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kronopoliz
08/20/2008, 06:05 PM
:_wrench:If you are experiencing issues with faulty shift indicator on your instrument cluster it is most likely your mode selector switch. This may be indicated by shifting to drive but displays neutral, reverse showing while in neutral, flickering or jumping, or no light at all. Because the transmission is electronically controlled this condition may also come with erratic and violent up and down shifting due to negative feedback through the TCU. This condition is often intermittent. A replacement part can go for upwards of $250 and many of you have indicated that the replacement part may not work either. Their is a simple fix. Took me 30 minutes and I'm no mechanic.

1.) Locate the mode selector switch on the driver side underneath the vehicle attached to the transmission. You should barely see the green serial number tag on the transmission body above it. You will also see a wire cluster connecting to the part from the rear of the vehicle to this part. This part is roughly the size of your palm.

2.) Once located pop off the dust cover with a screwdriver which is connected with spring steel in three points. Releasing the bottom and forward will allow removal without having to get to the difficult top point. Then remove the 14mm bolt attaching shift linkage to switch and pull away.

3.) The part is attached with two 10m bolts. One on forward and one on top slightly recessed from the body of the switch. You can get to this with a 2 inch extension and socket wrench, a little patience, and a flexible wrist.
* Make sure the vehicle has cooled down as you will touch the exhaust pipe and transmission body.

4.) The unit will come loose from the transmission, however is still attached via cable cluster. About six inches up the wire is a molex connection. This plug is attached to a metal plate and I had to break the plastic attachment to loose it so you'll have to figure that one out! You'll also have to clip some wire ties as well. The plug can now be separated by popping loose one plastic pressure tab and carefully pulling.

5.) With the unit in hand remove the cover screws with a torque bit t-15.

6.) Pay attention to the red gasket seal as it easily expands or contracts with temperature differences making it impossible to fit upon assembly. Pressurized carb cleaner caused mine to expand causing me to cut it down to fit. I'm sure this will shrink with heat causing a gap in the seal possibly exposing it to water.

7.) With the seal removed use the carb cleaner to remove old debris and grease from the cover, contact tracks and traces, and contact pickups. If their are signs of broken or severely worn tracks or traces then the part will need to be replaced. Mine was fine at 118K mi.
* Pay attention to the spring metal contacts as they may need a little bend back and work the springs on the arm contacts to ensure they will hold contact to the track.

8.) Apply new lithium white grease to the contacts and work the unit back and forth manually.

9.) Reassemble, reinstall, and if you broke the plastic tab to hold the body of the molex connector to tranny then improvise with new wire ties.
* Don't forget to reattach linkage.

10.) Turn key and test. The shift indicator lights should change seemlessly without flicker or jump to the desired gear. With the proper signal being sent to thru the computer to the tranny, shifts should be smooth.

*Note you may uncover additional problems in the transmission at this point that may have been preexisting or due to a result in continual wear from hard shifts relating to sustained fault in the mode selector switch. I've noticed that their is no longer an issue with down shifting however have discovered that my valve body, fluid pressure, or shift solenoid is causing violent shifting between 1-2 which wasn't eliminated with this fix since it had already been present. In either case I won't have to purchase a mode selector switch saving me $250:

SilverBullet75
08/20/2008, 10:28 PM
In addition... a remedy for future switch failures is to add Header Wrap to the exhaust pipe near the switch. If you have a bad one, you'll notice that the plastic mechanism (receiver for trans shaft) has melted a bit internally, which causes play.. ultimately causing this issue. A little less heat will make the newly installed unit last much longer.

Great write-up by the way!
Thanks!

AK Falco
09/03/2009, 10:06 AM
1172
The Mode switch just after it was removed.

1175
The mode switch all cleaned and DE OX put on the contacts

This is a great way to repair, clean the mode switch! the removal is simple and the fix works. I was having trouble with the dash indicator light (showing the car in reverse when in drive) but after cleaning the inside with Carb cleaner and using a DE OX compound to protect and enhance the contacts, I am happy to say that I am always in the right gear now!;)

By the way the gasket dose respond to temp. once mine was removed it expanded, in order to re install it i just put it in the freezer for 5 minutes. that shrank it up so it would go back into place.

Thanks kronopoliz for the write up!

Sprey
11/28/2009, 11:00 PM
Bump
My vx was starting to kick me when slowing down so ive pulled off this mode selector switch and have started cleaning it with a sensor safe product.

When appliying the grease do you put it along the contact lines?

Mine was pretty dirty inside had a build up of thick greasey stuff on one side.
Top of the piece on the left you can see a build up of thick greasey stuff and same with the bottom

http://i310.photobucket.com/albums/kk404/sprey16/IMG_1457.jpg

Ldub
11/28/2009, 11:16 PM
Looks like this is what AKFalco was using...http://www.alliedelec.com/Images/Products/Datasheets/BM/GC_ELECTRONICS/796-9839.PDF

I would think a di-electric grease that could handle high temps would also work.

Sprey
11/28/2009, 11:25 PM
Yea ill pop by the car electronic store 2mrw and pick some up.

hopefuly my problem will be fixed. Ive gave the whole lot a good once over hopefuly i didnt ruin it :p
Then again to be honest im sure a tranny flush would be good for it too.

Cheers dub :D

Edit

Finished it all today ended up using white lithium grease.
Took for a 2 min test run round the block and seems to be even changing gears smoother!

AK Falco
11/30/2009, 12:15 AM
Sprey, when I was cleaning the mode selector switch i was using a carb cleaner and a clean shop rag. once clean and dry I used a petroleum based compound that protects wires and contacts. it is an electrical product made to protect aluminum wires from oxidizing. it is an electrically conductive compound to it will transfer a signal or current helping worn contacts. the stuff I used came in a tube and is made by Illsco.

Also after doing the cleaning I flushed the tranny and filled up with new fluid. seeing the difficulty of checking the fluid level, this might not be something that a normal car owner would do on a regular basis. I believe that low fluid was partly to blame for my problems dealing with the jerking and gear light in the dash showing the wrong gear.

Sprey
11/30/2009, 01:29 AM
Ahh i see!
I ended up using a cleaner that can be used on Maf sensors so yea electronic safe. gave they a clean out and a wipe down basicly got all the stuff off.

and just applied bits of the lithium grease and made sure it was all smooth, at least now i know its all done.

But yea i agree on the tranny fluid im gonna get my flushed etc soon.
As i have no history of the car no idea what has been done in the past.

Tho ive had no dash light problems had the odd jerking gear.

basicly ive been slowing down to for a giveway sign. so like under 30km. and the autobox would drop down a gear then up then down again i think and that sorted like gave me a kick.

but yea ill most likely get it flushed soon.