Where is the reverse light switch?

[cbose]

The car is a 91 Legacy 2.0L stationwagon with 5MT. Japan model. There are two
switches on the left side of the transmission. I assume one is a neutral
sensor and the other is the reverse light switch. Which one, the front
one or the rear one?

My reverse lights stopped working about a month ago and it is
time tor the semiannual warrant of fitness down here in NZ. I need
the lights to work.

Both switches seem to be screw-in plugs with no adjustments.
Any hope that the switch can be fixed or am I looking at another
trip to the dealer

Chris

[vrg3]

I assume one is a neutral sensor and the other is the reverse light switch. Which one, the front one or the rear one?

You're right; the front one is the reverse switch and the rear one is the neutral switch.

I don't know how the switches work exactly so I don't know if you can repair them, but it can't hurt to unscrew the switch and examine it. Maybe you can clean it out with brake cleaner if it's sticking or if the contacts are dirty.

[cbose]

Thanks for the pointer to the front switch. It is easy to get out.

It consists of a plastic actuator rod passing into a sealed metal
switch body which is in turn screwed into the transmission case.
The plastic rod is pressed by internal metal parts inside
the transmission when reverse is selected. In my case, the plastic actuator
contact surface had worn down so much the switch was no longer closing.
However, if the switch body can be installed 180 degrees from its
original position, contact will be made at a fresh surface on
the actuator rod and the original throw of the switch will be restored.

This is what I did. It is made easy because the switch body is sealed at
the trans case with an aluminum washer. By slightly shaving this
washer (with a file and course sandpaper) you can arrange the
switch body to torque down a little bit further around.

Suggestion: Mark the position of the switch body before you
remove it the first time. That way, you can easily see if it is seating
180 degrees further around. If not, shave a little more off the washer.
I didn't anticipate the fix and so had to fiddle a bit to get the position
right.

The switch lasted in its original position for 200,000km. It might
outlast the car now having been rotated once.

Chris

[vrg3]

Wow, nice! That's good info to know.

Did you use some kind of threadlocker to make sure it wouldn't back itself out, since it's no longer fully tightened?

[cbose]

No, there is no need for threadlocker. The aluminum washer is about
2mm thick and the thread pitch on the switch body is about 1mm, so if
you take around 1/4 of the thickness of the washer off with a file and
sandpaper, you get about 1/2 turn more before the switch torques
down. It takes about 2 minutes to do the washer and you get a nice
flat, slightly rough sealing surface in the bargain. Just be sure not to get
the washer too much tapered, that is, the two flat faces should be pretty
parallel. I've done this many, many times in other applications for restoring
hard to find sealing washers (old mercedes in particular, that use lots
of copper washers) and never had a problem. If you want to be really
picky (and I usually am) hold the sandpaper on something really flat, like
a piece of glass or a machined cast iron surface (table saw?) and rub the washer
back and forth with the end of your finger. Does wonders for cleaning up
the old grease stains in the fingerprint lines on the end of your finger:)

Of course, this trick doesn't work on the 'rolled' crush washers like the
type used on the oil pan drain plug -- they're a one-time throwaway item.

Chris

[vrg3]

Ah, cool, very nice! Thanks for the how-to for all the rest of us.

[DeusExMachina]

Sorry to dig up an old thread, but I went to change my gear oil and fix a leak at my reverse switch today. I couldn't figure out how to disconnect the harness at first (go me) so I tried turning it, hoping the thread wasn't very long. No such luck, and I must've bent one of the wires too much, when I went to re-install with a new washer gasket, a wire snapped off. 26 bucks later and waiting till Wednesday, I'll have a new switch.

I wanted to ask this question, though: Do I need to drain the gear oil before replacing the switch? I just put in some hard-to-find Castrol 75W90 Hypoy C and I'd rather not waste it.

[THAWA]

I think you mgith have to, it's one of those switches that's lwoer than the full level. you could try angleing the transmsioon so it is above the level of the fluid.

[DeusExMachina]

Probably more trouble than its worth. The tranny will just be babied, having the fluid changed twice in 100 miles. Maybe i wont like the Castrol stuff, but that'll create more problems.

[J-MoNeY]

Does anyone have a pic of this switch or a discription of where it is when looking in the engine bay from the front of the car?

[vrg3]

You can't see it from the engine bay. It's fairly easy to access from underneath the car though. This diagram shows about where it is:

http://www.graphics.cornell.edu/~v/pics ... itches.png

[Legacy777]

you see the black & white connectors in this pic?
http://www.surrealmirage.com/subaru/ima ... P_3267.JPG

Follow the wires to the things plugged into the tranny. The front one is the reverse switch, the back one is the neutral switch.

[gijonas]

Just wanted to update this thread with info i dicovered today.My reverse lights stopped working and narrowed it down to the switch on the tranny.Well i got looking at one on an old loyale trans laying behind my shop and voila!!! same same .This leads me to believe any manual suby trans uses the same thing,even has the same connector!! love the plug and play stuff.