2010 6.4 erratic charging
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Tuned
Joined: Aug 2003
Posts: 285
Likes: 5
From: Mena, AR
2010 6.4 erratic charging
I have a 2010 6.4 with 240K miles. Over the past few days I could hear the alternator whining. Today, it set the battery light and it smells like hot electrical stuff. So, changed the alternator and the batt light is still on. Checked the amps and its all over the place. Charging 10, 25, 60 amps and up. Isolated the batts and checked again. No change. The only alternator available was an Autozone reman. I hate that but had to try it. Any ideas? I know that the sense circuit can chaff but I didn't see any bad wiring. And of course this is my service truck for A/C and I'm swamped with calls. Argh! Any help would be appreciated. I suppose I will try to find any wiring issues but I don't know where to start. Thanks.
Thread Starter
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Tuned
Joined: Aug 2003
Posts: 285
Likes: 5
From: Mena, AR
Update to last nights work... so, I have the P0625 code stored in the PCM. I've traced wiring back and see no scuffs or missing insulation. I've checked my fusable links coming from the alternator output and they have continuity. I checked the red control wire on the alternator and it has battery voltage with key in on/start position. Once started, the red wire at alt. control terminal shows .003 volts so I assume that the diode is good. I've unplugged and plugged back the main PCM harness on the pass. side. I'm at a loss. Is there another test for the alt. without taking it off and bench testing? It's an autozone so I would not doubt that it could be bad. When the engine runs, I get voltage output to the batts at around 13.5 which rises until it hits 14.5 and then falls again. I've watched the output on both volt and ammeter and it just ramps up and then resets just as I would think with the 0625 code. Just don't know where to turn. Ideas?
Thread Starter
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Tuned
Joined: Aug 2003
Posts: 285
Likes: 5
From: Mena, AR
I did not bench the original alt. I smelled hot electrical stuff and assumed (yeah, I know) that the original alt. was bad. It had been whining and had known milage of at least 100k plus more so I just replaced it. The batt light set at the same time so I figured what the heck, new alt time. It is an Autozone reman. so I don't know what to think. I need a ford P0625 diagnostic step by step.
Cargo Master
Joined: Nov 2005
Posts: 2,768
Likes: 58
From: East Tawas, MI
OK,
So it could go either way that it is truck side or alt side at this point.
Do you have a means to delete/clear the code? If not unplug both negs for a few hours and hook em back up.
At first start KOEO you should see voltage drop to about 10.5-11ish. After the glow plugs are timed out it should rise to 12- or better. Upon starting it should ramp to 14-14.5 depending on what you have running.
If your alt is working it should stay in an area of 13.5 (Low) or preferably hang out at the 14 + mark.
First thing I always do is a wiggle test with the truck running and a heavy eye on the voltage. I suspect you have a multimeter being in your line of work.
Grab each loom (No hoodie with strings or loose clothing) and give each a decent workout while watching voltage.
If you see a dip, repeat and inspect the source loom.
Questions:
Does it still smell like burning?
Have you pressure washed the engine compartment?
Does everything electrical on the truck still work?
How old are your batteries?
Have you surgically cleaned all ground connections and the battery terminals?
Do you/ or did you have any blown fuses or relays?
Denny
So it could go either way that it is truck side or alt side at this point.
Do you have a means to delete/clear the code? If not unplug both negs for a few hours and hook em back up.
At first start KOEO you should see voltage drop to about 10.5-11ish. After the glow plugs are timed out it should rise to 12- or better. Upon starting it should ramp to 14-14.5 depending on what you have running.
If your alt is working it should stay in an area of 13.5 (Low) or preferably hang out at the 14 + mark.
First thing I always do is a wiggle test with the truck running and a heavy eye on the voltage. I suspect you have a multimeter being in your line of work.
Grab each loom (No hoodie with strings or loose clothing) and give each a decent workout while watching voltage.
If you see a dip, repeat and inspect the source loom.
Questions:
Does it still smell like burning?
Have you pressure washed the engine compartment?
Does everything electrical on the truck still work?
How old are your batteries?
Have you surgically cleaned all ground connections and the battery terminals?
Do you/ or did you have any blown fuses or relays?
Denny
Thread Starter
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Tuned
Joined: Aug 2003
Posts: 285
Likes: 5
From: Mena, AR
Yes, I can clear the code an also have a Giotto PC based system that I can live track.
I start the truck and have a clamp ammeter to watch the charge. At idle, amps ramp up to 80 and then it falls back to a baseline and then starts all over again. Same thing with voltage. Starts at 13... and ramps up to a max of 14.5 and then drops to a baseline again. it seems cyclic. To me, it is running through a cycle and awaiting a reply from the PCM. I don't know if that's correct.
I've wiggled harnesses while watching voltage and don't see any big difference.
I only notice burning or hot electrical smell if I really get on the throttle and it charges far too much.
Have not pressure washed anything.
Everything electrical still works.
Batt's are relatively new. I've isolated and they are 12.7 static. Truck cranks fine.
I've not cleaned all connections as of yet but I did look at grounds and such. They seem ok.
I've not inspected all fuses but did check all under the hood fuse block that pertain to the CAN bus.
Can this be a bad new alternator? I don't think it is but I've noticed some that state that anything other than a ford OEM will not work well.
I start the truck and have a clamp ammeter to watch the charge. At idle, amps ramp up to 80 and then it falls back to a baseline and then starts all over again. Same thing with voltage. Starts at 13... and ramps up to a max of 14.5 and then drops to a baseline again. it seems cyclic. To me, it is running through a cycle and awaiting a reply from the PCM. I don't know if that's correct.
I've wiggled harnesses while watching voltage and don't see any big difference.
I only notice burning or hot electrical smell if I really get on the throttle and it charges far too much.
Have not pressure washed anything.
Everything electrical still works.
Batt's are relatively new. I've isolated and they are 12.7 static. Truck cranks fine.
I've not cleaned all connections as of yet but I did look at grounds and such. They seem ok.
I've not inspected all fuses but did check all under the hood fuse block that pertain to the CAN bus.
Can this be a bad new alternator? I don't think it is but I've noticed some that state that anything other than a ford OEM will not work well.
Cargo Master
Joined: Nov 2005
Posts: 2,768
Likes: 58
From: East Tawas, MI
I hate to say this:
I, at this point would get an OEM alt (bench tested before paying for it) and install it. It is the path of least resistance to spend an hour replacing it than spend sleepless nights and weeks of dicking with wiring runs at this stage.
I would also take back the AZ alt and have that bench tested as well before getting your refund to see if it was indeed the internal regulator taking a vaca.
I know they're more expensive (OEM), and I hate doing things twice, but that's why the forum insists on OEM Ford only configurations. Far too many veterans of Diesels in here to discard they're warnings about aftermarket units. I'm one of them and learned many years ago on my 7.3.
Question: Did you have any problems with this system before your original took a ****?
Denny
I, at this point would get an OEM alt (bench tested before paying for it) and install it. It is the path of least resistance to spend an hour replacing it than spend sleepless nights and weeks of dicking with wiring runs at this stage.
I would also take back the AZ alt and have that bench tested as well before getting your refund to see if it was indeed the internal regulator taking a vaca.
I know they're more expensive (OEM), and I hate doing things twice, but that's why the forum insists on OEM Ford only configurations. Far too many veterans of Diesels in here to discard they're warnings about aftermarket units. I'm one of them and learned many years ago on my 7.3.
Question: Did you have any problems with this system before your original took a ****?
Denny
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Thread Starter
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Tuned
Joined: Aug 2003
Posts: 285
Likes: 5
From: Mena, AR
That's the path that I'm taking. I took the original alt in, tested and it was bad. Barely turned when it was loaded and failed all tests. The new (reman,) from Auto Zone showed to test good but it didn't have a result for the diode test. Claimed to be inapplicable. Not sure what to think about that. Thankfully they took it back.
I've had no trouble out of the electrical system with this truck until now. The alt had at least 100k on it (that I was certain of) and maybe more. I've never changed it until now.
Now it's time to find an OEM. I'm certain I'll have to order it.
As always, thanks for the help! Much appreciated.
I've had no trouble out of the electrical system with this truck until now. The alt had at least 100k on it (that I was certain of) and maybe more. I've never changed it until now.
Now it's time to find an OEM. I'm certain I'll have to order it.
As always, thanks for the help! Much appreciated.
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Thread Starter
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Tuned
Joined: Aug 2003
Posts: 285
Likes: 5
From: Mena, AR
The saga continues. Turns out the truck had a 200 amp alt. from the factory. The alt from Auto Zone was a 125 amp. I drove all over the place and finally found a Ford OEM 200 amp that's listed for the truck. Installing Sunday and hoping that the 125 amp turd from AZ didn't mess up my PCM. The ford tech said it could possibly harm the computer. To be continued.....
Thread Starter
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Tuned
Joined: Aug 2003
Posts: 285
Likes: 5
From: Mena, AR
Motorcraft 200 amp alt. installed. Amp readings at idle are stable but still around 22-25 amps @13.2 volts. At least things have calmed down quite a bit but I have some concerns. When I read the PID's on my Auto Enginuity OBD2 I wasn't happy with some of the results. At idle, I get the following:
Gen Command = 0
Voltage desired = -1.86
Gen Monitor = 36-41
I have no battery light and no other faults. Also no hot electrical smell as before. I think the voltage desired at alternator should be around 13 or so and it ain't. Not sure what to think. I isolated batt's again and didn't find much difference. Added a little bit of distilled water to batts as well. Guess I'll drive her and see what happens. Did Mention that I hate electrical problems!!! Always a PITA.
Lesson learned..... always input the VIN when ordering parts! NEVER buy AZ crap!
Again, thanks for the help. Denny is always appreciated. He helped me immensely when I rebuilt a 7.3 fuel system with injector cups and such. Thanks man!
Gen Command = 0
Voltage desired = -1.86
Gen Monitor = 36-41
I have no battery light and no other faults. Also no hot electrical smell as before. I think the voltage desired at alternator should be around 13 or so and it ain't. Not sure what to think. I isolated batt's again and didn't find much difference. Added a little bit of distilled water to batts as well. Guess I'll drive her and see what happens. Did Mention that I hate electrical problems!!! Always a PITA.
Lesson learned..... always input the VIN when ordering parts! NEVER buy AZ crap!
Again, thanks for the help. Denny is always appreciated. He helped me immensely when I rebuilt a 7.3 fuel system with injector cups and such. Thanks man!
Cargo Master
Joined: Nov 2005
Posts: 2,768
Likes: 58
From: East Tawas, MI
Glad to help. Always
However, Again I hate to say it, but your far from done.
Follow me.
Your alt smoked, OEM, ok 100 plus miles I get that.
You get a barn find from AZ and it's amp rating is grossly under demand..............So you noticed the deficiency right away. System damage I think not. Overvolt is the enemy.
So we flip a page and go OEM and now your in a deficit for charging.
I think it's a matter of days that you'll have another charging problem.
Start pulling some fuses if your not pulling codes. You've got an intermittent short.
Somethings not right truck side is what I'm saying.
Look at every hardpoint the wiring loom contacts. You'll need a headlight, 4 wobbly pops and 1/2 pack of smokes. It's a one and done inspection so do it surgically.
Somethings pulling voltage pretty hard, but in brief stints.
My 2
However, Again I hate to say it, but your far from done.
Follow me.
Your alt smoked, OEM, ok 100 plus miles I get that.
You get a barn find from AZ and it's amp rating is grossly under demand..............So you noticed the deficiency right away. System damage I think not. Overvolt is the enemy.
So we flip a page and go OEM and now your in a deficit for charging.
I think it's a matter of days that you'll have another charging problem.
Start pulling some fuses if your not pulling codes. You've got an intermittent short.
Somethings not right truck side is what I'm saying.
Look at every hardpoint the wiring loom contacts. You'll need a headlight, 4 wobbly pops and 1/2 pack of smokes. It's a one and done inspection so do it surgically.
Somethings pulling voltage pretty hard, but in brief stints.
My 2
Thread Starter
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Tuned
Joined: Aug 2003
Posts: 285
Likes: 5
From: Mena, AR
Ok, so I killed the electrical loads that I could think of including the 1000 amp radio, and at idle, the amp draw is 3.5 with volts about 13.9. As soon as I turn on the A/C, it increases but not near as much as when the radio amp turns on. Silly part is, I never listen to the radio! It's always volume down but not off. I checked the generator desired voltage with everything off and I'm still getting a -1.5 to -2.0 volt reading. What the hell?
Cargo Master
Joined: Nov 2005
Posts: 2,768
Likes: 58
From: East Tawas, MI
Dive in. Inspect the hard points, Disable the batteries and pull cab off connectors and grease if dry. Reapply and see what we see. Just takes one in what seems like a mil.
Denny
(cab ever been off your rig?)
Denny
(cab ever been off your rig?)
Thread Starter
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Tuned
Joined: Aug 2003
Posts: 285
Likes: 5
From: Mena, AR
Cab has never been off. I'll keep lookin for bad wiring. Oddly enough, I disconnected both plugs going to the PCM and broke one of the locking cams. Go figure. In the meantime, I'll drive it and see what happens. The roads I drive are less than great. I go through one set of tires every year with no more than 28K per set. Lots of gravel and potholes. Arkansas. Love it:hate it! I was up close to your neck of the woods last summer. Our Son got married in Madison WI. Not terribly close but not that far. Truck made it all the way up and back.
I have to think that some of the plugs could be dry. After all, it is a 2010 model. If you ever need any A/C help, let me know! You've been very helpful. Appreciate it!
I have to think that some of the plugs could be dry. After all, it is a 2010 model. If you ever need any A/C help, let me know! You've been very helpful. Appreciate it!