When i put my truck in reverse the lights will come on for a second and shut off they will come back on if i push up on the gear shifter but moments later shut off again.

 

Readjust the Park/reverse switch. I believe it is located on the trans.

 

Where would that be?

 

its called the neutral/safety switch. its on drivers side of trans, near the front, where the linkage is. it has an electrical connector. it moves with the linkage and has 2 functions. it locks out the starter when trans is in any other gear than park or neutral. it also turns on the backup lights when in reverse.

that swith might be bad. you could probably test it with an ohm meter.

 

Alrighty thank you and ill update you tomorrow on what happens with it.

 

Perhaps I should start a new thread but here goes anyway.

Backup lights do not work OR have worked to only flash once in awhile.
No amount of jiggling the shift lever assures the backup lights will come on or stay on.

I removed the old "neutral safety switch" and replaced it with a new one. No success.
I tried yet another new switch. No success again! What I have read a hundred times now,
is change the switch (after the linkages are checked. Linkage is OK). Park and Neutral works are they are supposed to, to start.

Only the Back-up lights are the issue!

I tried, with an Ohmmeter to see what these switches behavior is with the 3 pins.

Indeed, the switch center external pin is connected to the tiny tip on the switch's internal pin, the one under spring tension inside the plastic which is also under spring tension. If you have seen it, you know what I mean. I assume then in Park and Neutral, the cam or whatever inside the trans presents a conductive tip to the switch to allow the starter to work. I can see and feel in the hole a small "tit" on the cam in both Park and Neutral. To the trans surgeons among us, is this analysis correct? Anyway, this function works as expected.

The switches 2 external outer pins (for the back up light function) are electrically connected when the internal spring tips are fully extended but when compressed, the outer pins go open. In the trans hole I can see a cam that looks like there's an indentation when the shift lever is in "R". This then, I suspect, allows the switch springy internal tips to stay extended, completes the circuit (closed) and the back-up lights go on? Any other shift position, the tips are compressed, the circuit goes open, back up lights off. Surgeons?

With the switch is installed, the back up lights don't work. It is AS IF, the springy switch tips are compressed which keeps the back up lights circuit open. I can unscrew the switch and get correct closed circuit. Makes sense? With the switch torqued in correctly, the circuit remains open. No lights. It's like the internal length of the switch is a tad too long.

Anyone have any insight as to what's going on? Or solutions.

Thanks

 

When you unscrew the switch some, the lights work? Or just with the testing procedure? I assume you checked all the wiring at the rear? Including the sockets themselves.

 

I must confess I have not yet gotten up and tried the lights with the switch unscrewed some. I'll do that but I am not hopeful.

What the Hayne's manual says is unplug the switch connector, use an ohmmeter to check for continuity between the center terminal & the case (ground). Continuity should only exist when the transaxle is in Park or Neutral"

This passed the test for each of the three switch trials. I did make sure the linkage adjustment between the driver's shift lever and transaxle lever were correct.

Then Hayne's says check continuity between the two outer terminals. Continuity should exist only when the transaxle is in Reverse. No continuity should exist between either outer terminal and the case.

If the the neutral switch fails any test, replace it.

All three switches, screwed in, do not show any continuity when in Reverse when they should, if all is correct. It's when I back them out a turn or so, that the continuity returns.

From my tinkering with the bare switches, trying to understand what's going on, the conclusion is, the switch normally remains compressed in all shifter positions except in Reverse. Then the lights should light.

I am thinking there's something awry with the cam itself or at least the Reverse indentation I can feel. The circuit is simple so it shouldn't be this perplexing. Either I am really missing something simple OR there's something internal to the transaxle that is not right?

BTW, I did probe the connector outer terminal holes and showed continuity which should mean wiring all the way back to the lights are OK.

 

All I can say is, that if they work when you unscrew the sensor some, then obviously there is no wire problem. If it only works when you are testing at the switch, then the problem has to be at the back. Stating the obvious I know. Other than a worn cam or whatever in the the tranny.

 

The comb that actuates this switch appears to be pretty sturdy. Cannot imagine it getting jacked somehow so that it will not operate switch. If the trans still shifts from park to neutral, to drive correctly, I cannot imagine what would be wrong inside. Maybe the swith makes connection while testing, but vibration while backing loses connection. May be worth checking continuity while shaking switch around?