Rep Power: 0

I purchased a used 04 civic hybrid a year ago. Everything was fine for the first month or so, then the IMA and check engine light came on. I replaced the 12 volt battery; however, winter was murder on the hybrid battery charging as it should. I reserved myself to replacing it but when warmer temps came, it started to work great. I was getting 42-47 mpg and no lights on the dash. Fast forward to the beginning of June. The car has started to develop a dead 12 volt battery every morning when I set out for work. I jump it and the IMA charges fine. The battery does not die the 12 hours I am at work, only at home. There is no parasitic draw on the battery. Yesterday I charged the battery for 12 hours on a 2 amp trickle charge and this evening it was dead again. Also, I replaced the front brake pads a couple weeks ago and now the IMA, check engine, brake and ABS lights are on. IMA is still charging fine. I have not had the codes read yet because I wanted to have the codes read, erased and read new codes and wasn’t sure if the auto parts store can clear the codes. My reader will not.

 
Rep Power: 244

How did you determine the battery was dead? Volt meter? If you disconnect the negative battery terminal it will reset the ECU.

 
Rep Power: 0

Turned the key on and entire dash dead. Not even a click to try and start. Today I replaced the cheesy battery terminals with new ones, cut back and stripped wires and the car started. IMA, brake and ABS light stayed off the whole 45 minute drive to work. Left on break a little while ago and the lights are back on. I check every under dash fuse and engine bay fuses and none are bad. The brake and ABS light didn’t come on until I changed the front brake pads. Simple job, fluid is good. IMA light had been off for month with 47 mpg.

 
Rep Power: 367

another case that it's not just parts...
wiring, connectors also get bad, especially after decades...
glad you found your problem and that was not the wiring (way harder to find those than connectors that are more accessible than stripped insulation somewhere in the dozens of miles of wires in a car...)
people just don't understand when we say to check wiring/connectors...

 
Rep Power: 0

Any thoughts as to why the IMS, brake and ABS are still coming in. The charge/ assist function is working fine, the brakes are good and the lights generally do not immediately come back on once a new start cycle is initiated; however, moments later, BAM, there they are. Putting brake pads in the front should not have affected any portion of the ABS system should it? I did have to add some antifreeze the other day which I thought was strange. Car always runs one bar below 50% on the temp guage.

 
Rep Power: 0

Start the car and measure the 12v battery voltage. It should be 13 volts or over. Sometimes on the hybrid models the battery does not charge properly, especially shortly after starting. You may see a battery voltage of 11 volts even though the engine is running. That will cause a bunch of systems to fail, and lights will come on for them - EPS (power steering) will go on and off as you turn the wheel, ABS will be on, and I think airbag too.


If that's fine, then I'm afraid you need to read the codes. Spend $6 on a bluetooth code reader from ebay and pair it with a phone or laptop (these cars don't use CANbus, so you need an ELM327 that can do k-line). That will tell you whats wrong.