2006-2008 Civic Hybrid Battery Fix Worsens Performance & Mileage
In July 2010 Honda issued new software for the 2006 through 2008 Civic Hybrid battery charging system to address complaints of diminished fuel economy and loss of power. Honda's letter to owners said the software was to prevent the integrated motor assist (IMA) battery from deteriorating and eventually fail.
The new software limits the amount of time the electric motor kicks in--prolonging batterylife but reducing the amount of assist the IMA electric-drive system provides the car's tiny four-cylinder gasoline engine.
Honda undoubtedly took this action in part to less the number of batteries it would have to pay to replace under its eight year factory battery warranty.
The problem is that after the software was installed, owners experienced reduced gas mileage (10 mpg or more) and less power. Post-software upgrade, owners said their cars were a "gutless wonder," having "less assist," the battery would not take as high a charge, at 4 bars the assist is unpredictable, and the assist will stop at critical times like when entering a freeway on-ramp.
Civic owners have many posted complaints about the impact of the software change on Internet forums, including www.greenhybrid.com, www.hybridcars.com, www.autoblog.com, and ConsumerReports.org (CR's car blog).
On behalf of a Civic hybrid owner, I have sent Honda notice that its failure to disclose the true impact of the software change violated various California consumer protection laws.
