Fixing Power Windows And Door Locks On An Old Maserati Is Hell

You ever start a project on a car that you expect should only take a couple of days only to have it drag on for a month?

Yeah me neither …

Oh wait! In my intro to my Biturbo cheap car challenge road trip project, I mentioned my first steps were to get the door locks and windows working. Why? Because I wanted to be able to actually secure the car. If I go through all the trouble of getting it running and driving properly, it would be really annoying if someone stole it or something out of it. Additionally, I have no doubt the air conditioning isn’t working, so I’d like to be able to roll down the windows when I’m testing it and have some degree of confidence they’ll roll back up.

So I Spent a Month Working on Windows and Door Locks, Somehow

This Maserati, like my 1984 Saab 900 Turbo, shipped with a key-actuated power lock system, rather than the wireless power locks we’re so familiar with these days. Operation is pretty simple; when the driver’s door is locked or unlocked with the key, this triggers the other doors to do the same. The issue with my Biturbo is, apparently, it contains some sort of positive locking circuit that is apparently malfunctioning or otherwise unhappy. When I lock the doors they do indeed lock, then unlock, then lock, over and over until I unlock them from the key again. Documentation is thin on how the system operates, but my best guess is the system is checking if all the doors are locked and if they aren’t it keeps trying to unlock and then relock them. Forever. (This isn’t exactly how the system works, but we’ll get to that.)

This isn’t ideal but seemed like it would be a pretty simple problem to solve. I know the rear driver’s side door lock is hard to operate, so that seemed like a good place to start. Also I figured “while I’m in there” I’d service the power windows, knowing old power windows do not like to sit, especially out in the Oklahoma sun. The grease can dry up or harden, causing the mechanism to jam or destroy itself, which wouldn’t be ideal. Ask me how I know.

Unfortunately despite knowing damaging the regulators was possible, I still thought that I should test them before I serviced them. I have no idea where this level of cognitive dissonance came from, but as I’d just bought one of the most hated cars of all time you could argue I lack an abundance of common sense.

Both the front windows rolled down but neither would roll back up, instead making horrible grinding noises. Oops. “Luckily” the rear windows were inoperative, so they were spared my idiocy. Terrific.

To add complication, the service manual that came with the car was manual 1 of 2, covering the engine and transmission but none of the internal trimming and things needed to take the door cards off. While I was happy to have the one, and the other was eventually located, this also meant that I was going to have to wing it on removing the door cards. Luckily, this isn’t my first ’80s car rodeo. After some exploratory prodding with a screwdriver, I was happy to discover the door cards are pretty uncomplicated in the Biturbo, basically being held in by about six screws and a few clips. The only piece which really gave me trouble was the door handle itself, which had corroded to the spindle and took a fair amount of convincing to remove.

However, conquering that particular monster using a prybar and more force than I was comfortable with, I had the door card off and the suspiciously familiar looking door lock actuator out.

To my surprise … it actually worked just fine, and after a little manipulation so did the all the other locking features of the door. Additionally, the actuator itself didn’t seem to have any ability to feedback its locked or unlocked status, and there didn’t appear to be any additional sensors or contacts in the door or latch to tell the system the door was locked or unlocked.

Which is curious.

For lack of any better direction, and knowing the front windows were now stuck down, I started removing the driver’s front door card to see what I could see. Knowing the driver’s door lock worked, I ignored it, (which was stupid, but I did it) and immediately started looking at the window regulator. The regulator is a cable operated design, sort of, with the electric motor driving a small cog, which interfaces with a spiraled coiled cable with a soft fabric-looking core, forcing it through a track and pushing/pulling on the window carrier, which moves in its own track. While I’d never seen a design like this before, new replacements weren’t available and used replacements were expensive, so I opted to take it apart to see what I could see.

After removing the motor and cable from the assembly, the news was not good. As you can see above, the cable had a small area of damage, where motor gear had removed some material from the cable to the point where the two can no longer interface. Unfortunately, the passenger front cable was even worse, looking basically shredded.

So… not great. Fortunately, the community provides, and aftermarket new cable replacements were available. I, foolishly, thought I could fix the driver’s side by rotating the cable 90 degrees, which was a good thought but didn’t work, forcing me to order a second cable on a different order. Luckily, my assumption the rears were “fine” was accurate, as after removing the remaining door cards and disassembling the regulators, I found the rear cables to be in good enough shape, only hampered by a little rust and a lot of old grease. A trip through the parts washer and some fresh grease had them reassembled and working, at least on the bench, in short order.

While I was waiting on the parts to reassemble the front regulators, I returned focus to the door locks. You know, the original reason I opened this can of worms.

With the door cards off, I was able to verify the operation of all the door locks… except the passenger-side front lock, which didn’t seem to be moving. I could see it twitch whenever the system activated, but nothing was actually happening. I pulled the actuator and made a few interesting discoveries. First, the front actuators were different than the rears. While the rears were both two wire, simple actuators, the fronts had five wires. This was, presumably, how the door lock system was able to tell the door were, in fact, not locked. I guess it just doesn’t care about the rear doors, likely owning to the car originally being designed as a two-door, though that is just speculation. The second revelation was this actuator was in bad shape. Though I could get it to move by applying significant force, the mechanism felt like it was full of broken plastic, likely because it was. Unfortunately, the actuator was riveted together in such a way which made it look like opening it up would be a bad idea. To compound matters, spares seemed thin on the ground, with no specialty websites I could find offering them for sale.

But the actuator did look really familiar …

A quick search of the internet revealed the actuator was pretty darn generic and still sold as a new way to add power locks to whatever you feel like. Though the two-wire variant was far more common, I was eventually able to source a 5-wire actuator for a whopping $8 at BezosMart, including overnight shipping.

It couldn’t be that easy, could it?

Well … yes and no. After some testing to confirm the actuators were wired up the same, I spiced the old connectors onto the new actuator and plugged it into the car with mixed results. On the one hand, the system wasn’t stuck in a loop anymore. On the other, for whatever reason this actuator didn’t have the ability to command the system to lock/unlock. Unsure what the difference could be to cause that, I decided I didn’t care if the passenger door could activate the power locks and installed the new actuator. Despite needing to drill some new mounting holes to accommodate the slightly longer universal replacement, the install went fine and I now had four working power locks!

All this work on the door locks took long enough, the window cables, and a host of other random parts, came in! Throwing the instructions into the bin, I lubed up the cables and slid them into the newly cleaned channels. With surprisingly little fuss, except for the hour I lost looking for misplaced hardware, the regulators were assembled and, eventually, put in the doors.

Now, that sentence was really easy to type, but in reality that amount of wrenching took several hours spread over several days. The downside of working full time and also having to exist as a human, is I can really only afford to be at the shop for a few hours before social or home obligations call me back. When this project gets to crunch time, I’ll go full shop hermit, but we’re not quite there yet.

The biggest headache of putting the regulators back in, aside from accidentally bending the delicate cable channel… several times, was the wiring for the door locks feeling left out and like it needed to be involved. Functionally this meant they kept getting tangled in the regulators as I got them installed, which wasn’t annoying at all.

The (not actually) last step was to get the window glass itself aligned and attached to the refreshed regulators. This proved… challenging, with the old witness marks offering little help and the whole mechanism having far too much adjustment for my own good. I, eventually, got it where I was happy with the seal, open, close, and movement. Some of the glass still seemed hesitant to move through the channel, but I think that is a combination of dried seals and lack of track grease.

The actually-last step, or so I thought, was putting the door cards back on. They’d been sitting in the trunk for several weeks at this point and were looking a little sorry for themselves. As such, I went ahead and cleaned and conditioned the leather of each piece as I put it back in, trying not to get any additional grease or oil on the suede inserts.

This process, of course, was not as straightforward as I’d hoped. The first snag was installing the driver’s side upper door card without first reconnecting the door lock pull tab. This, however, was easily remedied and I didn’t make the same mistake on the next one. I made an entirely different mistake, installing the upper door card without a vapor barrier… because the one that was in there had disintegrated when I removed it. A quick run to Home Depot for some plastic and I had a pretty decent vapor barrier.

Yes, butyl tape probably would have been better than duct tape, but I hate the residue and resent having to either bathe in acetone or remove all of my skin manually after working with it. Anyway, bonus points for the commentor that sees what mistake I made when installing that vapor barrier!

Anyway, in a fit of competency, I realized while I’d declared the door locks fixed, I had no recollection of testing all of them. With two of the four doors fully reassembled, the best time to test would have been two door cards ago, and the second best time is now. I hooked the car up no power shut the doors, and tried them. Good news was three of the four locked fine and two of the four unlocked fine! Sadly, the passenger rear was completely non-functional, only making sad little twitches when activated, even when using an external source. The driver’s rear would lock but not unlock, but since that door car was already back on, I decided I don’t care.

Just kidding! You should know me better than that. The replacement for the rear passenger actuator was a 2-pack, so I went ahead and pulled the rear driver’s side door card back off and installed the new actuator. Now with three cheap aftermarket actuators installed and one original, I’m sure this will be the last of my problems!

As I re-re-re-installed the door cars, I went ahead and conditioned the rest of the leather in the car while I was contemplating my choices in life and, aside from a small seam rip in the driver’s seat, am impressed with how well this neglected example has held up.

So How Long Did All of This Take?

Too. Damn. Long.

Despite how this is presented, I split time between the interior and working on the engine, but two months later my “one week job” is almost nearly completed.

Not ideal, but, sadly, far from the worst project drag I’ve experienced.

What’s Next?

Now that the windows and door locks finally work, I really, really need to tear into the engine. The car doesn’t like to start, doesn’t like to idle, and doesn’t like to rev. On top of that, there is a loudish ticking noise coming from the engine that could be a valve issue, injector issue, or something much, much worse. I also should look at getting the timing belt cover off as I imagine that hasn’t been looked at in at least 10 years. I went ahead and spent the money on a new belt for peace of mind, but wouldn’t say no to not having to do that.

I still have a little bit of time before my trip to get this car sorted, but losing three weeks to something as simple as door locks and windows certainly has me down. There are also a lot of lingering electrical demons, as I still have to wiggle the fuse box to get the car to start sometimes.

I’ve probably got this, but I also wonder if this Maserati is going to be my Icarus moment. Every cheap car challenge trip we’ve done my cars have had more and more mechanical issues as I get less lucky and more ambitious. Frankly it was a miracle that my neglected Alfa Spider made it to Seattle and my Discovery didn’t miss a beat despite both head gaskets being blown, but both made it without complaint. However, the Piazza in 2023 was my first real break down when the fuel pump heat seized in rural Oklahoma, requiring some creative driving, a lot of phone calls, and, paradoxically, a speeding ticket, to be able to get to the start line in Kansas and get the pump replaced. While I still have time to vet (I can’t believe that is the correct spelling there) this car before the trip starts, there is just so much that could go wrong in this maligned 80s monster.

At least the fall will feel a lot like flying.