Topic: reverse lights on r150f

[beyondlogic]

i changed me reverse light switch cause it was broken and leaking, and now when i shift to reverse the backup lights come for a second then go back off.  i've put the old plug back in and it does the same thing, i've also bypassed the switch and the lights work fine.

[Marlin]

What you have is oil fouled contacts.

The switch has an internal o-ring that seals the pin and keeps the oil away from the internal contacts.
Your o-ring has failed, allowing gear oil to get into the contacts and damage the connections.

I once was able to fix a t-case switch in the field by blowing compressed air in the gap between the pin and the housing as the pin is depressed and released. I also sprayed carb cleaner and was able to get the switch working as a result.

I have never tired to repair a trans switch, we just replace it with a good switch.

We have many used switches in stock. Give us a call...

Marlin

[beyondlogic [OP]]

well i have replaced the switch with a brand new one and it does the same thing.  is it possible for the rod inside to be worn enough that it doesnt depress the switch?

[Marlin]

When you shift into reverse, the shift rod moves forward and depresses the pin until the contacts make connection.

Do you have a thin aluminum sealing washer under the plug?

There is no way the heat treated 14mm rod could wear out.
If your trans in going into rev, the rod must move and depress the contacts.

I am trying to think what can cause this situation.
Do you have an aftermarket alarm?
Messed up, oil soaked wiring?

Remove the switch and test it by holding the switch in your hand and depressing the pin. If the lights work then it would have to be in the transmission.

Next, you will need to look inside the shift light hole, and see if the rod is in fact moving proper.

I have never heard of this before.

I will look at a core trans in the AM.

Marlin

[beyondlogic [OP]]

Thanks for your help.

it does shift perfect into reverse, it doesnt pop out or anything.

no alarm

was messed up from the first switch shorting out, but i cleaned it up and taped it, i may try to change the wiring this weekend.

[82rustbeast]

do you possibly have a digital multimeter? If you do and it has a way to check continuity, usually where the meter will beep if there is continuity present, check that on the light switch., either out of the tranny in your hand or in the tranny with the truck in reverse and the key on, but of course the truck not running.

My dad had the same exact problem on his r150F tranny. His problem was that there was oil in the pigtail connectors contacts like marlin mentioned.

We sprayed it out with brake cleaner, cleaned it all out, and it works perfect now.

It might even be a possibility that the new switch is defective. If there is no continuity on the switch with it out of the tranny depressed in your hand, it is very possible that its defective.

Other than that, the back up lights, I think, are part of the tail light circuit and there is no relay. Ant the fuse I think is shared with the tail light fuse.

Hope this helps

[THK Matt]

this helps for why my dads 95 4runner reverse lights don't work. I replaced 3 sets of 194bulbs (think thats the ones they use) and still no reverse lights at all!

he has lots of motor oil slung under there (leaky valve covers, oil pan, and timing cover)
I'll go clean the connection up under there and see if it works.

[beyondlogic [OP]]

i cleaned the pigtail a little this past weekend but still no good.

the wiring was really messed up from the orignal switch shorting out, so im going have to untape it all and check all the wires.

[THK Matt]

I have to buy a new switch.... it melted the inside of the switch.

[82rustbeast]

but, beyondlogic, dont the light work if you just bypass the connector? wouldnt it just be the contacts or the switch?

[beyondlogic [OP]]

um im not sure i havent been able to do much testing on it since i started this thread,  everything works a split second right when i put it in gear.  but my mom had some heart problems this week so my dad hasnt been around to help(press the switch while i watch, that kinda thing).  im hoping to maybe get more testing done this weekend.

[THK Matt]

but, beyondlogic, dont the light work if you just bypass the connector? wouldnt it just be the contacts or the switch?

the connector clicks onto to metal prongs on the threaded switch.. I think that'd be a negative.

[joeczabaranek]

When you shift into reverse, the shift rod moves forward and depresses the pin until the contacts make connection.

Do you have a thin aluminum sealing washer under the plug?

There is no way the heat treated 14mm rod could wear out.
If your trans in going into rev, the rod must move and depress the contacts.

I am trying to think what can cause this situation.
Do you have an aftermarket alarm?
Messed up, oil soaked wiring?

Remove the switch and test it by holding the switch in your hand and depressing the pin. If the lights work then it would have to be in the transmission.

Next, you will need to look inside the shift light hole, and see if the rod is in fact moving proper.

I have never heard of this before.

I will look at a core trans in the AM.

Marlin

Hey Marlin,

A Google search turned up this thread for me.  Im new to the forum.  I have a similar problem.  My reverse lights dont come on when I put my R150 in reverse.  For a while they would come on if I held the shifter aft & passenger.  Now they dont come on at all.  My original switch has continuity when I depress it by hand as well as the aftermarket switch I purchased.  I dont have any problems with the trasmission popping out of reverse and shifting still feels normal.  The only thing I changed was my transmission and transfer case fluid.  After 14 years and 120k miles I drained the old Walmart dino fluid and replaced it with Redline MT-90 synthetic.  That caused my transfer case to start leaking but I cant imagine it would affect the reverse rod.  Do you remember if you ever found something that could cause this?

Thanks for the help

[Stuckinthe80s]

Curious as well.