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Discussion Starter #61 (Edited)
I made a mistake and did not follow Mike's advise. I replaced my alternator...

Waste of money, still have the problem. It was NOT the alternator.

Found a few threads on here (old ones) where people had similar issues hut they never posted a solution if they found one.
 

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Discussion Starter #63
I now have a spare alternator. I have thought about getting a voltage regulator made for an older truck that does not use the computer and just run it old school.
 

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I thought about myself but it's gone now.

Technically you could just get a 14V regulator from Digikey with high enough current capacity and install it in series with the alternator and call it a day. But, I'm still betting it is the computer. I found computers online for about $200. You just send them your VIN and it comes programmed. That was going to be my next step but when it wouldn't start and I had to go to work, I was done.
 

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Now that I have read the entire pages, found out you sold your truck, I wish I had told you about my issue with the loud alternator in the first post to this thread. Right after I purchased my 2006 Canyon, my alternator was making a very loud noise when the A/C compressor came on, it continued to make noise, just not as loud with the A/C compressor off. Went to Wal-Mart and it needed a new battery. After replaced, noise from the alternator was normal. And has been normal. On page one or two, you stated your battery was 2 1/2 years old. Even though it might still be under warranty, it is possible that it is bad. The fact that you went to work, car would not start, windows inop, to me points to the power source. Good luck with your new truck.
 

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Discussion Starter #66
Now that I have read the entire pages, found out you sold your truck, I wish I had told you about my issue with the loud alternator in the first post to this thread. Right after I purchased my 2006 Canyon, my alternator was making a very loud noise when the A/C compressor came on, it continued to make noise, just not as loud with the A/C compressor off. Went to Wal-Mart and it needed a new battery. After replaced, noise from the alternator was normal. And has been normal. On page one or two, you stated your battery was 2 1/2 years old. Even though it might still be under warranty, it is possible that it is bad. The fact that you went to work, car would not start, windows inop, to me points to the power source. Good luck with your new truck.
I think you are talking about Mike... He sold his truck. He was having similar issues to me.

I still have mine and I have been trying to figure it out... Not willing to quit yet.

I will make another reply and try to recap everything I have done.
 

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Discussion Starter #67 (Edited)
This reply is an attempt to recap everything up to this point:



When my engine bay warms up, my electrical system will start to have high voltage (up to 18 volts) normally associated w/ acceleration or increased load on the engine. At idle or just maintaining speed, it will run about 13 volts. This voltage is confirmed on the OBD2 pin 16 and also from the IGN1 signal from a Tech2 Scanner.



1. Battery is about 9 months old (Autozone battery... not sure if that is potential problem)

2. Battery ground cable replaced. Verified the engine block connection is clean bare metal.

3. Cleaned Splice Pack ground down to bare metal for G105. (Fender)

4. Cleaned Splice Pack ground down to bare metal for G106. (Fender)

5. Cleaned ground connection for G101, 102, 103 (sensor grounds on engine block)

6. Added jumper wire from G101, 102, 103 straight to negative battery terminal

7. Cleaned to bare metal the ground connection behind battery to inner fender

8. Opened wiring harness from PCM to underhood fuse block looking for burnt, bent, broken... wires.

9. Used electrical contact cleaner on PCM and associated connectors.

10. Used electrical contact cleaner on ALT connector.

11. Visually inspected connector at PCM for anything visually "odd".

12. Scanned PCM w/ Tech2 - Does not generate any Codes while the issue is happening.

13. Data logged w/ Tech2 - nothing I have noticed. PCM, BMC, IPC, and ABS all see the varying voltages.

14. Tech2 signal to Alternator as reported by Tech2 is NOT ramping up, so appears that Alt is not raising voltage due to signal from Tech2 (as reported by Tech2).

15. Battery + cable replaced w/ GM original (bat to mega fuse and to starter).

16. Alternator tested by Autozone and Advcanced Auto (numerous times, different locations)

17. Mega Fuse replaced.

18. Replaced Alternator w/ brand New Remy brand. Exact same issue w/ new Alt.

19. Had old alternator bench tested (off truck) at Autozone and Advance Auto.

20. Used carbon pile load tester on battery and alternator. Did "voltage drop test" between Alt case to (-) Battery Terminal and about every other combination I would imagine.





I think that about captures all I have tried. Not necessarily in correct order.



For next steps:



1. Use some Micro64 test leads and check the pins on the PCM and Connector to see if any feel "loose" (also called a drag test).

2. Do similar test on the connection to the Alternator.

3. I have replacements terminals to install on PCM and Alternator connectors if any seems "suspect".

4. Will do similar check on BCM harness (the BCM talks to PCM and requests higher voltage based on items turned on by BCM).

5. Lastly... if nothing else checks out... Replace PCM.



I would really hate to replace the PCM and have it not be be problem, but I cannot figure out a way to ensure the PCM is faulty in any way. The @$$hole at the dealership told me my truck was too old for it to have a PCM controlled Alternator. I explained that the factory service manual description and wiring diagram said it was. He explained I did not know what I was talking about... They now will never get any business from me...



Older versions of the AD244 alternator had a 4 wire volotage regulator (not PCM controlled). I thought about maybe installing one into my old alt and run the truck that way. I think I would have a constand BAT warning light on dash that way, though.



I have found a few posts where others seemed to have a similar issue, but they never posted a follow up w/ the SOLUTION.



This thread has over compensated for them and I have made WAY TOO many updates. :)



Trust me, when I do figure it out, I will post it.
 

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I know it sounds silly, I still think your battery is your issue. When I was in SA, Mobil oil had a villa on the Red Sea. They had a reverse osmosis plant there. One weekend when my family was there, I was looking at the system and a “Engineer” came in, and as we talked, he began to tell me that the biggest complaint he had, was the bank of batteries for the system kept failing. I looked at them(this was in the middle 1980’s, and ALL of them were sitting on the concrete floor. I explained to him that the reason for the lack of capacity was do to the fact that they were loosing current thru the concrete. He purchased a piece of wood and set them all on it and the problem was solved. I still think that your battery is your issue. Like I said somewhere in a previous post, some times you get so hung up chasing electrical gremlins, you can’t see the forest for the trees. Hope this helps.
Everett
 

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Discussion Starter #69
Thanks for the suggestion.

I have an older truck w a side post battery. I will get some side to top adapters and see if that helps.
 

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Ken23434,
I don’t think that the addition of “adaptors” will correct your issue.
 

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Discussion Starter #71
I meant using adapters to use a side post battery in my truck which has cables meant for top post battery.

That way, I spend about $10 to check the battery issue vs buying a new battery.

The battery in my Collie passes a carbon pile load test and the little handheld battery testers used by the part stores.
 

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Hhrumph - When I was a teen, I learned that while working at a service station in the 70's. I never understood it, but I learned - more than once - that a battery will discharge if left on a concrete floor. I learned a lot of tricks from good 'ol "Crescent wrench and screwdriver" mechanics. Like, a box of pepper will fix a leaky radiator or water pump for about a month. A wooden clothespin on a metal fuel line will help if you have old gas or water in your gas. I swear, I've seen this work! The foil paper in a cigarette pack can be wrapped around an old glass fuse that's blown and get you around until you can replace the fuse. Interesting times! The owner of the service station would adjust the points in a car by grabbing a spark plug wire with one hand and pointing the index finger of the other hand at the engine block. If he could get an arc between his finger and the engine block that was about a 1/2", the point gap was correct! He used to love to grab a plug wire with one hand and one of us teenagers with the other hand and ask us if we think the distributor was working!
When we questioned this apparent "addiction" to having electricity running through his body on a regular basis, he said that he felt that "an occasional exposure of your body to electric shock is good for your heart!" "If not, why do they use it to bring dead people back to life?"
He was an interesting individual!
Those were good times!
 

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Discussion Starter #74
Well, yesterday I opened up all 3 connections at the PCM again.

I used some test micro64 cables to check if the voltage or ground connections were loose. They seemed to fit as tight as the other connections.

I was excited a couple times when I noticed something odd.

Turns out that dark spot is associated w a locatyw no PCM pins or sockets.

I reassembled everything and then took apart the connection at the alternator. The sockets were clean and felt tight w the test pins.

I think the only remaining options are replacing the PCM or the truck. :th_crazy:
 

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I would be concerned with the dark spots too. That looks like something was overcurrent. This may only be a symptom of the 18V from the Alternator though.

Before I sold Reliable Red, my next step was to replace the PCM. I searched and found a few placed online that were relatively inexpensive, but I seem to recall the PCMs were all used.

Assuming that is the problem, here is my concern with a used PCM: Since you and I have the same problem starting at about the same time, it is reasonable to think there is a failure that is related to time. Now, I have never opened a PCM before, BUT I would bet there are some electrolytic capacitors inside the PCM. These parts have a tendency to dry out over time and as I recall, during the early to mid 2000's there was a huge batch of capacitors that were being used by manufacturers that were faulty. It was so bad they called it the Capacitor plague. https://en.wikipedia.org/wiki/Capacitor_plague

Just my thoughts on the subject. I do not know how easy it is to remove the top of the PCM and see what is inside. If it is accessible and there are indeed bad capacitors, it is an easy fix for a couple of dollars.
 

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Discussion Starter #76
I read somewhere on a forum discussing engine swaps, that the AD244 alternator would run at a constant 13.8 volts if "the other wire" is not connected.

Problem is, I cannot determine which of the two they are referring to.

I think I could drive w a constant 13.8 w out much issue. That would be enough to charge the battery. Most of the time my truck runs at 12.8 to 13 volts. The 15+ volts is only during acceleration or hill climbs, so only a few seconds.

If it did run at 13.8 steadily, then that should confirm the problem is the PCM connection. However, both wires do go to the PCM.

PCMs of NC will sell a replacement PCM programmed for $205. I am not sure if that is a new or refurbished unit.
 

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Since there are only a couple of wires, it should be easy to find the one. It is the one with a PWM signal. If you have a scope it would be easy. Process of elimination
...pull one wire and it will either be the enable or the correct wire. :)
 

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Discussion Starter #78 (Edited)
I wish I had a scope. Actually was looking online today at a few.

I was going to pull one wire and test, but it was raining and I was not willing they set. Maybe tomorrow.

I think it is the Field Duty Signal wire that would be disconnected.
 

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Yes... that is the PWM signal. Nothing but a square wave of sorts... varies the duty cycle of the signal depending on the desired output. I found a chart online for the cycle a month or two ago.
 

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There are a few "entry level" scopes available. The one I have is a Hantek 1008C. It works well, but you would have to go to the Hantek website and download the needed software. The included disc is reported to be unreliable. It was a bit tricky, but works good with both of my laptops, a Win7 and a Win10. https://smile.amazon.com/Automotive-Diagnostic-Oscilloscope-bandwidth-Generator/dp/B07DKYR9X6/ref=sr_1_4?keywords=hantek+1008&qid=1565006163&s=gateway&sr=8-4

Hantek also has a less expensive 2 channel scope. It has pretty good reviews. I just chose the 1008 for the extra channels. https://www.amazon.com/gp/product/B009H4AYII/ref=ask_ql_qh_dp_hza

I don't do any automotive work on a professional basis, so a more expensive scope wouldn't provide me with any benefit.

There are some related videos on Youtube. Just search Hantek 1008C
 
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