SUB-BATTERY MALFUNCTION INTEGRATED CAPACITOR (INTEGRATION CONTROL SUPPLY)

Got a message while driving that SUB-BATTERY SYSTEM MALFUNCTION back in April. Was able to clear the message by restarting the car. When the error popped up I lost the ability to use radar cruise control. Happened again a couple of weeks ago and my dealer called me while I was driving and set up an appointment.

Here is a picture of the error message.

Took it into the dealer this last week and here is a summary of the service which was covered under warranty.



They wanted to know if I had installed any aftermarket accessories which I haven't. Still a mystery as to what triggered the INTEGRATED CAPACITOR (INTEGRATION CONTROL SUPPLY) part to fail.

Interested to hear if anyone else has run into this issue.

 

Not completely. Had a second sub-battery system failure most likely due to a different cause. My best guess to what caused it the first time is a short I made by accident in the 12V auxilliary power port while trying to check the voltage with a multimeter. Wasn't careful enough and accidentally let one of the probes of the multimeter touch both the tip and the side at the same time.

The second time my best guess to the cause was running a readiness test on the car while the car was in 'Room Mode'. Trying to clear a error code on the digital rear view mirror and subsequently ran a readiness test to see if it was cleared but the car was not in 'Ready' mode. The result was that the second time it discharged supply control capacitors beyond a point that could be recovered.

My understanding is that it is kind of a grey area which warranty covers it. Looking at the service document I don't see any indication as tto what warranty covers it. I saw a video while waiting for my car the second time from The Car Care Nut about how Toyota sends components to an electronics specialist to look for the cause. Without me telling them they indicated in conversations that the first failure was due to a short and the second failure was due to excessive drain.

I am guessing if you have a part that is failing due to a known design flaw or some other issue due to some other oversight by Toyota and you are out of the 3 year bumper to bumper the same part can be covered by Powertrain (5 year) or the hybrid components (8 year) warranties. I got this impression from talking to my advisor at the Toyota dealer. The first time they covered it completely. The second time they gave me a loaner car and I bought the part from Impex for ~$325 plus import tax and shipping so probably more like ~$400 versus the $2k they quoted if I bought it from them. They comped the labor for the replacement the second time.

One other thing I learned in the process was that Toyota America can comp the part for goodwill and it looks like this is an option they reserve for loyal customers that have purchased many of their cars. Toyota America did not decide they wanted to comp the part for me this time. This is my only Toyota.