DieselD Posted August 16, 2007 Share Posted August 16, 2007 06 F350 6.0, APS electrical service truck. check engine light on with P0620 P0623 P1149 orginal batterys at 25,055 miles. charging at 72amp 13.5v at idle and running all lights, 4 kc lights, beacons, flashers, radios, etc. At high idle it pegs my Vat 40 over 100amp and about 14 volts. according to as built it should have a 110amp alt so this all seems correct. p1149 is a generator 2 fault, this truck is only a single alternator truck. They are countiuous codes but have been having issues for months. They have taken it to several dealers to throw parts at it including a pcm and nothing has fixed it. my question is why am I seeing a gen 2 fault when there is not one? I also see a gen2 fault pid as well. the previous dealer did a blank path when they replaced the pcm about a month ago. anyone have any issues like this? Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted August 16, 2007 Share Posted August 16, 2007 Is the truck a "used to have" dual alternators? If so, Q-91 on the fleet.ford site might help.... Another thing you might check... I think I thought I maybe might have seen a dual/single generator "switch" in "programmable parameters"... at least I think I might have seen it... Quote Link to comment Share on other sites More sharing options...
Brad Clayton Posted August 16, 2007 Share Posted August 16, 2007 All those codes are for dual generators. I'm wondering if there is some mismatched parts going on. I looked at the wiring diagram and you can definetly trace the wiring back to the PCM and cluster to see if it was ariginally equipped with one or two, and the upper and single generators are interchangable but not the lower one. I've seen people cross the wires in the regulator connector, why they would do this I don't know. They usually won't charge when this happens, but you say you're charging good so I doubt that's the case. Sounds like you got a real winner, wish I could say I ran into one like it with a fix. Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted August 16, 2007 Share Posted August 16, 2007 What's the deal with the high charge rate? I'd find and fix that first. Excessive parasitic draw? It should be under 50ma (.050A), I commonly measure 15-20ma on Fords. A normal truck will have an amp spike on startup of 60-100amps for under a minute, and will settle down to a charge rate of under 20 amps within 1-2 minutes. Many trucks will settle down to 5 amps or less in a minute or two, as long as the bats are good and there's no slow drain. These are all measured at the battery, not alt output. You're measuring your 100A at the alt, right? What do you measure going into the bats? In my notes I have: The PCM automatically recognizes single/dual alt's by looking at voltages on the harness. It may forget a dual alt setup if the battery goes dead, but will recognize it after 3 key cycles. How about a grounded Gen 2 I-line? Even if the Gen2 is not there, maybe the wire is. If the PCM decides to feed it's normal ref V down that line and it's rubbed to ground, you're going to get a Gen2 code. Gen's pull the I-line to ground to relay a fault from the Gen (regulator, actually) to the PCM. I did have a big time ghost Gen code from a rubbed harness on a 6.0 that caused a bunch of parts to be replaced. My notes have the I-line at VBAT unhooked, and 1-3V connected. Ford uses “generations” to label alternators. They went from 3-G (3rd Gen) to 4-G and then to 6-G, and back to 3-G. Could your truck have the wrong generation of alternator? More stuff from my notes and class: The PCM can become confused and think the truck is a single alternator system if one alternator is unhooked and the key is turned on. Disconnect the batteries and turn on the lights to drain capacitors and the PCM will “relearn” upon reconnecting automatically. The PCM will also automatically learn dual alternators are present after 3 key on/run cycles by watching pinout voltages. I-line may go dead while running, effectively shutting down one alternator. This is a normal occurrence in strategy. PCM uses IAT to infer battery temperature for charging voltage. There may be one dead alternator, and BAT or MIL light may not light up. There will be codes, though. This info was proofread by one of the best electrical guys in our industry. If anyone sees any typos or wrong info, please let me know. Good Luck! Quote Link to comment Share on other sites More sharing options...
Brad Clayton Posted August 16, 2007 Share Posted August 16, 2007 I've got a body off a '05 and I looked at the PCM connector, all the wiring is there for a dual setup even though mine is a single. My idea is a wash. Sounds like Bruce is all over the fix. Very informative post to so the least. Quote Link to comment Share on other sites More sharing options...
OHNO60 Posted August 17, 2007 Share Posted August 17, 2007 YIKES /forums/images/%%GRAEMLIN_URL%%/puke.gif Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted August 17, 2007 Share Posted August 17, 2007 Excessive parasitic draw? It should be under 50ma (.050A), I commonly measure 15-20ma on Fords. In my notes I have: How about a grounded Gen 2 I-line? Even if the Gen2 is not there, maybe the wire is. If the PCM decides to feed it's normal ref V down that line and it's rubbed to ground, you're going to get a Gen2 code. Gen's pull the I-line to ground to relay a fault from the Gen (regulator, actually) to the PCM. Good Luck! Clarification: Parasitic of 15-20ma is AFTER all of the modules got to sleep, which takes 30-45 minutes. I've done this test a bunch of times on a variety of Fords in my electrical classes. It's kind of cool to hook a DVOM in series and physically watch the modules go to sleep. The parasitic will commonly start out at .5-.7a and drop down in 4-5 steps to 20ma after a half hour. When they have a theft light on the dash that blinks the draw jumps up to 25-30ma. It means a bunch to the students to demonstrate this.... Emphasis- Gen's pull the I-line to ground to relay a fault from the Gen (regulator, actually) to the PCM. I'd find that Gen2 I-line and see if it exists on this truck. If it does, I'd snip it at the PCM and go for a road test.... Good Luck! I happen to have a good pic of it. See if this wire exists..... Quote Link to comment Share on other sites More sharing options...
DieselD Posted August 17, 2007 Author Share Posted August 17, 2007 Bruce your the man! I hope to get time to work on this turd today. They have me tearing down a torqshift out of an LCF /forums/images/%%GRAEMLIN_URL%%/banghead.gif I try and tell them Im an engine guy not trany guy but I get the respone of "well you have your certs" This is the first one Ive done so we will see what I can screw up! anyway back on topic. I did a little research and I also saw that everything is there for a gen2. There is a plug on the right side next to the battery that loops the I line back in to the harness. this is the plug that would plug into the gen 2 harness if it had one. I drove it about 30miles yesterday and got the P0620 and P0623 to come back but not batt light or Mil. The MIL is coming on due to the P1149 code. I swapped gens from another truck to see what happens. I will post up what I find Quote Link to comment Share on other sites More sharing options...
DieselD Posted August 20, 2007 Author Share Posted August 20, 2007 swapped gens and still got the P0620 and p0623 to come back but no P1149. I double checked my charge output and its inline with your specs bruce. It will drop down around the 20amp range after a couple minutes of idle time. I checked at both the gen and batterys and it was a little higher at the gen like it should be. no worrys there. I disconnected cicuit 1185, yellow pin 4 of the processor like bruce suggested and drove it. I have yet to get any type of codes back so far. I plan to drive it further to see what happens. crossing my fingers /forums/images/%%GRAEMLIN_URL%%/icon_crazy.gif Im about to /forums/images/%%GRAEMLIN_URL%%/flamethrower.gif this truck! Quote Link to comment Share on other sites More sharing options...
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