battery/charge message every 10-12 minutes after reset; any clues? Also, pulls P0620 code

[ScubaDave1944]

Similar, but different to some other postings, so I'm adding it to the list. The saga began a year ago and with little respite, continues on today. A year ago, July 2021, my recently acquired '08 EB Explorer 4.0L bought with 154K miles before me had the Battery/Charge Error message illuminate for the first time I knew of.

I was returning to NC from a trip to NJ when the vehicle started acting up in the middle of a heavy rain storm only about 3/4 of the way home. Along with the light, the engine started losing power and the tranny started to miss smooth gear changes. I found a NAPA store near where I was and stopped to ask for them to read codes and suggest a fix. I don't recall all the codes for back then, but it included the P0620 and I was told I needed a new Alternator. After I changed it twice with units in their stock, they finally had a "new" MotorCraft unit delivered and I installed the third one still with it raining all around me, but it finally started delivering a strong charge. So we made it home, very late, but safely. Soon after returning, I decided to install a new battery, as well.

For a short while, it seemed all was well again, but then the message light started up again. And, then the tranny started acting up again with rough shifting. I was puzzled and stumped as to what was going on, so I took it to the ASE Certified mechanic my wife used for her car. He diagnosed the problem as a tranny problem that required a new/remanufactured unit be installed. Much as it hurt, I went ahead and had one found and installed. It required three weeks (due to parts, solenoid pak, being in short supply then) as well as two additional visits to replace that part again after the tranny acted up again shortly after i got the vehicle back.

Then, the message light started acting up again and the P0620 code came out again. After working on just that problem, the mechanic said he'd solved the problem by changing out the pigtail sensor wire to the Alternator. He twisted the wire to the one in the harness and covered it with heat-shrink tubing. In any event, we seemed good and even used the car for a Xmas trip to Boston and back to NC without any problems, as well as several other trips of several hundred miles without incident - though we kept our fingers crossed each time.

Fast forward to the Spring of this year and the Battery/Charge message started to return again. We took another trip to NJ and got caught in a heavy rainstorm just south of the first time's problem site on the way home. Shortly after the storm passed through our area, the car started to act up by losing power and having the message light indicate a problem. We hobbled along the Interstate at about 35 mph until I decided it was too dangerous for us to be there. We exited and took a back road for a while continuing to have little to no power, but trying to get somewhere that a tow vehicle might find us before calling it quits. We finally got the the highway we'd normally turn onto from the Interstate and as we went up the on ramp, the power returned and we ran OK, but with a message light, the rest of the way home. Again, the P0620 code was a part of the readouts. In addition, we had lots of misfires and related codes. I wound up picking up the parts and replacing the plugs, wires and coil and getting the car consistently running well - except for the message light with the P0620 code.

Now, I have centered my analysis to the charging circuit again and checked voltages and wiring related. Voltages were at 14.05 at both the Alternator post and at the battery with only about .02v differential, I figured the Alternator was likely OK. But in working around, I found that my battery cable to the battery from the Fuse Block bus was severely corroded through two slits in the covering. So, I got a repair piece for that cable and then cleaned all connections and added an anti-corrosive coating to the connections. I also got replacement voltage regulators for the Alternator, trying two different ones to see it=f there was any change in conditions. None, though one of them only gives 13.8v, but still about the same on both ends. Finally, I took the pigtail off that the ASE mech used and soldiered on a new pigtail; still no change.

This morning I went back to the Car Sales where I bought the vehicle and asked them to remove their GPS tracking device that I never returned to have removed since I paid off the purchase; they were some distance form me and I figured it shouldn't interfere, but was having second thoughts, now. But, it's removal didn't change conditions, either.

The Technical Manual for this vehicle indicates that the problem probably lies in the C2280E SJB (Smart Junction Box). This SJB is actually the Cabin Fuse box and circuit assembly which has connections from around the vehicle and senses voltage differences (for one) that indicate problems and can bring up that light. I found nothing untoward in the five connectors, A-E. on the box, but the problem could be inside it. However, the JCB and the fuses are up under the dash in an area where even and average size person can barely contort themselves to deal with. Also, I understand they are not cheap either. So, Im looking for alternative ideas.

The message light comes up about every 10-12 minutes after each reset. Is there something that times that interval? Is there something else I've missed? Any ideas, at all??

Despite all this, I've managed to get 25K additional miles on the vehicle and it's at 179.5K right now.


Appreciate any thoughts. - DaveW

 

[Fix4Dirt]

Similar, but different to some other postings, so I'm adding it to the list. The saga began a year ago and with little respite, continues on today. A year ago, July 2021, my recently acquired '08 EB Explorer 4.0L bought with 154K miles before me had the Battery/Charge Error message illuminate for the first time I knew of.

I was returning to NC from a trip to NJ when the vehicle started acting up in the middle of a heavy rain storm only about 3/4 of the way home. Along with the light, the engine started losing power and the tranny started to miss smooth gear changes. I found a NAPA store near where I was and stopped to ask for them to read codes and suggest a fix. I don't recall all the codes for back then, but it included the P0620 and I was told I needed a new Alternator. After I changed it twice with units in their stock, they finally had a "new" MotorCraft unit delivered and I installed the third one still with it raining all around me, but it finally started delivering a strong charge. So we made it home, very late, but safely. Soon after returning, I decided to install a new battery, as well.

For a short while, it seemed all was well again, but then the message light started up again. And, then the tranny started acting up again with rough shifting. I was puzzled and stumped as to what was going on, so I took it to the ASE Certified mechanic my wife used for her car. He diagnosed the problem as a tranny problem that required a new/remanufactured unit be installed. Much as it hurt, I went ahead and had one found and installed. It required three weeks (due to parts, solenoid pak, being in short supply then) as well as two additional visits to replace that part again after the tranny acted up again shortly after i got the vehicle back.

Then, the message light started acting up again and the P0620 code came out again. After working on just that problem, the mechanic said he'd solved the problem by changing out the pigtail sensor wire to the Alternator. He twisted the wire to the one in the harness and covered it with heat-shrink tubing. In any event, we seemed good and even used the car for a Xmas trip to Boston and back to NC without any problems, as well as several other trips of several hundred miles without incident - though we kept our fingers crossed each time.

Fast forward to the Spring of this year and the Battery/Charge message started to return again. We took another trip to NJ and got caught in a heavy rainstorm just south of the first time's problem site on the way home. Shortly after the storm passed through our area, the car started to act up by losing power and having the message light indicate a problem. We hobbled along the Interstate at about 35 mph until I decided it was too dangerous for us to be there. We exited and took a back road for a while continuing to have little to no power, but trying to get somewhere that a tow vehicle might find us before calling it quits. We finally got the the highway we'd normally turn onto from the Interstate and as we went up the on ramp, the power returned and we ran OK, but with a message light, the rest of the way home. Again, the P0620 code was a part of the readouts. In addition, we had lots of misfires and related codes. I wound up picking up the parts and replacing the plugs, wires and coil and getting the car consistently running well - except for the message light with the P0620 code.

Now, I have centered my analysis to the charging circuit again and checked voltages and wiring related. Voltages were at 14.05 at both the Alternator post and at the battery with only about .02v differential, I figured the Alternator was likely OK. But in working around, I found that my battery cable to the battery from the Fuse Block bus was severely corroded through two slits in the covering. So, I got a repair piece for that cable and then cleaned all connections and added an anti-corrosive coating to the connections. I also got replacement voltage regulators for the Alternator, trying two different ones to see it=f there was any change in conditions. None, though one of them only gives 13.8v, but still about the same on both ends. Finally, I took the pigtail off that the ASE mech used and soldiered on a new pigtail; still no change.

This morning I went back to the Car Sales where I bought the vehicle and asked them to remove their GPS tracking device that I never returned to have removed since I paid off the purchase; they were some distance form me and I figured it shouldn't interfere, but was having second thoughts, now. But, it's removal didn't change conditions, either.

The Technical Manual for this vehicle indicates that the problem probably lies in the C2280E SJB (Smart Junction Box). This SJB is actually the Cabin Fuse box and circuit assembly which has connections from around the vehicle and senses voltage differences (for one) that indicate problems and can bring up that light. I found nothing untoward in the five connectors, A-E. on the box, but the problem could be inside it. However, the JCB and the fuses are up under the dash in an area where even and average size person can barely contort themselves to deal with. Also, I understand they are not cheap either. So, Im looking for alternative ideas.

The message light comes up about every 10-12 minutes after each reset. Is there something that times that interval? Is there something else I've missed? Any ideas, at all??

Despite all this, I've managed to get 25K additional miles on the vehicle and it's at 179.5K right now.


Appreciate any thoughts. - DaveW

i dont see how the trans would cause a p0620, its a charging issue. or at least that being their go to fix, given the cost hows the wiring from the alt? thats the only "old" part of the system. check the ground of the alt. does it take longer to start?

can you test the wiring from alt? that would be where i would start.

imo its not timed so to speak its just more it reaches a level of depletion in which iy determines its time to flash the check charging light, or it could be that sometimes for example to set off a code it will take a short drive usually. could he one or the other or both

good luck!

 

[ScubaDave1944]

Thanks for reading my post.

I agree, the P0620 is a charge issue. I think it can cause a tranny issue when the voltage drops too far for the on board computer controls to work right, maybe. But my voltage, except my first time has stayed up in the 13v range when I measured it. Of course it might drop under load and I can’t measure that in real-time.

 

[Fix4Dirt]

Thanks for reading my post.

I agree, the P0620 is a charge issue. I think it can cause a tranny issue when the voltage drops too far for the on board computer controls to work right, maybe. But my voltage, except my first time has stayed up in the 13v range when I measured it. Of course it might drop under load and I can’t measure that in real-time.

yes, i agree if it drops too low, but that wouldnt be my first change.

 

[ScubaDave1944]

Battery/Charging - Alternator Idiot Light Solution

Well, it's solved and it's NOT a bad alternator or regujlator! After watching a few more YouTube segments that danced around the P0620 issue from a control circuit perspective, I got enough knowledge to understand how that charging system actually works and eventually pointed me to the area that could cause the problem and explained why I was lucky to not ruin the battery in the process. Also, it explained why my mechanic 'found and fixed' the problem, but it returned after a while. So, what's the answer, a faulty connection.

There are only three connectors with a total of 5 wires to the Gen 4 alternator:

1) the battery lead (#4 wire) to the starter solenoid (and on to the engine fuse panel and battery for charging).

2) a sensing lead to the the Smart Junction Box (SBJ) that hides under the dash over the passenger compartment fuse box in front of the driver, to sense the alternator output voltage to compare the voltage to the battery cable voltage,

3) and two control leads to the voltage regulator (VR) from the powertrain control module (PCM) plus one more:

3a) one to get messages from the PCM

3b) one to tell the PCM what the VR is doing in response to the command, raising or reducing the voltage output,

3c) and one to sense the actual voltage delivered to the battery and report it to the SMB to trigger the Battery/Charging error Idiot Light or Message if it isn’t within differential specs. There is always a small difference, but it should be no more than around 0.5v+-.

1 & 2 are easy to locate and check voltage values and, while #2 can get or seem to get a bit loose, it’s can be seen easily and doesn’t usually cause problems. #3 is a fairly easy one to remove, but checking the leads in realtime is more difficult; you need to watch the loose test wires and shirt sleeves from getting entangled with the fan. The connector needs to be installed and you use a pin or similar down along side the wire to the terminal itself to connect test leads to it from and oscilloscope or similar device to view the information.

I have a digital voltmeter, but no oscilloscope. But, once I understood the principles of this circuit it made me inspect the plug and, lo and behold, I saw the center terminal was pushed up into the casing, not making contact, and wasn’t reporting what was happening properly. Luckily, the alternator went into safety mode - just charging and a reduced rate, since it didn’t know what it should be according to the PCM. So, my year old battery reads only Fair with a hydrometer, now, but it’s still serviceable.

After pushing the errant pin back down in place, the voltage delivered to the battery settled on 14.4+-v and has remained steady in that range. Also, the Idiot light message no longer comes up. I reset the trouble codes and they have stayed cleared for several days now, vs the earlier times when it would return with in a few minutes of startup. So,, I’m stoked that it is finally FIXED! I have noticed as well that several strange problems, bluetooth connected Sync system would hiccup and restart my audio repeatedly back a few paragraphs and no other systems are reporting problems as they had been, either. I was seeing EGR failure and Throttle Body errors coming up every so often when the alternator wasn’t controlled properly.

Hope this is of use with others along the way.

Thanks for suggestions of various folks along the way.


DaveW

 

[ScubaDave1944]

Oh the every 10 mins timing apparently has to do with the alternator safety mode and the way it rechecks the condition to see if it is still bad. Since I kept resetting it each occurrence, it send another instruction downstream to the alternator multiple times until a threshold of no response was reached and then it would turn the trouble light back on.

DaveW

 

[D Hook]

This is great to know. Thanks for the follow up!