dbbowen

Hello yall,

I have a 1987 4runner auto (a340f) havent gotten around to do the swap for my manual yet.

My reverse lights randomly went out and after hours and hours of searching, I have come to the conclusion that:

1.) since its not the bulbs, its probably the switch on the transmission itself
2.) its not a fuse, because my other lights (license plate etc) work
3.) Its not my neutral safety, because I can not start my truck in gear.

Every place I look has instructions on how to find the plug on the transmission of a 5 speed, Can anyone help me find it on my automatic? There are a few plugs down there, none of them I can seem to actually get off (they have a rubber protector on them, and dont seem to want to budge off of the transmission.)

I feel like it has to be one of the plugs on the front of the transmission on the drivers side. If anyone has photos that would be an incredible help.

PS. All of my plugs are connected, I dont have any random dangling plugs on the transmission or the other side of the wiring harness near the starter. Everything seems to be plugged in, and the lights worked last week. We did have TONS of rain and some light flooding last week, maybe the water shorted something out???

rustypigeon

The PNP switch controls the reverse lights. It is the switch with multiple wires connected to it located where the shift lever comes oit of the transmission. Check for continuity between terminals RL and C with the transmission in the R position. This link has a diagram with the terminal labels...
https://acad-eng-gen.ca/ether3al.com.../9parkneut.pdf

dbbowen

Thanks, Ill have a look at it when I get home from work. The link didnt want to work on google chrome. I take it, that this is on the passenger side of the transmission?

rustypigeon

Yes. Passenger side.

Look like the link is made for mobile devices. If you don't have a moblie device that can view it, I will post an image of it when I get home.

dbbowen

I have been looking at pages where people have removed it and cleaned the gunk out of it, maybe this is the issue. Or a wire is shorted or something. Thanks for the help

RAD4Runner

A multi-meter will answer your questions.

dbbowen

Located the pnp switch thanks to rusty pigeon. I took the switch off of the trans and cleaned up the gunk built up around it and where the wires enter the switch. All fixed. Thanks y'all for the help and info

dbbowen

Ah crap, Stopped working again... BUT I figured it out. The linkage that connects the shifter to the PNP sensor is loose and not turning the sensor enough to engage the light, but it engages it enough to activate reverse. If you put the shifter in reverse and push up onto it a bit, the lights come on. Im planning on swapping to a w56b whenever I get the labor money to have the trans installed anyways so Im not getting back up under there and messing with it again. Oh well.. Hopefully if anyone is looking to figure out why their reverse light on the a340f and a340h transmissions this might be your problem, unless you have a wire shorted somewhere or your switch is bad.

kitmaddox@yahoo.com

1985 Toyota Truck 4WD Automatic transmission (A340H)... saved $300 on a new switch;
I had no backup lights... followed the instructions in the video below and it worked like a charm... appears to have fixed my intermittant cranking problem as well

dbbowen

I fixed the problem by swapping to a manual lol. I tried to remove this like this video and couldnt get the pigtail to unplug so i said forget it! lol