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i have a 05 f350, new alternator and new batteries, i have been having a problem with battery voltage,, start up is a 5 second crank on when cold, sometimes 3,, so i get 2 attempts at starting it before my batteries are dead, the voltage reads sometimes 12.6 and others 12,3, which is not consistant, i know its suppose to be 12.6 and 14 at alternator, with taking 2 to 3 minutes before reaching max output at alternator, so why are my batteries not fully charging? why is my voltage low? and how do i fix it? I have checked for a parasitic draw and have not found one, hoping to get some help here while its warm to fix it
1. New parts aren't always good parts
2. Glow plugs drawing some fairly high current will keep the voltage down until they shut off
3. A bad glow plug system can drain batteries, you should check for codes with a quality code reader
4. If your batteries are wet cell batteries, then fully charged they should be 12.7 volts (after a surface charge has been dissipated). 12.3 volts means that the battery is about half dissipated (or more).
5. You probably should charge and then individually load test each battery, even though they are new.
6. Any parts store can test the alternator
7. Check all cables and connections - especially grounds.
each battery was tested and both passed,, alternator was also tested and passed, i tried to do a glow plug test and both banks read zero, , the resistance was suppose to be .05 to 2 ohms,, which i found weird, cause that tells me they are all failed,, yet it starts, which is also weird
That said, how were the batteries tested? How many amps of load were put on them?
How were the glow plugs tested? Individually, or was the wiring harness also included in the test? I don't see how a result of zero resistance is possible for each glow plug if the wiring were part of that test.
It would still help to see if there were any codes.
my code reader is not a good one, i plan on going to a shop to geta a reading today, the glow plug test i did was at the GPM, by removing the harness connection and testing there, I have yet to access the glow plugs themselves and test individually, I can get new ones for 12 bucks CAD a piece, but do i need to is the question, if they were not working the truck would be struggling to start, if at all, so the engine behavior tells me at least some are working
I am not sure why your test at the glow plug harness would show 0 ohms of resistance on each plug. I don't see how there could be a short in every wire and every plug. Maybe something wrong with the testing? Hard to say from this side of the screen.
I probably wouldn't be thinking about removing the glow plugs just yet. The issue sounds more "involved" than one or two glow plugs.
Do you have a way of measuring DC amps - say 300-400 amps? An inductive meter (clamp on) is a handy tool.
the only meter i have is a mastercraft multi meter, which i think only reads to 10 amps, and yes it has me stumped also,, i actually have 3 of these meters and all 3 read the same, not sure how to test the meter itself to see if it works, perhaps they are all messed up,, not sure
hey here is a question,, in that video it takes 8 seconds to get red hot,, my glow plug dash light turns of at about 8 seconds telling me its safe to start,, what controls the time they should be activated for? perhaps i am not getting enough heat before start up? sometimes, i run the glow plug cycle 2 times, and it starts in about 3 seconds of crank
The glow plug light on the dash has nothing to do with the actual length of time that the glow plugs are on.
IMO you should NEVER cycle the glow plugs with the key like that. It is not needed.
The PCM will decide how long the glow plugs need to be on (based on oil temp, BARO, and battery voltage). The PCM will command up to a MAXIMUM of 2 minutes for the glow plugs. The GPCM has an internal limiter that will stop glow plug operation after 3 minutes - assuming it is all working correctly.
The PCM will not command the glow plugs if the oil temp is 131 degrees F or higher. In the case of hot oil, the glow plug light on the dash might be on at "key-on", but the glow plugs will not be.
IMO the proper way to check for resistance is with both of the plugs removed at the same time (ie green and black plugs both removed). Also, it is best to remove the GPCM before removing the plugs, just so you won't have to struggle with the plugs and possibly damage them.
i disagree,, the glow plug light as u call it has everything to do with start up, its what creates the heat needed to start the engine, elements of any king will burn out over time, there is 260000 km on this engine, so the longer it stays on the more heat produced,, i wonder what temp is required to start and how to test that
i disagree,, the glow plug light as u call it has everything to do with start up, its what creates the heat needed to start the engine, elements of any king will burn out over time, there is 260000 km on this engine, so the longer it stays on the more heat produced,, i wonder what temp is required to start and how to test that
It is all in the manual - disagree all you want.
When I say the glow plug light, I am referring to the light on the dash (I added that to the above posts for clarity ...). It, the dash light circuit, does not generate ANY heat to the plugs. What causes the "heat", as you put it, is a signal directly from the PCM, to the GPCM, then to the plugs (glow plug activation is an independent circuit path from the dash light circuit). I am not talking about a plug getting red when it is turned on, lol ............