Toyota U140/U240 Series Diagnostic Information

Thistransmissionhas some unique problems that can cause you to scratch your head. Add the lack of information available from the manufacturer and your frustration level can skyrocket. Here are some common problems and suggestions on how to resolve them.

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Binding On the 1-2 Shift:

Binding on the 1-2 shift is a common complaint with this transmission. A quick way to determine if you have a valve body/solenoid problem or a faulty ECM is to see if you have reverse with the electrical connector disconnected from the transmission. If you do NOT have reverse, suspect the B2 control valve stuck on or pushed to the apply position by cross leaks or a DSL solenoid stuck open. If the transmission engages into reverse, suspect a faulty ECM.

Here's why. The DSL solenoid, also known as the TCC solenoid, doesn't just come on for lock up. The DSL solenoid is also energized in manual low and is used to inhibit reverse. The DSL solenoid is a normally closed solenoid. When energized, it allows oil pressure to stroke the B2 control valve, apply the B2 clutch in manual low, and block oil to the B2 clutch in reverse. If the DSL solenoid is stuck open in drive, the B2 clutch will apply in 1st as it does in manual low. When the 1-2 shift occurs with the B2 clutch applied, one too many clutches are applied and the transmission binds up. If the DSL solenoid is stuck open when reverse is selected, the B2 control valve will block oil to the B2 clutch, inhibiting reverse.

The engine and the transmission are controlled by the ECM (Engine Control Module), more commonly known as the PCM (Powertrain Control Module) in these units. It is not uncommon for 2001 – 2003 RAV4 vehicles to have a faulty ECM. Many times the vehicle will have binding or harsh shifts, which are often be accompanied by codes P0750, P0753, P0755, P0758, and P1760. For more information, see Toyota bulletin # TC002-06 with an issue date of March 3, 2006.

在您订购新ECM之前，请注意以下内容。请记住，使用自适应策略来控制该传输，并且必须重置学习的适应，以避免在传输大修或阀体更换后损坏传输。请记住，重置过程将重置所有ECM所学习的ADAPTS，而不仅仅是传输适应。丰田工厂扫描仪能够重置ECM ADAPTS。重置ADAPTS应后续进行重新学习过程。将横向划线带到工作温度。接下来，通过所有换档驱动车辆在光线稳定节流阀中，然后重复直到换档感觉正常。您可能会发现重置移位适应将纠正班次上的任何绑定，而无需更换ECM。在更换ECM之前，我强烈建议首先执行ECM重置。

Gear	SL1.	SL2	SL4.	* DSL / TCC
1st	在	在	Off
2nd	Off	在	Off
3rd	Off	Off	Off
3rd TCC on	Off	Off	Off	在
4th	Off	Off	在
4th TCC on	Off	Off	在	在
Manual 1st	在	在	Off	在

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2-3滑动，火炬/延迟或没有反向：

The direct clutch sealing rings wear into the ring grooves in the cover and the direct drum is frequently ring grooved. Proper clearance between the sealing ring and the ring land is .003" to .005". Direct drums with damage where the sealing rings ride should be replaced. Do NOT try to salvage the drum by sanding out the damage.

Another cause of pressure loss to the direct clutch is a missing or incorrectly positioned rubber washer type seal between the case and the rear cover.

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反向滑动或没有反向：

In addition to the direct clutch problems, a DSL solenoid that is stuck "on," a B2 control valve that is stuck in the stroked position, or missing or damaged B2 seals between the valve body and case can cause reverse to be delayed, slip or be missing altogether.

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Various Shift and Engagement Feel Concerns:

Various shift and engagement feel concerns can be due to accumulator spring mix up. The chart below shows the location, color and dimensions of each accumulator spring in the case.

• C1蓄能器用于中性以驱动接合感。
• The C3 accumulator is for the 3-4 shift feel.
• B3累加器将影响4-3次降档感受。

Bore	Spring Location	Color	Free Length	Dia.	线圈数量＃	Wire Dia.
C1	案例侧	Red	3.555"	.727“	14.5	.075"
C3 Outer	vb侧	白色的	3.645”	.738"	14	.117"
C3内部	vb侧	Plain	.470"	.450“	3	.078“
B3外面	案例侧	Blue	2.945“	.856"	10	.098"
B3 Inner	案例侧	绿色的	2.370"	.625“	12	.085"

一如既往，信息是第一次修复它的关键。

杰夫帕里尔is Director of Product Support at Valve Body Xpress and a member of the SonnaxTASC Force®(Technical Automotive Specialties Committee), a group of recognized industry technical specialists, transmission rebuilders and Sonnax Industries Inc. technicians.