Rep Power: 0

2005 Civic DX
no modifications
160k miles

Son was driving the car and did not react to belt noises (I found this out later) - car stalled on him the next day, stranding him. He called me...
When I got to the car I did a quick check to see if anything major was obviously wrong (oil/liquid puddle, anything burnt, broken pieces coming off), nothing. It was already dark and he was on a side dirt road in the middle of nowhere. Using a flashlight I checked what I could, but finding nothing I decided to at least see if the engine would start. The engine started fairly easily and idled ok, but I could hear something around the belts so I shut it off.

Looking into it further I noted the missing alternator adjustment bolt and the inability to get tension on the belt. I also noted the upper bolt, large one that acts as the hinge, was almost completely backed out. So it would seem that not torquing the upper bolt and possibly over-torquing the adjustment bolt caused a failure of the adjustment bolt, the alternator rotated down, the belt went loose, the battery carried the load until it lost its ability to keep things going, and the car stalled.

I charged the battery for about 30min and then attempted to drive the car back to his apartment (<3miles). The car started fine. When I shifted into reverse there was a moderately hard "clunk", but it did go into reverse. I backed out onto the road and shifted into drive and got another moderately hard "clunk", but it did go into drive. I have very little experience driving this car, but I knew that this was not normal. I asked my sone if he had experienced this, and he said never. Driving back to his apartment the car drove very poorly: little to no acceleration, almost stalling, low revs the whole way. Going up a hill I thought it was not going to make it. But I got it back to his apartment, and when backing in - because I knew I'd be back to fix the alternator bolt - I experienced the same "clunk" going into reverse.

Fixing/troubleshooting:
I pulled the alternator to remove the remaining bolt piece
Re-installed the alternator
Charged the battery
Performed a code check - had trouble connecting and got weird results (only SRS failures) so I'm going to try again today
Test drive - this went poorly and I ran out of time to continue, and was getting pretty frustrated...

Current state:
Engine starts and runs fine
Car has no power
Transmission shifts with a "clunk"
CEL on
Code read intermittent and weird results (SRS only)
Clicking from front passenger side

Next steps:
Re-read codes
Check battery voltage - replace as necessary
Check alternator output
Check alternator grounding and leads
Check ECU/PCM fuse (#17, 15A "Fuel Pump")

Anyone see something I'm missing?

I feel like I'm getting to a ECU/PCM replacement, but I want to check everything I can first. I've read a few things that you should do before hand:
1. Check alternator/battery
2. Check "TCC" brake switch solenoid, I don't know what this is yet
3. It may take a few miles for the ECU/PCM to reset even if I fix things.

Any thoughts on those items or additions to the list?

Thanks for anything you can provide. I'm mechanically and electrically inclined and have a quality tester, tools, and ability, but I've never messed with a ECU/PCM and am trying to avoid it. I've read some of the posts here and, again, think that's where I'm headed but I want to check everything else first.

 
Rep Power: 0

So before you get too in the weeds, I gotta ask this. Is the current alternator an OEM honda unit, or has it been replaced with a parts store unit?

I ask because you might just have a one-two punch with 2 separate issues. But lets keep it simple for now.

The alternator tensioner system on a D17 Honda motor is what either makes or breaks unfamiliar techs with these cars. Either way you should get new oem hardware for the alt tensioner at a bare minimum.

 
Rep Power: 222

Might have fried the ecu. Get the alternator mounting sorted first though

 
Rep Power: 367

car-part.com for nearby scrapyard, get mounting hardware and used alternator (aftermarket alt does not work for these cars)

 
Rep Power: 0

I replaced the belt tensioner and adjustment bolt (OEM parts) and all seems to be good.

What do you mean by the tensioner system makes or breaks unfamiliar techs? This system seems very simple.

 
Rep Power: 0

I don't know if the alt is OEM or aftermarket, didn't think to check. I'll take a closer look and then get a used one if necessary. I've got a "you pull it" close by which has 5 or 6 donor cars (01-15 Civics).

 
Rep Power: 0

If the ECU is fried, what's the order of replacing it? This is what I understand:

1. Determine it's actually fried
2. Get a replacement - I'm looking at refurbished units around $350
3. Pull the old one and replace - passenger side front
**this is where I'm fuzzy**
4. Get it flashed by the dealership to synch with the key - can this be done by any locksmith?
5. Test the car with the new ECU.

Additionally, and I just realized this, he has an aftermarket remote start fob for the car. I'm trying to decide how that works if it's supposed to require a coded key to start.

Anyone have experience with an aftermarket remote start unit and replacing the ECU?

 
Rep Power: 367

nowadays, most locksmiths have the programming tools.

fried ECU's will not connect to OBD readers, that's the clue.
if it connects, should be ok

 
Rep Power: 222

Remote start immobilizer bypass may need to be reprogrammed, might work without programming.