09 Daihatsu Terios. A/T U540E no reverse

Hi everyone,

Do you guys have any experience of reading these solenoids (pintle working) with a scope?

At this point i know one of the hydraulic circuits is delaying 4 seconds to engage its brake (B2).

I completely teared down and cleaned the valve body (same thing after assembly)

Knowing that solenoid is activating on schedule, how do i know if pintle is activating correctly?

Thanks in advance.

The pintle opening can be seen in the current waveform. RED Trace.
The pintle closing can be seen in the voltage waveform. Blue trace.

Hi pole71,

Oh really? Same as injectors?

Thank you so much.

The voltage and current pintle hump method definitely works on transmission solenoids.

The only problem is getting the waveform you want, as some solenoids are PWM controlled. To get a clear waveform, you usually have to control the power/ground yourself (as in, jumper wires).

If you're concerned about delayed engagement, then you might be fighting a pressure leak in the B2 circuit somewhere else in the transmission. Might be useful to watch line pressure while shifting into reverse and see what the pressure does.

Yes, you are right.

This one is pwm controlled (kind of hard to know how pintle is moving since pintle movement is continous)

About pressure. The gauge showed pressure 4 seconds after you selected "R". I can see that hydraulic delay, but i like to see where exactly leakage is, since history of this transmission tells me that leakage could be in oil pump, valve body, pistons or drains (i mean everywhere). That could be also an actuator still sticking.

Is just a bet to replace the valve body.

Sounds like some kind of leak, then. Does SI for this transmission point out any pressure test points with the valve body out?

It used to be that OEs would point out which port did what in the trans, so you could put air pressure to various bands/actuators/whatever and listen for air leaks.

I'm not familiar with this transmission? Just an idea for testing if you're gonna pull the valve body off again.