Question on a 2006 Honda Civic Hybrid

My wife and I are the original owners of a Honda Civic Hybrig. It has 138,000 miles on it. It is in pretty good condition. Recently we have been having some problems with it.

The Check Engine Light & IMA light has been coming on. We have noticed at times that on a Monday, after sitting the whole weekend, that it does have a “hard start” that Monday. It is obvious that it takes a second for the car to start.

We have recently spent some money on the car for the following:

Transmission Fluid Flush
Tires Rotate & Rebalance (routinely done)
New Headlights (old ones were burned out)
Oil Change & filters (routinely done)
Valve adjustments
Total of all 8 spark plugs replaced in hybrid
wiper blades replaces (routinely done)
auxiliary battery under the hood replaced a year ago (the one that starts the system, and tied to the ignition)

This was done care of a mechanic who knows Honda hybrids.

A day after this was done we now have a Check Engine Light & IMA light on. When I took it back to the same mechanic and asked him what’s up, he tells me that the diagnostic codes he is getting indicate:

  1. The Hybrid charging system is malfunctioning
  2. The Hybrid battery cells (under the back seat of the car) have deteriorated to the point that the car’s computer is now noticing a difference between the cells, and therefore not functioning.

The question of my wife and I are the following:

  1. Does this sound fishy and the mechanic’s trying to cover his tracks?
  2. We understand that the hybrid batteries can go after about 8-10 years. What is the actual design life of the hybrid batteries?
  3. How quick do we have to respond and fix this as far as car performance (we understand that we have to worry about emissions testing, and we still have one year before retesting)?

Comments are appreciated. Please advise. We are in the process of getting several price quotes for this, and it is in the couple of thousands.

I thought the warranty was 10years, but I don’t know the mileage restrictions.

@Rahul4977‌

Please post all of the trouble codes, engine and IMA

First of all, the hybrid control module should have the latest software

Second of all, if the 12V underhood battery is questionable in ANY way, replace it.

If the 12V battery is bad, it can cause P1435, which will cause the check engine light and the IMA light to come on

But yes, your car is at the age where the hybrid battery pack typically starts to fail . . . on a Civic Hybrid

We have lots of these in our fleet, and none of the hybrid batteries last 10 years. Most conk out a few years before that