Introduction

All A340 series automatic transmissions are 4-speed electronic controlled transmissions. Solenoids that control shifts are located in valve body. Transmission consists of lock-up type torque converter clutch, OD direct clutch, direct clutch, forward clutch, 2nd brake, 2nd coast brake, OD brake, overdrive planetary gear units, planetary gear unit, hydraulic control system and electronic control system. See Fig. 2.

Solenoids are controlled by an Engine Control Module (ECM). For electronic diagnosis, see appropriate DIAGNOSIS article. ECM receives information from various input devices and uses this information to control solenoids for transmission shifting and lock-up solenoid for torque converter clutch TCC lock-up.

An Overdrive (OD) switch is mounted on selector lever. When OD switch is depressed to ON position, transmission will shift into 4th gear when selector lever is in "D" position, and OD OFF light on instrument panel will go off. When OD switch is released to OFF position, transmission will shift into 3rd gear, and OD OFF light on instrument panel will illuminate.

Some models are equipped with a pattern select switch which is located near selector lever on center console. Pattern select switch contains a POWER (PWR) and a NORMAL (NORM) operating position. When pattern select switch is depressed (PWR position), transmission upshifts and downshifts will occur at a higher vehicle speed than with switch released. An indicator light on instrument panel indicates pattern select switch is in PWR (on) position. On some models, pattern select switch may include a 2nd start switch. Transmission starts out in 2nd gear when 2nd start switch is activated.

A340F transmission has a mechanically controlled 2-speed 4WD transfer case. Transfer case consists of planetary gears, hydraulic clutches and hydraulic brake. Transfer case is mounted to rear of transmission case.

Transmission is equipped with a shift lock and key lock system. Shift lock system prevents selector lever from being moved from Park unless brake pedal is depressed. Key lock system prevents ignition key from being moved from ACC to LOCK position on ignition switch unless selector lever is in Park. For more information on shift lock and key lock system, see appropriate SHIFT INTERLOCK SYSTEMS article.

A330 Electronics Chart

2001-05 AUTOMATIC TRANSMISSIONS A340E & A340F Overhaul

Fig. 2: Identifying Transmission Component Locations Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Was this article helpful?

0 0
Simple Car Care Tips and Advice

Simple Car Care Tips and Advice

Put an End to All Your Car Troubles. Does Your Car Break Down Often? Are You Spending More On Fuel Than You Thought You Would? Is Maintaining Your Car Eating Into Your Budget? Make Your Car Last Longer with Some Simple Do It Yourself Tips.

Get My Free Ebook


Post a comment