Honda CR-V Battery Drain

Originally Posted by ondarvr
The CRV battery going dead is a common thread on Honda forums. The battery is small, and the charging system has two stages, one where it supplies 14.2 v and another at about 12.5. The higher charging rate kicks in if it detects a higher load, like turning on several accessories. What happens is the battery is frequently left under charged. This to get that last .002 mpg for advertising and EPA. It sacrifices the already too small battery for an ever so slight mpg improvement. Turning on the air conditioning triggers the higher voltage, so people just leave it on. When failing these batteries can check out good at the dealer because of how they test them, so people come back several times before it finally tests bad. Then they sell you another cheap small stock battery that will fail again. Another problem, which I had on two recent Honda purchases, a civic and a CRV. Is they sit on the lot and the battery goes dead, they quickly charge it before the sale, but the damage has already been done and its useful life has been shortened. In my case, the batteries in both cars were dead, but the dealer put in new larger Die Hard 35s instead of the smaller stock batteries.
Great post in my opinion ^^^^^^^^^^^^^^ Hit all the points extremely well... 1) batteries sitting in the sales lot and being damaged permanently... 2) under charging of batteries by the alternator and ecm attempting to save fuel 3) use of smaller group 51r battery 4) using much better group 35 battery instead
Aunts 2018 CRV got a battery this week.. it was in warranty by 9 days.

It was blue foaming at the pos. terminal. resistance was over 40 and cca was reading 150.
It was also self-discharging as I watched.

Threw it on the 10 amp charger for 30min.. and it barely started.(had a jump box for backup)

And miracle.. they replaced the battery and erased all the codes caused by the dead battery
the battery started out at 2.2volts. I was expecting to have to jumper it to get my smart charger to kick in..
but apparently thats high enough.

Of course the new battery is out of warranty in 8 days