I have a 1992 S-10 Blazer, it's a 4x4, two door. 4.3L 4 speed auto.

The 4 speed auto is the important part here, because it's a little confusing with the situation, and I have another problem that could be connected.

When I put my truck into reverse, I don't get my back up lights. However, if I put it in neutral, they come on. even with the little bit of play you get between gears, if I put the selector as close to neutral as I can while in reverse, i still can't get my back up lights on.

More background, and another problem that this may be connected to, I don't have park. As in, I can't shift into it. At all. Even if I go under the car, and try to shift it into park straight from the transmission arm, I can't get into it. I'm sure I could somehow, but I'd rather not force it, as the car is pretty much all rust and I don't want to snap anything off, in case it's that weak.

I don't really know if there's something I can adjust to get park back, or if because I don't have park, something adjusted so that everything electrical moved one down, and that's why I can't get my back up lights in reverse, if I'm not being confusing or anything here.

I'd really appreciate some help or advice, thanks!

 

i cant remember the correct name right now so hopefully someone will correct me or know what im talking about and chime in. down on the side of the transmission were the shift cable goes into, there is a sensor with a big plug on it and 6 or more wires going into it. i think your issue is down within that sensor because that tells the transmission which gear has been selected and it sounds like you have a short in it. it was a common thing on the 4l60e. im havin such a brain fart i cant remember for the life of me the name of the part.

 

I think Ford called it the MLPS, I'm not sure though, my F150 was two year before they added anything electrical to the AOD.

Does that ring any bells?

 

yes it does. the neutral safety switch aka mlps. have a look around on google and see if you can found something that shows you how to test it. dont wanna see you replacing parts and it turns out thats not it. but i think you should start there first.

 

I gave it a shot, but a new one didn't bring park back. I could still start the truck in reverse and OD.

I did find that you can adjust it, once I found it on the steering column. But all that did was bring back my reverse lights, which was all I honestly wanted, lol

 

hmmmmm not too sure what to tell yea, well at least you got reverse lights. when you say you dont have park what do you mean? because if you dont have park than you cant remove the key from the ignition. can you remove the key? im a little confused!!!

 

I can remove the key. I just don't have park. The transmission won't shift into it, and the car starts in reverse and OD, instead of park and neutral. I have to wiggle the column sometimes to get the key out, but it comes out freely, not like I'm about to pull the whole ignition chamber out.

I'm confused myself, I've just never questioned it. lol

And it's actually in gear when I start it. I can either start in reverse, and be ready to roll right out of my driveway, or in OD, ready to roll right out of a parking spot.

 

The first thing you need to do is get the transmission position switch/sensor properly adjusted. It controls both the reverse lights as well as senses when the transmission is in park or neutral to allow the vehicle to be started. It sounds like yours is shifted too far towards reverse. Watch the linkage as you shift the transmission from park through to low and move the transmission position switch in the opposite direction. I have posted the adjustment procedure in the past. The basic gist of it is that you want to be able to start the vehicle in park and neutral only and the reverse lights should only illuminate in when the transmission is in reverse.

The transmission position switch is located on top of the steering column under the dash on the older trucks.

If you disconnect the shift linkage at the transmission, can you get it to go into park then? If so, then you may have to adjust the shift linkage at the firewall.

 

I've gotten under the truck and tried to put it into park, but I didn't want to force anything. I didn't disconnect the linkage though, I didn't think I would be able to through the rust.

My back up lights do only illuminate when I'm in reverse, but still no park. Should I grab a buddy and say "watch the lights" and adjust it as close as possible to turning on in neutral, but still turning on in reverse? I have it set so that it's not all the way to the left (reverse, I guess) but my lights are still on.

 

I'm going to guess my issue is more linkage based, and the computer is doing something as a failsafe through the TPS/MLPS/NSS, because it physically won't go to the park position on the column, or from under. I can't even get the indicator to it. It's not that it won't shift in, even if it's indicating it is, it just doesn't go in.

Edit: I guess TPS isn't the correct acronym, I should just say the full name, lol, we're not dealing with throttle at all...