Alternator or.......?
- Thread starter Snake
- Start date
Jarrod B
Active member
A friend in Houston lost his 05 6.0 to the boarder run. Recovered abandoned and still in the body shop.
Goes to show you how much they know.. LOL
UPDATE
Checked all the grounds I could locate and didn't find anything that might indicate a problem, and tested again after unplugging the GPM. Unfortunately, that didn't change anything. At this point, the only suggestion I've received that might help is to run new grounds from each battery to the frame. Anyone have other ideas?
Checked all the grounds I could locate and didn't find anything that might indicate a problem, and tested again after unplugging the GPM. Unfortunately, that didn't change anything. At this point, the only suggestion I've received that might help is to run new grounds from each battery to the frame. Anyone have other ideas?
kyle43335
In the Brig (Banned)
- Joined
- May 18, 2011
- Messages
- 2,364
- Reaction score
- 0
did you check the fuseable links in the cable running to the alternator?
easy way to check them is to,hook a jumper cable in between the battery pos lug to the stud on the back of the alternator.
i also want you to clean your negative battery connections at the block. i have seen these connections error,but not cause a slow crank issue. sand paper,cookie on a die grinder will work fine.
Last edited:
kyle43335
In the Brig (Banned)
- Joined
- May 18, 2011
- Messages
- 2,364
- Reaction score
- 0
turn the koeo. check circuit (I) its the light green with the red tracer. make sure it has battery voltage. this voltage is supplied from the ignition switch,thru fuse number 45 in the central junction box. it also goes thru the charge indicator bulb.
the (A) circuit orange with light blue wire,is used for generator output.
it to has a fuseable link(E). to check,run a hot wire from the battery post to the alternator plug. back blade probe the plug,and check your voltage.
all the fuseable links i have mentioned can be found on the driverside battery terminal,about 4" down from the smaller red cable,that eyelets to the positive terminal.
one common area of concern is the alternator plug. with the heat and vibrations,the female cavities tend to loosen up causing various charging issues. easy fix is either,change the plug,or use a scratch awl and squeeze the cavities down to tighten the connection.
to check for this? start the truck wait until the alternator to start charging whatever it will. use a voltmeter.(NOT YOUR SCAN GAUGE) while watching your voltmeter,shake and bend,pull,and twist the wires around the plug area and see if the voltage jumps on the screen.
one of these areas will be where your issue is laying.
the (A) circuit orange with light blue wire,is used for generator output.
it to has a fuseable link(E). to check,run a hot wire from the battery post to the alternator plug. back blade probe the plug,and check your voltage.
all the fuseable links i have mentioned can be found on the driverside battery terminal,about 4" down from the smaller red cable,that eyelets to the positive terminal.
one common area of concern is the alternator plug. with the heat and vibrations,the female cavities tend to loosen up causing various charging issues. easy fix is either,change the plug,or use a scratch awl and squeeze the cavities down to tighten the connection.
to check for this? start the truck wait until the alternator to start charging whatever it will. use a voltmeter.(NOT YOUR SCAN GAUGE) while watching your voltmeter,shake and bend,pull,and twist the wires around the plug area and see if the voltage jumps on the screen.
one of these areas will be where your issue is laying.
Last edited:
Kyle -- much thanks for the guidance, and I'll try to summarize everything I've done to date. One big thing I just realized I failed to mention in this thread is that in addition to the factory wire running from the alternator to the passenger battery / between the two batteries, I'm also running 2/0 cable that was installed when I upgraded to the 200a alternator back in 2010. This didn't replace the factory stuff, but was added to it.
Keep me honest here please -- where are all the grounds? The one coming off the passenger side battery is obviously the easiest to trace, but I may have missed one of the others.
Thanks again!
Keep me honest here please -- where are all the grounds? The one coming off the passenger side battery is obviously the easiest to trace, but I may have missed one of the others.
Thanks again!
kyle43335
In the Brig (Banned)
- Joined
- May 18, 2011
- Messages
- 2,364
- Reaction score
- 0
the battery grounds as mentioned.
passenger side ground cable bolts to the block just to the inside of the a/c comp.
drivers side cable bolts to the frame and series off and goes to the block right below the ps pump.
make sure they are spotless.
when you unhook them look for shady,dark,black spots. even if you dont find them,clean them anyway.
to rule out a ground issue? you can always hook a jumper cable from a neg batt post to a clean conductive spot on the engine as well.
kyle43335
In the Brig (Banned)
- Joined
- May 18, 2011
- Messages
- 2,364
- Reaction score
- 0
well,is it fixed???
kyle43335
In the Brig (Banned)
- Joined
- May 18, 2011
- Messages
- 2,364
- Reaction score
- 0
you really shouldn't do that with computer controlled vehicles.
he should recheck the batts. i would(if i didnt have the ability to load test(which i do)batteries) unhook one at a time,and see what the voltage does with a dvom.
unhooking bolth batts while running,runs the risk of spiking the system,damaging the pcm.
the homework i gave him to do,most def will end in success...
And it did, but not quite the way I expected. LOL
I had planned on going through everything again, item by item, and retesting ater each change. For example, cleaning one ground and then seeing if the alternator was charging. If it was, then I found my culprit.
I knew that my batteries were getting weak through all the troubleshooting, so I put them on a charger Tuesday morning. Prior to charging them, I was reading alternator output in the high 11v / low 12v range and the batteries were showing 12.1v when disconnected. Tuesday evening, after the charge was complete, I started the truck to turn it around in the driveway (put the front end in the shade)..........and I saw 13.1v on the ScanGuage. Not believing what I was seeing, I checked output at the alternator and read 13.3v at idle. This is with an OEM alternator that tested good on the bench that wasn't charging the batteries the day prior.
I don't believe things magically fix themselves, so I sat on it and drove the truck to my in-law's house yesterday morning to go fishing. ScanGuage was showing 12.8 - 13.3v the entire time (lights on and A/C running) and read the same on the return trip home that afternoon. I was encouraged by what I was seeing, but still went back and double checked all the fusible links, voltage at the alternator connection, all the related wiring, and pulled and cleaned the grounds. Threw the DC Power 300 SPX on, fired the truck up, and read 13.7v instantly (both on the ScanGuage and on the multimeter). Glow plugs finished cycling and I saw 13.9 - 14.1v (mostly 14.0 - 14.1). Curious, I began turning on every electrical component within arms reach: 6" PIAA lights, A/C full blast, high beams with a 20" Rigid LED bar, stereo, seat heater, interior lights, air compressor, and aux coolant pump. The readings never dropped below 13.8, and that was a momentary dip.
While watching the multimeter, I started pushing and pulling on connectors, wires, and the other stuff I'd been over in previous efforts and saw no change in the numbers.
So it's resolved, but I don't know if I'd say it's fixed. I'm still not sure what happened or what was wrong, and the only thing I did was charge the batteries. :wtf:
I had planned on going through everything again, item by item, and retesting ater each change. For example, cleaning one ground and then seeing if the alternator was charging. If it was, then I found my culprit.
I knew that my batteries were getting weak through all the troubleshooting, so I put them on a charger Tuesday morning. Prior to charging them, I was reading alternator output in the high 11v / low 12v range and the batteries were showing 12.1v when disconnected. Tuesday evening, after the charge was complete, I started the truck to turn it around in the driveway (put the front end in the shade)..........and I saw 13.1v on the ScanGuage. Not believing what I was seeing, I checked output at the alternator and read 13.3v at idle. This is with an OEM alternator that tested good on the bench that wasn't charging the batteries the day prior.
I don't believe things magically fix themselves, so I sat on it and drove the truck to my in-law's house yesterday morning to go fishing. ScanGuage was showing 12.8 - 13.3v the entire time (lights on and A/C running) and read the same on the return trip home that afternoon. I was encouraged by what I was seeing, but still went back and double checked all the fusible links, voltage at the alternator connection, all the related wiring, and pulled and cleaned the grounds. Threw the DC Power 300 SPX on, fired the truck up, and read 13.7v instantly (both on the ScanGuage and on the multimeter). Glow plugs finished cycling and I saw 13.9 - 14.1v (mostly 14.0 - 14.1). Curious, I began turning on every electrical component within arms reach: 6" PIAA lights, A/C full blast, high beams with a 20" Rigid LED bar, stereo, seat heater, interior lights, air compressor, and aux coolant pump. The readings never dropped below 13.8, and that was a momentary dip.
While watching the multimeter, I started pushing and pulling on connectors, wires, and the other stuff I'd been over in previous efforts and saw no change in the numbers.
So it's resolved, but I don't know if I'd say it's fixed. I'm still not sure what happened or what was wrong, and the only thing I did was charge the batteries. :wtf:
Last edited:
Jarrod B
Active member
I think reading this thread caused my alt to go yesterday.
iPhone
iPhone
kyle43335
In the Brig (Banned)
- Joined
- May 18, 2011
- Messages
- 2,364
- Reaction score
- 0
so it was either the grounds,or the connector on the alternator. iwould tighten the connections in the alternator plug just for p&P. cant hurt....
Jarrod B
Active member
Well after going to two part stores to have batts tested, it was narrowed down to low alt output. New Oreillys alt and charges and starts like it should.
However I do know who now to contact for an issue tho......
:jammin:
kyle43335
In the Brig (Banned)
- Joined
- May 18, 2011
- Messages
- 2,364
- Reaction score
- 0
with him saying he cleaned the grounds,and put the dc back on(that i thought he said was on the truck all along),and now it charges.
i would say it was either the grounds,or a finicky plug on the alternator that just so happened to make a good contact this time...
Last edited:
Kyle, I think it has to be the grounds. Everything "fixed" itself before I touched a single wire, ground, or connector (or put the DC Power alternator on). Even though its working, I bought some more 2/0 cable and will be adding two new grounds this weekend.
kyle43335
In the Brig (Banned)
- Joined
- May 18, 2011
- Messages
- 2,364
- Reaction score
- 0
i would just make new grounds/battery neg cables if it were me.
make sure you put the grounds back where they were. dont move any main ground to the bell housing area. ive seen trans pumps weld themselves together.
trans go has a article on that topic.
