No lights on dash board, motor won't stop. "combination meter"

We have owned our Prius since 2011, with no problems, other than the need to replace the 12 volt battery this past fall. Recently the dashboard display was totally dark. Nothing showed- altho the car would run. But then- it wouldn’t stop. We called the local dealer who ran thru several options- and finally the car turned off after holding the power button for several seconds. We took it in- and were told it was the KAAR security system, which should be removed. To the tune of $500 we had that done. The next morning, the exact same problem happened. We learned there is a warranty on this issue and the problem has been known for some time- affecting a number of years of the Prius. Our dealer seems determined NOT to follow Toyota guidelines for dealing with the issue- and in fact didn’t even bother as far as we can tell…to check Toyota specs and warnings. The warranty has recently been extended for 9 years from 1st use (or Sept 13) which ever is the longest. Is this an issue that anyone else has dealt with, and how can we ensure the dealer handles this with integrity.

Talk to the dealer on more time and give them a chance to make it right, tell them the info you have here and ask for a refund. If they do not cooperate quickly, look in your owners manual to find information for the zone office. Give them a call and tell them the situation.
You will get action from the zone office.

I am not familiar with the warranty extension on the combination meter, is that what you were given an estimate for? What year is your vehicle?

There is warranty enhancement program for the inverter/Intelligent Power Module. An IPM failure will illuminate the check engine and hybrid system warning lights but you didn’t mention that any warning lights are on.

When experiencing intermittent electronic problems it is advisable to remove add-on devices that may interfere with the vehicles systems, you have the right to do that yourself or by the installer of the alarm.

It sounds like you have not returned to the dealer since the alarm was removed to demonstrate the problem has continued, you should leave the vehicle at the dealer so they can complete the diagnoses.

the dealer claimed the security system was the problem and he took care of removing that. The problem continued. …the dashboard goes completely dark- no warning lights of any kind. We did go back to the dealer who declared ignorance, then came up with the Toyota extended warranty…which we later found online and printed out. The car is now back at the dealer to have the combination meter (I think that is the term!) replaced at Toyota’s expense, and also Toyota is supposed to pay the earlier expense that was not needed. I appreciate your response and knowledge!

Your Prius must be a 2009 or older, the only year reference you gave was the purchase year. There is a warranty extension on the combination meter, 9 year from the date of first use;

Warranty Enhancement – ZTV
2004 to Certain 2009 Model Year Prius Vehicles
Extension of Warranty Coverage for Combination Meter

Toyota is offering a Warranty Coverage Extension for the Combination Meter for 9 years with no
mileage limitation from the date of first use or before September 30, 2013 whichever is longer
for the condition described above. If this condition exists, the dealer will replace the Combination
Meter under the terms of this warranty enhancement program.
Please note that damage incurred from abuse, an accident, vandalism or non-warrantable causes
are not covered by the New Vehicle Limited Warranty or this Warranty Extension.

Just curious, was this alarm KAAR system installed by the dealership before you purchased the car, or did you have it installed on our own, by someone besides the dealership? The reason I’m asking is b/c if the dealership thought the alarm was the cause of the problem, they might complain about doing any further warranty work on gadgets the alarm system might have damaged.