2010 Prius - Only half cluster lights up and other issues

if you are going to diy, i would buy a cheap volt meter.

check the 12v after it has been off a few hours. if it is good, you probably need a new combination meter. (the half lit dashboard)
but that can be caused by a low 12v.
never hurts to change the fob battery, but i don't think that's the problem. you can use your new volt meter to check the old and new fob battery voltages as well. a new one should be 3.3 volts.

also, a trickle charger, jump pack and small 12v compressor are good investments.

 

probably need a new battery. measure it in the morning before turning anything on.

 

also, it may go way down when you put a load on it. have auto zone test it for free, or someone, they have a machine to do it right. florida is hard on batteries.

 

That seems fishy.

Not sure, but I seem to recall a low fob battery will trigger a warning on the dash?

A little hard to judge. Considering you charged all night just a day back, that might be a borderline battery with still a bit of "surface charge" (battery tends to read artificially high right after charging). Maybe monitor daily first thing in the morning, if it's stable at 12.5 that's so-so. If it continues to drop then better get it assessed with digital load tester (most retailers will have) and consider replacement.

I still think it odd that half your dash is out: some electrical disconnect??

 

12.5 volts at rest is not bad. Something like Solar BA5 (or BA7, more readily available now?) will give a better assesment, if you want to drop $70~ for a diagnostic tool. It assesses voltage too, but primarily is used to measure Cold Cranking Amps (or Cranking Amps, or a few others). While not technically needed on the Prius, the CCA is still a valuable barometer of the battery's health.

Most automotive retailers selling batteries would have a pro-level version of this sort of tester.

 

Normal resting battery should be 12.6 volts.

 

Have you checked the fuse?

 

Check the 10amp fuse and the 7.5amp fuse in the engine bay. It’s possible it could be a relay as well. Those are what’s giving power to the combination meter assembly.

 

I find it interesting that a weakening battery could cause half the dash board lights to go dark. To test the battery theory could I just hook a battery charger up to the under hood charging points? Wouldn't the charger provide enough juice to light the second half of the dash board.

 

Just occurs to me: half of that display is actually projected image from below. People have tossed a business card in there and been flummoxed to see the display half-gone. Could it be that??

 

You’ve got the descriptive words flowing today.

 

Half the display comes and goes. That doesn't sound like a sheet of paper sliding around. However, putting a sheet of paper over the mirror is one way to get a Prius owner's adrenaline flowing.

A weak fob battery displays a warning message on the MID. Ignore it long enough and you'll be pressing the start button with the fob.

 

any update?