Buick Lucerne Servicing Guide, Part 1

May 1, 2008

The Buick Lucerne (Photo 1) was introduced in 2006 as a replacement for the LeSabre. Like the LeSabre, the Lucerne has become a favorite with the rental car companies, which can be a real headache for locksmiths. General Motors and the other manufacturers sell a lot of vehicles directly to the various rental car fleets and manufacturers will often use up their old stock of parts on these cars. An example is the 2008 Chevrolet Malibu Classic, which is essentially a 2007 Malibu that is only being sold to the rental car fleets.

The photos used in this article were taken in 2006, shortly after the Lucerne was introduced. At that time, the Lucerne was equipped with locks manufactured by Ortech. Later, Ortech replaced the 75 groove locks with the 93 groove locks. However, GM continues to supply some Buick Lucernes to the rental car companies that were equipped with Ortech 75 groove locks. And of course, these vehicles are eventually sold to consumers, which complicate things for us.

If you are going to generate keys for, or rekey a Buick Lucerne, the first thing you will have to do is identify which lock system you are dealing with. If you have an existing key, that is fairly easy, but if you do not, the easiest way to tell is to simply try the two different key blanks. For the purposes of this article, I’ll be discussing the Ortech locks, since that was what this particular vehicle used. The procedures for unlocking and removing the locks from the vehicle are identical regardless of which lock system with which you are dealing.

The easiest way to unlock the Lucerne was through the rear door using the long end of the TT-1008 tool (Photo 2). The Jiffy-Jak Vehicle Entry System can also be used on the Lucerne, but attacking the rear door as shown below is much faster and easier.

Begin by inserting two wedges about 6 – 8 inches apart, slightly forward of the outside handle on the rear door. As you insert the wedges, be sure to use a plastic shim to prevent the lower layer of the weather stripping from rolling under the wedge. If the weather stripping rolls under, it will make your job harder and may damage the weather stripping. (See Photo 3)

After you have a gap large enough to insert your tool, slip the long end of the tool into the door between the wedges. Once again, the use of a plastic shim as shown here will prevent the lower edge of the weather stripping from rolling under as you insert the tool. Once the tool is inside the door, lower it about eight inches and then rotate the tip of the tool to the inside of the vehicle. While keeping the tip of the tool as far to the inside of the door as possible, pull up on the tool until it hooks onto the horizontal linkage rod inside the door. (Photo 4)

With the door panel removed, you can see how the tool hooks onto the linkage rod. (Photo 5) The linkage rod is exposed for a long distance through the opening in the inner skin of the door, so precision placement of the tool is not necessary. Once the hooked end of the tool has hooked around the linkage rod, twist the top portion of the tool so that the tool binds the linkage rod. If you do not bind the linkage with the tip of the tool, then the tool will just slide along the rod instead of moving the rod.

Once you have a good grip on the linkage rod, lever the rod to the rear by moving the top portion of the tool toward the front of the vehicle. I hold one hand on the tool near the weather stripping as shown here to act as a pivot point for the tool. As you move the linkage rod you will see the inside vertical lock button come up to indicate that you have unlocked the door. (Photo 6)

As on many of the newer vehicles, the only exterior lock on the Buick Lucerne is located in the door handle of the driver’s side door. Removing the lock requires the removal of the inner door panel. This panel is fairly typical of late model GM vehicles. The perimeter of the panel is lined with a series of plastic upholstery clips that snap on and off. (Photo 7)

The only screw on the panel is one that is hidden behind the inside door handle trim. The trim can be removed with a small screwdriver or an offset scribe, by prying in the rectangular notch in the trim located along the rear edge. Once the trim plate has been removed, remove the single Phillips-head screw to free the top portion of the door panel. (Photo 8)

Next, the panel that contains the electrical controls can be removed from the arm rest. The panel is held in place by a tab near the front of the panel and a spring clip at the rear. Slip a small screwdriver between the panel and the upholstery and then gently lift the rear of the panel until the tab at the forward end comes free. After the panel is free, disconnect the electrical connections and the put the panel in a safe place. (Photo 9)

You can now go around the perimeter of the panel popping the plastic clips free of the door until the majority of the panel is free. Two large metal clips are  located near the rear of the arm rest, which is the major stress point on the door panel. (These clips are shown in Photo 10.) These clips can be a real pain to deal with, but the simple solution is to simply lift the panel up once the rest of the connectors are free of the door. The two clips will slid up and out of their plastic seats, allowing the door panel to come free of the door. Once the panel can be pulled out as shown above, the inside door handle cable can be released. (Photo 10)

The plastic end of the cable cover has two “wings” that hold the cable in place. To remove the cable, gently squeeze the wings together so that the cable can slide though the bracket. After the cable cover is free of the bracket, you can pull the cable portion around until the cable end will slide out of the handle through the slot in the end of the actuator. (Photo 11)

The two clips that I mentioned earlier are shown in Photo 12. The metal portion of the clip will slide free of its mounting bracket when the panel is lifted. Once the panel is free of the door, the clips can easily be removed from the door panel by depressing the tabs on each clip. Then the clip can be slipped back into the mounting bracket.

Photo 13 provides a closer view of some identical clips that I photographed on a Pontiac Bonneville. You can see the slots in the mounting bracket that hold the clips in place. The two tabs extending below the clip are the ones that you will have to depress in order to remove the clips from the door panel.

Photo 14 shows the matching bracket on the door panel that the clips fit into. (This was also photographed on the Bonneville, but it is virtually identical to the one used on the Lucerne and many other GM vehicles.) After the panel has been released from the door, the tabs on the clips can be depressed with a screwdriver through the slots in the bracket. It is possible to release the clips from the door panel bracket without sliding them out of the bracket that is mounted on the door. However, it requires you to lie on your back and work by feel with your arm wedged between the door and the door panel. I did just that the first time I ran into this type of clip, but I’ll never do it again.

The main wiring harness for the door panel can now be released. The large white handle rotates in order to release the two components of the connector. All of the electrical connections of the door panel pass through this one connector. (Photo 15)

In Photo 16, you can see the wiring harness as it comes out of the door near the front.

Photo 17 shows the opposite side of the connector that is attached to the inner surface of the door panel. You can now set the entire door panel aside in a safe place. Make sure as you set it down that you do not damage the electrical connector or get dirt into the connection.

The outside door handle is held onto the door by three 10mm hex bolts. Access to the forward bolt is through this hole in the inner skin of the door. The moisture barrier must be carefully peeled down in order to expose the access hole. Take care that you do not tear, cut or otherwise damage the moisture barrier because it is much more than just sound deadening material. As the name implies, the moisture barrier is responsible for keeping water that gets inside the door from harming the door panel and the electronic components such as the speakers. (Photo 18)

Photo 19 shows the 10mm bolt after it has been removed from the forward end of the outside door handle. The bolts at the rear of the handle are accessed through a similar hole near the rear of the door. This hole is also the hole that the vertical linkage rod passes through.

In Photo 20, you can see the rubber grommet that has been pulled out in order to access the bolts at the rear of the outside door handle. A 10mm socket on an extension can easily be inserted to reach the bolts. If you have a magnetic insert for the socket you should use it to keep the bolts from falling inside the door. At the very least, keep a magnetic pick-up tool handy in case you drop one of the bolts inside the door.

The two bolts at the rear of the handle not only secure the handle itself, but also serve to hold the lock into the door. Once they have been removed, the handle can be lifted away from the door and the lock will pull far enough out of the door for you to be able to disconnect the linkage. After the linkage rod has been disconnected from the tailpiece, the lock will come free of the door. (Photo 21)
The face cap on the Ortech locks is reusable. A small amount of gentle prying around the edge will pop the face cap off of the lock so that the plug can come out of the front of the housing. (Photo 22)
Seen from the side in Photo 23, the Ortech lock has a strap that extends the entire length of the weep-hole in the side of the lock. This is a distinguishing characteristic of the 75 groove locks; the 93 groove locks do not have this strap. It is possible to sight-read the depths of the tumblers through the weep-hole, but the lock is so easy to disassemble that I prefer to just pull the plug out of the housing if I have the lock in my hand.

An “E” clip secures the tailpiece to the lock plug. Removing the “E” clip will allow the tailpiece to slip off, but before you remove the tailpiece, mark it so that you will be able to put it back on exactly as it came off. The tailpiece is designed to fit onto the cylinder in either direction so that the hand of the lock can be changed by simply reversing the tailpiece. If you reverse the tailpiece you will be making a lot of extra work for yourself. (Photo 24)

After the tailpiece has been removed, you can see the spring-ball detent that is located at the rear of the lock housing in Photo 25. This detent provides a positive click-stop at the key pull position and also helps to prevent the lock plug from rattling inside the housing. If you just pull the plug out of the housing without regard for the detent, the ball will probably fly across the room and get lost. So, when I pull the plug out of the housing, I wrap a rag around the back of the lock to catch the ball bearing and spring.

After the face cap has been removed from the lock, you can see that the shutter assembly remains captive on the face of the lock plug. (Photo 26) Try not to disturb the shutter assembly while you are working on the lock, because replacing it can be very tedious. The process of teasing the shutter and spring back into position while snapping the cover back into place will try your patience. The only time that I can imagine it would be necessary to remove the shutter assembly would be in the process of removing a broken key, and then I’d do it only as a last resort.

With the plug removed from the lock, you can see the spring portion of the spring-ball detent. When you reassemble the lock, you will have to place the ball bearing back on top of the spring, compress the spring and then slide the plug back into place in much the same way you would load a top pin into a pin-tumbler lock. You do not want to remove the cap on the other end of the spring chamber because it is crimped into place. (Photo 27)

With the lock plug removed, you now have access to all eight tumblers. At this point the lock can be rekeyed, decoded or repaired easily. Always be sure to liberally grease the components of the lock when you reassemble it. This type of lock requires grease as a lubricant in order to function properly. If you are assembling a replacement lock, it will come with a packet of grease; be sure to use a generous amount when you assemble the lock. (Photo 28)

Part 2 of our Guide to Servicing the Buick Lucerne will cover ignition lock removal and transponder programming.           

Photos will be available soon