The gauges on my 2007 Saturn ion just stopped. I tried switching the fuses but that did not work. Does anyone have any suggestions? Thanks for any help.

 

Anything else strange happen at exactly the same time? Did anything else stop working or start acting funny?.

 

Nothing else. I noticed that when the cluster fuse is in all of the lights “brake, check engine, etc” are lit. All of them. But no gauge is working. I tried unplugging the battery and plugging back in. Nothing. I tried replacing the fuse. Did not fix. I assume it is not the cluster as all of the lights are on, but I don’t know? A bad bsm?

 

According to the wiring diagrams in the FSM, all gauges and warning lights are controlled through the Class 2 serial bus. There is no separate power source for gauges versus lights. I'm guessing the problem is either the instrument cluster or the BCM. Get/borrow a scanner that can read live data and plug it in to the OBDII port. Start the engine and see if you can read RPM, fuel quantity, water temperature, etc. If you see the correct information on the scanner, the BCM/ECM is providing data to the bus and the problem is probably the instrument cluster.

 

Thanks so much. I took it to advanced auto parts and they have codes but they were related to o2 sensors. I heard to reset the bcm/ecm you need to unhook the battery and touch the Two cables together for 15 seconds, that resets it.

if the cluster shows the turn signal and the lights—-check engine and everything else comes on—-would that mean the cluster is working or at least displaying what is being sent?

 

The Class 2 serial bus is a communication system -- only two wires -- that the BCM/ECM uses to send information to the instrument cluster and other modules (computers) in the vehicle. That the caution lights are all working is evidence that the bus is working. The caution/warning lights light. (Turn signals are 'hard wired' to the turn signal system and don't get their input through the bus.)
My suggestion to use a scanner capable of reading live data was not to read codes. Use the scanner to read the RPM, water temperature, or fuel quantity (these are the gauges that are not working). If you can see the RPM on the scanner, then the bus is carrying an RPM signal, and it means that the BCM/ECM is sending that signal. But the instrument cluster (another 'computer') is not receiving that signal, or is not sending that signal to the tachometer.
It's very possible that only part of the instrument cluster is working. On many vehicles (I don't know about Ions), the solder joints in the instrument panel circuit board can crack and cause missing or erratic indications. There are several videos on YouTube about repairing instrument panels by re-soldering the joints.

 

If your dash is lit up like a Christmas tree stays that way, it is more than likely a bad BCM.

But follow the advice given above. You want to isolate the problem before spending money on parts.

 

You hit it. It’s lit up like Christmas tree….. I take the fuse out to avoid seeing it. Could it be a relay? If not could I order the bsm and change it myself, or does this have to be done at a dealer?

 

Slow down and test first.

If it is the BCM:
It has been programmed to match all the options on your vehicle. It also stores the mileage.

You might find another in a junkyard that will run the car but not everything may work. And the mileage will be wrong. No dealer will touch it this way unless you have super documentation as to the actual mileage on the vehicle.

Usually you must purchase the blank BCM through the dealer and have the dealer program it to match your VIN. Many GM dealers will lie and say they can no longer get access to the Saturn programming files. They simply can request them from corporate. They may need an older device to do the actual programming but they exist.

Whatever you do, do not install a blank BCM into the vehicle and tow it to the dealership to save money. They will not touch it. Chevy dealers seem to be most sympathetic to Saturn owners.

Total cost probably around $700 to $900.

Which is why you want to test first.

If it ends up being the cluster, you can get a junkyard cluster but it has to be married to the BCM or it will not work. Off to the dealer.

This is exactly why you want to determine which part is defective.

 

Very good and logical advise!!! Thanks. One question though. Either fix requires a dealer so would it make sense and go ahead and take it to a dealer therefore bypassing the testing?