Reverse lockout solenoid

Hi,

I´ve been trying to solve the problem with my reverse lockout solenoid, but I cannot find any explanation for the behaviour it has. So here it is how it works on my 94 RT/10:

- key off: I can select reverse gear feeling some spring tension
- key on: Same as above
- cruising over 5MPH: reverse can be selected without any spring tension, so I can misshift from 4th to R when trying to go for 5th.

I have understood that when cruising over 5MPH it is impossible (or nearly impossible, requiring a lot of force) to select reverse gear. But now I can do it very easily, so I suspect something is not working correctly..?

I took the solenoid assembly out of the car and I also cannot understand how it is able to lock the reverse just by examing this part in my hands? Because without power/ground connection the sping/piston assembly is sticking out of the housing slightly and when I cruise over 5MPH the small pin inside retracts and the spring/piston assy is able to slide inside the housing almost completely...and I suspect this causes the shifter to be able to be used to select reverse without any spring tension, just like from 1-2 row to 3-4, for example.

And the reverse lock has been working on my car previously, but some time ago it didn´t prevent the reverse gear selection at over 5MPH anymore.

Can anyone expain how this system is mechanicly able to lockout reverse gear selection and how the solenoid should work? (when the pin inside should retard, etc...)

Thank you for your replies and thoughts about this & best greetings from Finland.

Have you tried some simple steps likes ohming the coil on the solenoid or checking the cable to it for voltage?

Hello.

I measured the resistance from the solenoid pins and I got 13ohms... But I don´t know what to do with this information.

Do you people have any other suggestions regarding this problem?

Sounds like the coil has continuity. Did you try seeing if the coil gets power to it via the wires? You'd have to have the car on stands with the speedo at 5 or 10 mph whatever that magic lockout speed is.

Mika,

Here is the T-56 manual: http://www.ttcautomotive.com/English/media/pdfs_autogen/T-56_Service_Manual.pdf

See section 3-12-2 for solenoid diagnostic information.

When the reverse lockout is grounded, you can engage R. When it isn't (as in when the car is off), you can't. I've actually had a case of needing to manually wire the ground due to the exact opposite problem: NOT being able to engage reverse. I'd check the harness and clean it out. Sometimes a little contact cleaner and/or dialectic grease does the trick.

good luck!