2012 Honda Civic Hybrid. My car recently started throwing error codes along with the dash "Check IMA System" and "Check Brake System" messages. They all pointed to the Inverter and through this forum I learned a lot about my hybrid system. I ended up going to Bumblebee Batteries and replacing the whole MPI unit with the inverter and dc/dc. After installing it, this cleared 7 out of 8 error codes and left me with one last code of P0A27 and I am stumped. Bumblebee says it's the battery. Honda says it's still the inverter. I've checked any fuses labeled anything about the IMA. I've cleaned off terminals and connectors. I put in a brand new 12v.
What really confuses me is that if I clear the code, then start the car, the code stays off and the car runs amazing. Battery charges, engine stops when idle, I can cruise on the freeway. If I turn it off and turn it back on, the error code pops back up. If I try to drive it with the code on, the car can't get above 10 MPH and drives in limp mode.
Since it is a dc to dc converter, you need to take a look at the output waveform. It is usually some kind of square waveform Also they usually have some kind of series inductor for filtering the ac component. You need a mechanic who has an oscilloscope with an isolated dc voltage sensor which is used for the measurement. The multimeter will not show you the whole story.
