TeamD Adventures

It’s a nice feeling, fixing your own car. First, you’re saving money; and when you hear your co-workers mourning the cost of their last service, you feel even better. But it’s not just the money — repairing machinery makes you feel… wise… and capable; you feel talented. It’s a nice boost to the ego.

Ah, but there’s another side to that coin, you know. If you get in there, and you make a mistake, you feel stupid.  In fact, you feel stupid on two levels: one, you should have known not to press on that thing that you pressed on (substitute “pry”, or “trim”, or “pull”, or “cut” until the shoe fits), and two, you should have known a priori that this particular repair was beyond you.  This repair should have been given to the folks with the special tools and secret books: the techs at the dealer.

Apropos of nothing, have I told you about my modern German techno-car? Have I described its multiplexed communications channel for control of accessories? Did I already mention the MOST-bus that connects the “automotive media devices”?  If I’ve not raved about it yet, you should know that the MOST-bus covers about 4 of the 7 OSI layers. It’s slightly intimidating, to tell the truth.

Look: all I want to do is play my iPod through the stereo. How hard can that be?

Well, there are two answers to that. If you just want to control the tune that’s playing with the iPod’s touch wheel, and you’re satisfied with a few hours of music on a iPod charge, it’s simple. Plug in a stereo mini cable and you’re done.

But if you want to charge the iPod while it’s in the car, or change the track or playlist with the radio controls, or maybe see the track or artist name on the radio’s character display…  then you need to interface with the MOST-bus. Thankfully, BMW has anticipated your need! And they’ve produced an accessory MOST-interface box! And you can buy this, yes, from a dealer, as a kit!  It comes with instructions!

Mmmm… yes… it comes with a little booklet bound in cool, white, semi-glossy paper reminiscent of the owner’s manual. The booklet is the “end user” documentation:

How to play a tune. How to change volume. How to plug in your iPod.

The kit does not come with installation instructions… of any sort. That omission sends a pretty clear message:

The owner is not expected to install this.

To be fair, there’s a portion of the installation that most people, of whatever skill level, will be completely unable to do: reprogramming the car’s command and control system to recognize the new device on the MOST-bus. That takes special electronic equipment only found at BMW dealers.

But you could, theoretically, install the hardware and wiring, and simply take the car in for reprogramming
– if you were mechanically inclined
– if you had past experience in automobile dealership service departments installing accessories
– if you found the real installation instructions somewhere.

I am, I do, and I did.

So I thought I’d “save” the hour’s labor charge that the dealership wanted to install the hardware & wiring. I gathered my tools and went to work. Draw now the curtains in your imagination, and race forward in time to that point where I admitted defeat and began backing out. Never mind the nature of the insurmountable obstacle that turned me back; what’s important is the next bit. After the trim was all back on, and the battery reconnected, I started the car to verify that it still operated.

And a new warning light came on, one I’d never seen lit before. It trumpeted that the 4×4 system was inoperative, and – more than that – it screamed that some fumblefingers had been touching things he oughtn’t.  Key off, battery disconnected, trim back off, double-check all connections, reassemble:  4×4 warning light shining still, like the sun at midday.

Ohhh, the angst, the agony, the self-torture and self-loathing I felt then. “Save” money? Hah! I’d be paying for that hubris, in spades! I dreaded the report I must give to the service advisor: “I tried to do something myself, and I think I broke something somehow.”  My confidence was shattered. My spouse was kind but I thought I saw, even there, a flicker of disdain for my weak skills and my smug arrogance.  Twice times stupid — that’s me.

The car came back from the dealer this week, with the MOST-interface installed and the systems reprogrammed and the 4×4 warning light dark. The iPod works great.  Want to know what caused the warning light?

Bad steering angle sensor.

It’s in the column, nowhere near where I was working; couldn’t have been damaged by anything I touched. It was a mere coincidence that it failed while I was tearing apart the dash.   Just. A. Coincidence.