Killed engine while testing A/C
 

2007 Honda Civic LX 4 door.

AC blowing hot air. Connected gauge to low pressure side while car was on and AC on max, read 100 psi. Worried about charging as it is above what the normal range is.

The compressor is not spinning, even though the belt is. was starting the troubleshooting.

Tried to test the AC Pressure sensor. Poked into the red wire with a Power Probe and was seeing 4 to 5 volts .. accidentally hit the 12V supply and it shut the engine down.

I cannot start the car again. It tripped a check engine warning light that does not clear.

HOW can I get the car started again ? How do I properly jump around the sensor or check if I maybe broke the wire inside the insulation where I broke it ? Need to have the car running again and then maybe just replace the clutch and compressor so I don't risk effing things up again ?

Re: Killed engine while testing A/C
 

Don't do that again, you can really cost yourself a lot of money.
Undo everything you touched and put it back as you found it.


Key off.
Disconnect the battery, touch cables together for about 5 minutes,
Pray to the deity of your choosing for this period of time.
Reconnect battery and see if it will run.


Then start over. Observe and answer questions.
Is the radiator full of antifreeze? (engine is not overheating)

When you turn the AC on, do the radiator fans turn on?

Re: Killed engine while testing A/C
 

Got a code reader and see the following 4 OBD's :

P1659 : google says one of these issues - ETCS Relay
- ETCS harness is open or shorted
- ETCS circuit poor electrical connection
- Faulty Engine Control Module (ECM)

P060A :

P0606 : In all likelihood the PCM/ECM has failed
In all likelyhood the PCM / ECM has failed

Read more at: http://www.obd-codes.com/p0606
Copyright OBD-Codes.com
In all likelyhood the PCM / ECM has failed

Read more at: http://www.obd-codes.com/p0606
Copyright OBD-Codes.com
In all likelyhood the PCM / ECM has failed

Read more at: http://www.obd-codes.com/p0606
Copyright OBD-Codes.com

P0498 : Faulty vent valve or wire/circuit issue

this looks bad

Re: Killed engine while testing A/C
 

Did you disconnect the battery like I said?

Re: Killed engine while testing A/C
 

eZone:

Disconnected battery cables, clamped them together for 10 minutes and put back on. Ca still turns over but will not fire .. same as before.

Still have the engine, oil and better dummy lights on.

Full radiator. Car is nice and cool .. been sitting for a long time now since it will not start.

Re: Killed engine while testing A/C
 

battery light .. not "better"

Re: Killed engine while testing A/C
 

Check all fuses in both fuse boxes?
Fuse 3 in the dash is for the evap cvs valve
fuse 21 in the engine compartment is for DBW (etcs)
But check all of the fuses in both boxes.

Go back to the AC pressure sensor, measure voltage on the red wire (VCC, specifically VCC6), whatcha got there? If it's nothing, then I think you may have fried the PCM.

Re: Killed engine while testing A/C
 

ezone: Firstly, thank you in advance for giving me some troubleshooting ideas. I do appreciate it.

Any more work will have to wait til tomorrow .. too dark now and I can't drive it into the garage.

I did start looking at some fuse box diagrams and am praying it is in there some where .. found where the ECU fuse is .. allegedly.

The ECU doesn't look too bad to change (money is scary, especially lots of other things hit in the last week (broken garage springs and broken water main) .. guess it is my week. If I can figure out where it is .. need to look.

I will check those fuses you mentioned and then some and post back in the am. Then check voltage if it does not start ..

This may be a dumb question , but what does VCC and VCC6 mean ?

Re: Killed engine while testing A/C
 

The P060x codes pretty much confirmed the PCM. I was hoping for a simpler solution but not holding my breath.


Yes, but it's not a simple plug-n-play.
Add in towing to a dealership and a fee for programming it before the engine is allowed to run.
Gather up ALL of your keys for programming and take to dealership. Any keys not programmed at that time will not start the car.


Sensor supply voltage, in this case it's #6 of the various groups in the powertrain computer intended for sensor use. Power from this VCC#6 is shared with the FTP sensor IIRC.
Vcc short definition (link)
Another definition (link)

Re: Killed engine while testing A/C
 

Fuses all good.

I was reading 0 volts on the red wire I poked the other day (formerly 4 to 5 volts).

Re: Killed engine while testing A/C
 

Sounds like it's done. Stick a fork in it.

You do know the car will still have the original AC problem when this is over, right?

Re: Killed engine while testing A/C
 

Sadly, yes, yes I do.

I'll get it taken care of while the ECM is getting replaced.

Re: Killed engine while testing A/C
 

ezone, having trouble finding info on changing the ECM/ECU in the car. Have Vol 1 and 2 of the official Honda Service Manuals, but they do not have an index that I have discovered.

I understand if I change the unit myself, I still will not be able to program it.

Doesn't look like there is much to swapping the part. Your opinion ?

Also, thoughts on used ECM's from a parted car or new ? Dealer says $700 for part + labor, import shops, so far I cannot get a hold of .. leave messages with no call back. I see sites such as HondaVillage.com and others that claim OEM parts for around $400 to $420 (I need the 37820-RNA-A68 ). The ones from parts cars ( partmyride.com ) are around $100 with shipping.

Re: Killed engine while testing A/C
 

Behind the battery, a plastic cover has a couple tabs and it pulls straight up, 3 bolts/10mm wrench or socket, 3 harness connectors--easy peasy.
Disconnect the battery first.

No you won't be able to program it yourself.

There is a chance that a brand new 'blank' unprogrammed PCM can start the engine, and if it does this you need to drive directly to a dealership RIGHT NOW because the PCM will only give you a very limited number of "free starts" before locking you out. Don't stop to get smokes or a burger on the way, you could get stranded.

A new PCM will need to have the cars VIN 'written' into it, AFAIK a dealer level scanner is needed for this. (I really don't have experience with aftermarket scanners.)
Dealer level or locksmith level access is needed to program immobilizer and key functions.

I cannot tell you anything about using a used PCM, I've never attempted that myself in one of these cars. Might be worth trying if it's only 100 for the part, plus programming fees no matter what and maybe a tow bill.
I really don't know if the VIN can be re-written in a used PCM either, and you're back to needing a high level scanner again to attempt that.

I am of the opinion that that generation of PCMs have been pretty dang reliable, barring wiring issues, shorted components/sensors, or haphazard stabbing of wires like you found yourself......so a used PCM might be a viable option if it can be programmed to the car ok.


If you have more than one Honda or Acura dealer available, call and ask prices on programming. They may vary. I know for a long time our shop was half the price of the 3 next closest dealers on programming keys.

PCM location:

http://www.8thcivic.com/images/diy/h.../hondata01.jpg


I wrote this part before I thought about having to 'write' the correct VIN into the PCM with a scanner, so it may be irrelevant:

Maaaaybe a well equipped local locksmith can program the immobilizer for the keys, IDK. In my town it's dealer only.

If you want to try import shops you better ask if they can program immobilizer keys first. If they don't have a scanner that is capable of doing that then don't bother with them. Make sure they agree that if they can't do what you need they won't charge you.



Did all this make sense?

Re: Killed engine while testing A/C
 

Yes sir. All made sense. Now to try to get an answer from local dealer.. so far I have asked questions, they didn't know and said they would call back, but not a peep from them. Same thing on Sunday on other questions for price estimates.

Not filled with fuzzy warm feelings.

Re: Killed engine while testing A/C
 

If you are asking about stuff they don't normally do, you should expect that.

Price for programming a PCM, or keys, calibration, or whatever control units at my dealer is a somewhat standard 1 hour labor fee, whatever that dollar amount is.
Software updates (reflashes) are a little less for most cars though at our shop. Your local shops may vary on price or labor rates, there is no standard set rate for any of this.

There's no way I could give someone on the phone a solid answer answer about programming a used PCM because I've never tried it (of course it isn't in the service manuals), the best I could offer is to connect my scanner and see what I can do with it.
I'm betting that's what your local dealer would have to try also....unless someone there has successfully done it and the service advisor you spoke with asks the right tech who remembers doing it.

Re: Killed engine while testing A/C
 

ezone, do you think there could be a chance that if the red wire on the AC Pressure Sensor is broken that it would keep the car from starting ? Maybe I broke the wire with the tip of the power probe ? Problem is there is no slack on that darn thing and it is only inches long. Curious how and where I could test it.

Re: Killed engine while testing A/C
 

No, the engine will run with the AC pressure sensor unplugged. If only one wire broke the computer would set a high or low signal code as a result.
It's not a critical sensor for engine operation, but the internal PCM failure is critical.

I think you probably shorted out the VCC line to ground and wiped out the component that regulates that voltage supply. You should find the FTP sensor also lost its 5v reference voltage too, it shares that same VCC6 circuit.

Your P060x codes are internal failures in the PCM.
P060A troubleshooting is short and sweet: erase code, see if it returns. Try a known good PCM.

P0606 has a TSB about not using aftermarket spark plugs with a built in capacitor as they cause electrical interference. Otherwise, troubleshooting is about the same as above: Erase codes. If it resets the code try a known good PCM

Re: Killed engine while testing A/C
 

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I did the exact same thing but still have 5 volts on the red wire but still no start.

Re: Killed engine while testing A/C
 

Got fault codes?

Re: Killed engine while testing A/C
 

Did you ever fix it

Re: Killed engine while testing A/C
 

Yes, I did fix it. Found a ECM online, came from NY area, installed it .. car would run for about 3 seconds then die immediately.

With help of this board and googling, discovered that the ECM would have to coded to the car. As soon as it is used, it checks to make sure it recognizes the car it is in .. if no match, then it kills the engine.

Towed it to a dealer and they reprogrammed it, only took a few minutes but call around to see who can help you .. maybe some private garages as well as they want $100 or more to program it.

Re: Killed engine while testing A/C
 

Ezone I have a 2009 honda civic. Will crank but wont start. Throwing codes for ECM p1659a p0606 p0498. Any help? The ac wire has 5 volts to it

Re: Killed engine while testing A/C
 

Did you read the thread? Perform the same troubleshooting.