wires.

(a) First, check the ECU ground circuit. If it is faulty, repair it. If it is normal, the ECU could be faulty.

Temporarily replace the ECU with a normally functioning one and check if the symptoms occur. If the trouble symptoms disappear, replace the original ECU.

Measure the resistance between the ECU ground terminal and body ground

(1) Measure the resistance between the ECU ground terminal and body ground.

Standard resistance: Below 1 Ω

Disconnect the ECU connector

(2) Disconnect the ECU connector. Check the ground terminal on the ECU side and wire harness side for bending, corrosion or foreign matter. Lastly, check the contact pressure of the female terminals.

Check for short circuit
(a) If the wire harness is ground shorted (Fig. 5), locate the section by conducting a resistance check with the body ground (below).   (b) Check the resistance with the body ground. ...

How to proceed with troubleshooting
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Other materials:

Inspection
1. INSPECT INVERTER MAIN SWITCH  Inspect the continuity between terminal at the each switch position shown in the chart. If continuity is not as specified, replace the main switch assembly.  Inspect the bulb state when connecting the battery to each terminal ...

Using a Bluetooth® Phone
The hands-free system is a function that allows you to use your cellular phone without touching it. This system supports Bluetooth®. Bluetooth® is a wireless data system that allows the cellular phone to wirelessly connect to the hands-free system and make/receive calls. Before making a p ...

Write vin
(a) The VIN writing process is shown in the flowchart below. This process allows the VIN to be input into the ECM. If the ECM is changed, or the ECM VIN and Vehicle VIN do not match, the VIN can be registered, or overwritten in the ECM by following this procedure. (b) Write VIN using the int ...

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