Maserati 4200/GranSport Window Micro-Switch and Regulator Fix

So recently you’ve noticed you pull the door handle from the inside or outside of your car, and the window goes all the way down. Alternatively, it goes about half way down.  Then you get in and have to keep pushing the buttons in order to get the stupid thing up, right?

Maybe you haven’t a window issue like above instead you’ve heard a loud clunk, and now the window doesn’t roll up at all. You can just hear the motor turning inside the door but it’s not going anywhere.

Well, this article is hopefully going to help you out, and get you up and running again. If the welding, and or the micro-switch fix might be more than you feel comforable handling, but you don’t mind disassembling the door to get it out, or maybe have someone remove it for you. Please feel free to contact me, and I can send you a shipping label in order to fix it for you. The alternative to this fix is part number 387700050, or 387700051, you will see the part for each side is about $700.00 USD. The micro-switch is part number 980001800, this part costs about $140.00 USD

Causes

So what are the causes of these issues. There is a reason why I put these two issues together. It’s because if you are going to address one, I want you to address the other as well. If you don’t, you are looking for more headache down the road. I will address the micro-switch first then the structure of the window mechanism itself.

Now there are actually three micro-switches for the doors of these cars. One for the outside handle, one for the inside, and one on the frame of the window regulator that acts as a limiting switch for how far the window rolls down when you get in/out of the vehicle.

This last micro-switch is where the issue is caused, the window limiting switch. It’s very simple, the switch is intermittently failing so no longer cuts the power to the regulator as it should in order for it to stop the movement of the window:

Once you get the door panel off, I will show you how in a minute, you’ll see the water shield material. You’ll pull it off and you will have this little site window that’s above the yellow wire. In there you will see the micro switch that fails for the window.

The second cause of catastrophic window failure is the pivoting/rotating  frame the window regulator sits on. If you are in there because of the limiting switch, you might as well address the more serious issue of the frame itself. When this breaks you will either hire a fabricator to address it or be purchasing another unit. Both will dig into your wallet.

So you get a full picture of this issue, and again, I will get into disassembly later on, here is the full pivot/rotating assembly (above) that the window regulator sits on.  Additionally, you can see the micro switch sitting to the left of the tension spring, held in by rivets.

Here’s a photo with it flipped over (below). You will notice the new welds, literally within seconds of welding it, I snapped this photo.

Here are the welds with the bracket flipped over on the inside:

Here is a photo (below) of the three small tack welds that hold that geared part of the frame the regulator uses to rotate the rest of the assembly. This is why you need to weld it better, it’s the three round dots in the bracket. As you can see it’s just common machine tack welds:

So what happens to make the window not come back up is the regulator torque forces the toothed metal bracket away from the gears of the regulator so it no longer makes contact with the teeth. The spot welds are not enough to continue to keep the toothed part of the bracket secure like it’s supposed to be, in turn it rocks back and forth on the welds. In addition to this you could also have the spring hinge like this break:

The above photos are used by permission of a Client of mine. They show the eventual force busting the retainer where the spring hinge sits. I believe this is because as those tack welds loosen, the window regulator actually pushes the bracket in a way it was not designed, putting more stress here, eventually braking the bracket further down.

Above is a better look of where it broke. You can see the small bracket to the left of the photo (two small nuts) This is the bracket the limiting switch uses to toggle the power off. To the right you see the geared section where the regulator would sit.

Okay, so let’s cover some ground in order to fix these issues. First, obviously we need to disassemble the door panel, I am using GranSport door below. The 4200 will be similar.

Disassembly

Let’s start with the main metal molding piece above. After removing the above trim piece four brass colored screws need to be removed. Sorry I didn’t have a photo at this time. Before I forget DO NOT  use a metal screw driver to remove that trim piece and mar the finish or damage it. If you don’t have anything plastic, wrap black electrical tape around the small screw driver you are using.

There’s a tiny piece of plastic in the center of your door handle. Pop that out, and remove this screw (above). Next pull the door handle out, and pop the insert off.  After you do so, there will be a small screw holding a shiny metal bracket in, that’s attached to the door handle. Remove that one, it looks like the one above.

Okay so this screw should be obvious, just remove it.

Tweeter removed, look into the center, remove that screw.

Remove the speaker grill, then the speaker itself. You will see two screws on the top and bottom that must be removed like the above photo. The screws might be a different color but the location is the same. Additionally, if you have different speakers do not worry, I put these Alpines in a while ago, they are not OEM.

Pop out the reflector, remove the screw behind it.

Last, but not least, you will have screws on the very bottom of the panel, four or five that go all the way across like this one by the light. Remove all of them. Then you can pop the panel loose pulling out but then pushing up. There are metal catches to hang the panel on at the top by the window. Hold the panel there though. You still have to disconnect the bottom door light or you will mess it up.

Push the light out from the door panel and push the clasp to release the light from the harness. Then re-install the light into the panel so you do not lose it. Then set the panel to the side.

Next you’ll be blessed to remove the water shield material from the door. Best tip for you on this, use a heat gun on very low setting or a blow dryer on higher setting. Work it slowly to keep it together. Chances are you’ll rip it, but it’s the thought that counts!

Two 8mm bolts hold the window in. Loosen these, pull the window up to the top, you don’t need to remove the window.

 I didn’t have a plastic trim tool nearby when I took this. Plastic is preferable. I instead had a screw driver with black electrical tape wrapped over the bottom. Remember, glass and metal never mix well. But you’ll see the access hole (above) I stuck the screw driver through to hold the window at the top of the door.  The plastic you use must be long enough to insert all the way to the other side. It is sitting under the window edge. If you don’t trust yourself with just one, there is another access hole (below) you can also stick another object through:

Don’t worry if the plastic window retainers drop down, like above. It would be better if you just removed them and sat them out-of-the-way anyway. Note their orientation when you do so, or come back and look at these photos.

Okay, so first you will be removing these two 10mm nuts from the center support bracket. Please mark one of the studs and it’s location. When you remove the entire bracket from the window it can rotate around, and you can get confused of its correct orientation when putting it back in. It actually was already done for me here. The black adhesive puddy was already wrapped around the stud.

Additionally, the puddy is also covering a slotted mounting hole. This is important because, if you mark right were the nut sits, you will know how it aligns when you put it back in. Mine sat all the way on the bottom of the mounting slot. If you don’t mark it you’ll see the window will jam as you try it out once re-installed. You will then have to keep playing with it to get it where it needs to be.

Finally, the last four 10 mm bolts of the window regulator assembly above, however before you do this you need to also reach into the speaker hole and detach the micro-switch harness like so:

Also detach the harness from the regulator itself, you can detach the frame now as it will be easier to feel for this harness. As a picture was hard to obtain inside the door, this is where it would be located (below), sorry for the alligator clips, that’s for another trick later on. This was the only photo I had to orientate you where the harness will be located:

Finally, collapse the assembly like below or you’ll never rotate it out of the window,  here are step by step photos:

Now, all you have to do is remember the reverse of what I just showed you to get it in! Good luck…lol. BTW, don’t dig up your door. It will come out, just be patient.

Micro-Switch Fix

I’m going to detail the easier fix first but I recommend that you weld the geared bracket before completing this. If you don’t, or can’t do this, again I don’t mind you sending it to me.

Now micro-switches are nothing new for automobiles. You don’t need the one Maserati sells for $140.00. Actually just the opposite, I would recommend any brand other than OEM because the ones they used were quite cheap.

Before I get into the rest of the micro-switch let me tell you how to remove the old one.  You’ll need a 5/64″ drill bit, and you will drill out the old rivets which I show above. Do it from the front side where the old micro-switch is. Then remove the plastic hold downs that hold the wire harness in place. That’s pretty much it, it is a simple process here.

Next the photo above also shows how I laid the new switch over the old one to ensure it was the right mounting point, and alignment.

There was a gentleman, that fairly recently, covered just the micro-switch fix on Maseratilife.com. My fix, I would suggest a few things a bit different. First, he covered just the switch fix, and not the bigger problems which I’ve detailed here. I don’t think you should only fix the switch and not fix the assembly itself because you will have bigger issues later on. Additionally, it’s a whole lot easier to take the assembly out and fix it correctly. But again, it’s your car, your prerogative. I’m here to give you the information not make you accept it. That being stated, I suggest a pronged micro-switch like below. Use speaker connectors or the appropriate wire connector to splice into the harness. This way, should you damage it by accident, or alternatively need to again replace it, it is an easier disconnect, instead of making multiple splices into the wire harness and shrink wrapping the wires. Before I forget, you should also shrink-wrap the connectors below, or wrap them in black electrical tape, just to be sure nothing metal bounces off of them.  They do have plastic covered connectors that will work on these as well.

Once you are done you can install this back on the rotating assembly. I just used the same size long rivets. I used stainless steel but you can really use just about any rivet long enough that goes through. Additionally, if you’d like to use long small bolts you can do that.

Here are some photos side by side with the micro-switch I used with OEM. Don’t worry about it being smaller, just check for the diagonal mounting configuration/spacing.

I almost forgot a pretty important detail, when you wire these. You will notice there’s three prongs and I used the two outside prongs. That’s because of the multi-uses of micro-switches in general. Because our car windows’ are using it as a limiting switch, you will need to make sure you use the “com” prong, and the “NC” (Normally Closed) prong on these type of switches. You don’t have to use the switch I have, though you can buy them for like $10 for a pack of 5 on eBay. Use whatever micro-switch you want, now that you know how to wire it. Just make sure you use those prongs.  If you wire it on the wrong prongs,  power will only go to the regulator when the switch is depressed. So the window won’t work at all wire this way. Wired correctly, it will cut power with it depressed, thus limiting the movement of the window down to an inch from the top. Additionally, it’s not pole sensitive so you don’t need to worry about which wire is on which of the “com”, “NC” prongs.

Now if you remember I showed you a picture above of plastic covered alligator clips sitting in the harness part of the window regulator. Well that’s so you can operate the regulator out of the car. Just attach the alligator clips to a 12 volt source, I used a battery, then reverse the leads to make it go the other way. I just attached one lead, and touched the other when I needed to rotate it, then reversed them. If you want to get technical you can build a switch for it as well. It’s not necessary but it’s your project so do as you’d like. You will need to rotate this back and forth to align the bracket before you will weld it as well. Here’s that photo again.

Fixing the Regulator Bracket

Buttressing the spot welds on the regulator bracket is extremely important if you don’t want your window sitting inside the door. I’m going to cover two parts here that may need to be attended to. The second one you will only fix if it fails, the first you should do as preventative maintenance.

Again from above this is the spot welds that loosen up and fail. Basically what happens is the torque of the motor, and weight of the window pushes the entire bracket down away from the regulator teeth until it no longer contacts them. With no grip from the teeth it can no longer roll up or down, therefore falls.

I weld it in two places. along the ridge between the top of the two metals, which I think would be sufficient, but I also flip it over and put two welds inside.  Like so…….

If this hasn’t failed, still works perfectly, and you are doing this for preventative maintenance, just weld it up like above. It should already be aligned where it needs to be.

If it has failed, you need to take a small hammer and tap the gear teeth towards the regulator teeth to make sure when you weld it, you don’t weld it wrong. Once it’s welded wrong you will be cutting all of the weld in order to re-align this.  You need to tap it from both ends, run the motor both ways to make sure it’s gripping like it’s supposed to.

I want to caution you again to check to make sure that it’s aligned before you weld it, by bench testing it with the tips I listed above for moving the regulator.

Now, some might try to read this, and say “I don’t need a welder. Let me try bolting it or using rivets”.  Let me help you lay that to rest. First, you don’t have the clearance to try bolting through both brackets because when the regulator moves it comes to a point they rotate within about 1/8″ of each other, like scissors. Secondly, I tried putting stainless steel rivets in one, four rivets to be exact. The torque created from the regulator made short work of them twisting them just enough to push the teeth apart. In my opinion you should weld this area. It’s strong, durable and will never be a problem area again.

Okay so here is the second fix. The regulator snaps the rotating assembly beneath the tension spring like so:

Notice the grooves in this above as well. It’s so the spring as the window rolls down gets tighter and helps the window back up on the upwards cycle. So here is how that was addressed:

Now, of course before all of this happens above you’ll need to be sure you place everything into the correct position. The only suggestion here is, if you get lost, open the other door panel up and look at that one.

Again I will add, if you want help and would like me to weld it, or fix it please contact me. I will arrange for it to be shipped here and to be fixed. You will then re-install it when you get it back.

I hope this helps.

About Post Author

craigwaterman11

craigwaterman11@gmail.com

https://craig-waterman.com

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