Alternator?

Old Nov 4, 2024 | 02:38 PM
  #1  
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Default Alternator?

Hello all,
My 05 Civ Hybrid had the original battery, 220K miles. It went bad and wouldn't retain charge. My neighbor actually works on those hybrids as a side gig and he replaced the bad cells (18 out of 20 apparently) and rebalanced them.
I reinstalled it in the car, but the problem is worse now. IMA light is constant, red battery light is on, hybrid battery never shows any progress in charging.
I tried resetting by removing the IMA, the ECU, and the backup fuse and disconnecting negative 12V battery terminal for 10 minutes. No joy.
We put all that back and started the car, neighbor then removed the negative 12V terminal while the car was running and the car showed signs of low current and then died.
Neighbor believes the alternator needs replacing.
Does anyone here know whether
1. these cars do indeed have an alternator?
2. whether that might potentially resolve the problem?
 
Old Nov 4, 2024 | 08:00 PM
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Default Re: Alternator?

Going to be blunt.

Based on the information provided, your neighbor is incompetent with regards to your vehicle even if he has experience/competence with other models.

He likely did not do a quality battery build.

No Civic hybrid has ever had an alternator installed by the factory.

What codes are the car reporting?

 
Old Nov 5, 2024 | 05:19 AM
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Default Re: Alternator?

Thank you.
The only code was about the IMA - O'Reilly's scanner says P1600. That was with the old battery installed. I have not gone back for codes since the new battery was installed. Should I?
 
Old Nov 5, 2024 | 08:38 AM
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Default Re: Alternator?

Originally Posted by 05civic_hybrid
Thank you.
The only code was about the IMA - O'Reilly's scanner says P1600. That was with the old battery installed. I have not gone back for codes since the new battery was installed. Should I?
P1600 is non-code, i.e., it's the code that says, "there something wrong with the IMA system." There MUST be other codes. If your neighbor didn't know this, he has ZERO competence with Honda Hybrids. He should not be allowed to touch your vehicle again.

Did you blink the codes?

https://99mpg.com/mikestips/readingtheblinkcod/

While the codes won't apply to your vehicle 100%, the blink method does. What codes do the CEL and IMA light yield in terms of two digit codes? I can look them up in the service manual.

 
Old Nov 5, 2024 | 09:28 AM
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Default Re: Alternator?

Many thanks for your replies.
When you suggest in the graphic to short those two pins, the idea is that I would insert one end of some metal wire into one of the pinholes and the other end into the other one, and then plug in the OBDII code reader?

Is such a reader available at, say, O'Reillys? Are those readers sufficient?
 
Old Nov 5, 2024 | 09:38 AM
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Default Re: Alternator?

Please read the webpage. If you actually can't figure it out after reading it, please ask a pertinent question.
 
Old Nov 5, 2024 | 03:55 PM
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Default Re: Alternator?

Thank you.
The IMA light gives the blink codes, looks like. Results are: 15 and 73

I can see that 73 for a 2005 model is battery cell overheating, although maybe I am misunderstanding because that doesn't match the "P1600" that O'Reilly's machine indicated?
I could not find 15 however, and would appreciate any other ideas. Thanks again!
 

Last edited by 05civic_hybrid; Nov 5, 2024 at 03:58 PM.
Old Nov 5, 2024 | 04:09 PM
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Default Re: Alternator?

Again, P1600 is just "you have a fault somewhere in the IMA system." It is not diagnostically meaningful. Oreilly switched from Bosch to Innova code readers a few years back. IMHO, they are not reliable.

15 is P0562 MCM Power Source Circuit Unexpected voltage. Please check the #9 BACK UP 10A fuse in the under-hood fuse/relay box.

73 is indeed P1432 Battery Cell Overheating.

This is related to the PTC circuit I mentioned above. Please see: https://electricvehicleforums.com/fo...4-hch-i-32359/

This further supports my assertion that your neighbor did a bad battery build.

Any Check Engine Light blinks?
 

Last edited by S Keith; Nov 5, 2024 at 04:15 PM.
Old Nov 5, 2024 | 06:56 PM
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Default Re: Alternator?

Check Engine blinks 41 and 69

And the #9 10A fuse under hood... I had checked that fuse specifically a few days ago during earlier troubleshooting efforts. Now that you mentioned it, I just checked it again and it is blown!

I will read the linked thread now, thank you. Any other ideas are much appreciated.
 
Old Nov 5, 2024 | 07:13 PM
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Default Re: Alternator?

Also, I just read your Disable the IMA thread and answers...
My own main concern has not been, say, a loss of 10-15 mpg fuel efficiency, but rather that since the original battery went bad, the performance of the car is total garbage.
It's a manual transmission (should have mentioned that earlier, apologies) and even in 2nd or 3rd gear it doesn't get above 20mph if there is any uphill slope.

I haven't tried driving with the IMA switched off, as I was cautious not to damage the car. But perhaps with the deep cycle 12V and the recharging gear and routine, it could function, it sounds like. Do you think it might be able to have enough power to get somewhere near highway speed with IMA switched off in that case?
Thank you again.
 

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