Exquisite Goods

This started out innocently enough as a way to spruce up the original steering wheel which had become quite worn and shiny after six years and 100,000 miles (’97 740iL). The wheel looks better than some others I’ve seen, but after successfully adding heated seats to all four positions, I thought, “Why not make it a heated steering wheel?” and finish my own Cold Weather Package (sans headlight washers). I decided to document the procedure in case anyone else is thinking about replacing or upgrading their own steering wheel.

For background, I first explored the idea of having a leather shop replace the leather on the steering wheel. After getting several quotes in the mid $300 range, all with caveats that it wouldn’t look quite the same as the original, I decided to abandon that idea and just get a new wheel from BMW.

The steering wheels for the E38 and E39 models appear to be the same, but you have to be careful about production dates for the vehicles. You may also have to order a new slip ring, as I did, if you want to add the heating option. In my case, the car has a production date of 06/96 and a non-heated steering, so it required a new slip ring in order to accomodate a heated wheel (approximately $490 from the dealer). That also meant replacing the right button pod to have the heating button in place of the air recirculation button. Because the left button bod was somewhat scratched and squishy (not a very technical description, but if your buttons have some age you know what I mean), I replaced it with a new one as well (approximate cost was $88 for each side).

IMPORTANT: Before working on your steering wheel, disconnect the car battery (negative terminal in the trunk) and avoid and static discharge. The steering wheel contains the airbag and you could be injured (or maybe even killed, so I’m told) if it discharges in your face. Exercise caution when handling the airbag assembly and, when setting it aside, lay it face up without anything on top of it in order to avoid launching anything at you should you accidentally set it off.

BTW, when I started this, I didn’t even know what a slip ring was and I’ve never removed a steering wheel before. For those of you like me, the slip ring is the round device on the back of the steering wheel that enables the electrical connections between the car and the steering buttons and airbag while the wheel turns. It’s basically a ribbon cable wound up into a spring-loaded coil with a connector coming out of the back. The photo below shows what I’m talking about. It’s a picture of the back of my original steering wheel. The ribbon cable has been pulled out slightly so that you can see how it works.

Now you know how your steering wheel buttons connect to the rest of your car!

The first step is to remove the airbag, which is attached to the steering wheel with two T30 torx screws on the back. The photo below is a view of the rear side of the steering wheel showing the hole for one of the screws.

Once the two torx screws are unfastened, the airbag assembly can be lifted away from the steering wheel as depicted in the next photo. The airbag assembly is connected to the steering wheel by a orange connector for the airbag itself, a separate six-pin connector for the button controls and a spade connector for ground. The orange connector in the center of the airbag just pops off. I used a small flat-blade screwdriver wedged underneath it to pop it off, but you can also use your fingers. BE CAREFUL to avoid static electricity while handling the airbag assembly.

This is a view of the back of the airbag assembly. Note that you don’t want to leave it in this position. Turn it over when not working on it to eliminate the danger of having it launch itself should it accidentally go off. The left and right button pods are connected to each other by the wiring harness that can be seen circling over the top, and to the airbag housing by two torx screws on each side. The new button pods come complete with their own wiring harness and replacement plastic guides.

The next step is to install the new button pods on the airbag assembly. Remove the two torx bolts as shown to release the button pod. You can leave the wiring connectors in place since the new buttons include a new wiring harness.

This photo shows the old right-side button pod with the air recirculation button and the new button pod with the heating button. Attach the new button pods to the airbag assembly using the torx screws, and route the new wiring harness over the top of the circular part of the airbag frame as the original did.

This is what the steering wheel looks like with the airbag assembly removed. The wires are part of the slip ring on the back of the steering wheel, so you don’t have to remove them.

The next step is to remove the center bolt using a 16mm socket wrench. You have to use a bit of force to loosen the bolt, so its handy to have someone hold the steering wheel tight while you work. By the way, you don’t have to have the steering wheel perfectly centered before you start since, as I’ll explain below, the wheel and the spline onto which it mounts are both marked.

A closeup view of the center of the steering wheel with the bolt removed. If you’ll look at the bottom of the center area, you’ll see a small white line and a corresponding notch engraved into the wheel. These are the alignment markings you’ll use to confirm proper placement of the steering wheel when reinstalling it. The white plastic piece with the torx bolt going into it is part of the slip ring mechanism. The rest is just a white plastic cover to keep the wiring behind it.

The connector coming out of the slip ring is separated into two connectors (not shown), an orange one for the airbag and a white/black one for the button controls. These two connectors attach within the steering column to mating receptacles, and they’re somewhat difficult to reach. To do so, detach the lower steering column cover by pressing in around the front sides, next to the turn-signal and wiper stalks. The cover can be pushed down slightly as shown, which is enough to get your hand inside to disconnect the two connectors. Before you do that, be sure to make a visual note of their location and the orientation of the two connectors. Both connectors are keyed, so you can’t put them back in the wrong way.

Once the old connectors are removed, bring the new steering wheel close to the steering column, but don’t put it on just yet. Carefully extend the wires from the back of the new slip ring into the steering column and connect the two connectors. You may have to slide some of the ribbon cable out of the slip ring in order to have enough slack to reach the connections. Don’t worry about that as its very easy to slide the ribbon cable back into the slip ring. Just don’t crimp or cut the ribbon cable. Again, it helps to have someone else hold the steering wheel while you make the connections.

Once the connections are in place and the ribbon cable is back into the slip ring, slide the new steering wheel onto the steering column, paying attention to line up the white line on the column with the notch in the steering wheel as previously described. Now is a good time to snap the lower plastic housing of the steering column back into place.

Re-insert the 16mm bolt into the center of the steering wheel and tighten it strongly. If you have a torque wrench, I believe the specification calls for 70NM, but I’m not quite sure. I probably over-tightened it, but I didn’t want it coming loose for obvious reasons. Again, having someone hold the wheel while you do this is useful. I’m not sure how strong the steering wheel lock it, but I was afraid it might break without a countering force.

Bring the airbag assembly with the new buttons installed over to the steering wheel. Again, be careful to avoid any static electricity while you’re handling the airbag. Try to keep your face away from the front of it, too, just in case!

Attach the three connectors in the steering wheel to the airbag assembly: the orange one to the center of the airbag housing, the ground spade, and the remaining 6-pin connector for the buttons. Again, all connectors are keyed so you can’t make a mistake. Just don’t forget to connect the orange one for the airbag or the onboard computer will throw an error and display the airbag light in the dashboard when you reconnect the battery.

Once the airbag connections are back in place, lay the airbag assembly back into the steering wheel and revel in the fact that you’re nearly finished. All that remains is to tighten the two torx bolts on the back of the steering wheel and reconnect the battery.

When you’re done, your new heated steering wheel will look like the photo below.

There is one caveat, depending on the production year of your vehicle. In my case, the fusebox in the engine compartment doesn’t have wiring for the heated steering wheel (fuse # 36, 10A), so I’ll have to either tap into another power source in the steering column or run a wire. That’s another project for another day though so, for the time being, the heating button doesn’t actually do anything yet. However, the new leather wheel and buttons by themselves are enough to take years off the “feel” of the entire car. Since the steering wheel is the one component you use more than anything else, I think its worth it.

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