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:

Power Source Circuit
DESCRIPTION Power is supplied to the fold seat control ECU through the L-RR2 SEAT and R-RR2 SEAT fuses. WIRING DIAGRAM INSPECTION PROCEDURE 1 INSPECT FUSE (L-RR2 SEAT, R-RR2 SEAT) Remove the fuses from the R/B No. 3.  Measure the resistance according to the value(s) in the ...

Diagnosis system
1. CHECK DLC3 (a) The vehicle's ECM uses the ISO 15765-4 for communication. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 15765-4 format. HINT: Connect the cable of the intelligent tester to the DLC3, turn the ignition switch to the ON position and atte ...

Installation
HINT: Install the RH side by the same procedure as the LH side. 1. INSTALL REAR DISC BRAKE CYLINDER MOUNTING LH (a) Install the rear disc brake cylinder mounting LH with the 2 bolts. Torque: 88 N*m (900 kgf*cm, 65 ft.*lbf) 2. INSTALL REAR DISC BRAKE PAD SUPPORT PLATE (a) Install the rear d ...

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