I have a 2001 SLS that I was going to upgrade to XM radio, but that project is now on hold (I haven't even bought the radio yet) because the car is suddenly showing signs of ill health.
Here are the symptoms which have all started in the past couple of days:
1. The gauge cluster went dead while driving. Upon a restart, everything came back except the fuel gauge and temperature gauge which remain dead.
2. The outdoor temperature indicator yesterday provided me with readings of -40 degrees F and 163 degrees F. My average miles per gallon were consistently reported as 0.2 mpg even upon resetting (and I wasn't leadfooting!)
3. A "SERVICE IDLE CONTROL" alert message appeared. I thought that the idle might be slightly faster than normal, but it wasn't fast enough that I could be sure.
4. An "ENGINE COOLANT HOT" alert message appeared. I don't have a working temperature gauge any more, so I can only rely on my senses. I popped the hood, and nothing seeemed overly hot that I could perceive.
I am wondering how many of these problems are related to each other. It's strange that so many things could go wrong at once. Is there a computer problem here, or is it just a faulty gauge cluster combined with some other problems occurring coincidentally?
I found a service bulletin (a portion is attached) that explains at least #1 and #2 above -- it's a software glitch in the instrument panel that affects some 2001 Sevilles and Devilles. I will have to replace the instrument panel. If anyone has any pointers on replacing the gauge cluster, I would appreciate hearing from you.
Maybe #3 and #4 are also due to this glitch. I am hoping so!
the cost of having your cluster repaired after you have removed it is $365
removing the cluster itself is a doddle,im in the process of packaging mine up and sending it to instrumentcluster.com for repair,its a very common fault.
I believe to fix my problem I just need to upgrade to a used 2002 cluster (the software issue that my cluster is plagued by apparently was resolved after '01). So I am going to buy one online rather than having my old cluster repaired.
However, there is a possibility that there will be an odometer discrepancy with this approach.
However, there is a possibility that there will be an odometer discrepancy with this approach.
Mileage is stored in the cluster - you will need to have it reset. Call a dealer and find out the particulars before you swap out the cluster. Read here:
If the replacement turns out not to be plug and play, I think I will just go with an amended mileage statement with the title. I am not planning to sell the car any time soon.
Well, here's an odd twist. The car battery suddenly died today. I believe it was the original battery, so I am not too surprised that it expired. After getting it replaced, voila -- the dead fuel and temperature gauges immediately came back to life! Too bad this happened only after completing the order on a replacement gauge cluster!
I wonder if reduced battery voltage could have somehow triggered the original gauge failure.
We'll see how long the old cluster remains working. I am not planning swap it out unless it fails again.
Gauges, etc. 
Mileage is stored in the cluster - you will need to have it reset. Call a dealer and find out the particulars before you swap out the cluster. Read here:
