Hi,

I purchased an 03 HCH w/ 130,000 miles about a year ago and no issues at first with the IMA battery system. A few months ago the IMA light would come on and stay on for maybe a day or two then go off for a few weeks at a time. About a month ago the light came on as well as the CEL light and have stayed on. Yesterday morning I started my car and noticed that the red 12v light was on but went off when I had the RPM's above 1500 and the charge/assist was not working with the battery showing no bars. I did some searching and saw a couple threads that mentioned removing the negative battery cable for 30sec and then putting it back on and starting the car back up. That seemed to work as both the IMA and CEL lights went out and the battery showed 4 bars on the green charge indicator. I let it run and charge for about 20 min. Then this morning I started the car and drove to work with both the charge/assist working fine but the IMA and CEL lights came back on. I've seen a few threads about grid chargers and was wondering if anyone thinks that that may be able to fix my issues. Any advice is greatly appreciated. Thanks!

 

Why did the IMA and check engine lights come on?

 

Not sure. I haven't had the codes read yet. I'm going to swing by autozone after work to have them retrieve them for me. Also, the 12v battery in this car is from 09'. Could this be part of the issue?

Thanks

 

A healthy 12V is critical. When you're there, have Autozone test it AFTER reading codes. If you have OReilly in your area, they are a better choice.

All descriptions suggest that your IMA battery has failed, but the codes will tell you for certain.

 

OK. I will go to oreilly instead and have them read the codes and then test the 12v battery. When I unhooked the negative battery cable for 30 sec and then reset it that way I only did that once. I read somewhere that maybe I should have done that 3 times in a row?
Thanks!

 

That's a common recommendation of mine to maximize the charge in the battery. It doesn't fix a bad battery, but it might work long enough to get you through emissions.

Again, all symptoms are pointing to a bad battery, but you need to check the codes.

 

Ok. Do you think that I should redo the process but 3 times instead of 1? I'm still at work and will head to have the codes looked at right after. I'll also have them test the 12v battery. Where I live we don't have emissions testing so that is not a concern. Once I post the codes based on those would you be able to tell if a grid charge might prolong the life of the battery?

 

No. Disconnecting the 12V clears the codes. You need to get the codes.

Reading the codes is important to understand what you're dealing with.

I understand you want to know the answer to the question, but the more important question that must be answered is, "what is wrong with my car?"

 

JUST got back from oreillys. They said my 12v battery was good just that the volts are a little low. Codes they pulled up according to the printout are p1600, p1449, also on a separate page Dtc p1431, 1432, 1433. Thanks again for your help.

 

Normally, P1449 indicates severe battery deterioration, but you have two other codes indicating temperature issues + P1433 battery deterioration.

Frankly, I have personally never seen a battery that gives me as much concern as that combination of codes. I would conclude that your battery is a **** show on that basis alone.

The more codes there are, the more I suspect the 12V. "volts are a little low" makes me very concerned, i.e., I think that's a load of bullsh1t.

If I were you, I would replace the 12V. It's a relatively small expense, and it is very likely to need to be replaced soon regardless. Additionally, I would check the 12V grounding cable for continuity as well as the other grounds (transmission to unibody and engine to unibody) to make absolutely certain they are in good shape. All are prone to corrosion and deterioration, which can result in multiple faults.

After replacing the 12V, the codes will be cleared. Drive the car and get codes checked as soon as you get IMA or CEL.

Reassess at that time.