2003 EB Charging System Warning/Battery Icon On

[Transporter]

NOTE: If Mods find a better place for this feel free to move it. I went though a bunch of the Electrical Threads and mine is kind of different.

Problem: Battery reads 13.9 volts at start of week. Charging System Warning then Battery Icon come on. Both go back off while driving. I have an App that reads battery voltage and it did drop down to 12.5 while the light was on, then the Icon went off and App shows 13.5. Next trip trucks starts and runs fine, App shows good voltage no warnings or Battery Icon. Half way through next drive, App shows voltage at 13.5 then I get the warning, then Battery Icon, then App starts reading 11.17, then back to 13.5, then 13.7 and warning and Icon go away. This repeats until yesterday.

I go out to start the Expy and it will not start. I check the battery with DMM and it shows 10.8 volts. Take out battery and go to Auto Zone and they give me a new battery as I have 5 weeks left on my total free replacement before the 2 year pro-rated part starts. Everything seems fine now. App shows 13.9 while driving.

This morning, drive to the Airport and everything is fine. Stop at a hotel to use the restroom before doing the loops at the airport to pick up the better half who's flight is coming in. App starts showing 12.5 then goes purple meaning it is below 12 volts for it is showing 11.5 and the warning and Icon both go off. Pick up better half, App is showing 11.17 again. I have been home an hour and the truck will start but the voltage on the DMM is showing 12.5 at rest. Which means it isn't charging. Warning and Icon were on at start-up this time.

Lastly during all of this the Alternator Meter on the upper right of the instrument cluster stays in the good range for charging. Does this tell us anything. OBDII is not showing any codes. Is the dash meter just to tell if the Alternator is charging but not that the charging system itself is working properly?

Where should I start troubleshooting this to start eliminating what it is not so I can find what it is? One side note, with my last battery change 3 years ago, I had to do the positive terminal mode has the terminal was completely fused together and I could not get it apart. So I have a battery post clamp with a vertical bolt to put the three cables on including the one that used to have the used to have the bolt as part of the connector that the other two went one. The old cable that used to have the bolt now has a hole in the spade to go over the bolt on the new battery lug.

Thoughts and suggestions?
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[Hamfisted]

New Motorcraft alternator .....


https://www.rockauto.com/en/catalog...411119,electrical,alternator+/+generator,2412

 

[Plati]

For what its worth …. I put a new Autocraft GOLD 850 cca battery in my 2003 Expy in Winter 2018. I measured the initial resting voltage (engine off) to be 12.3V. The voltage would drop to 9.9 (briefly) while starting. Voltage would go to 14.5 while running with little to no load (headlights etc).

I thought this was low so I trickle charged it fully. At the end of trickle charging the voltage was 13.5V. I let the whole thing rest for 12 hours and voltage dropped to 12.7 with no engine running. Seems normal.

I measured the voltage while starting it would drop to 10.6V briefly.
Then I started engine and turned on headlights and fans any anything I could think of and the voltage was 14.4V. All good.

 

[Transporter]

For what its worth …. I put a new Autocraft GOLD 850 cca battery in my 2003 Expy in Winter 2018. I measured the initial resting voltage (engine off) to be 12.3V. The voltage would drop to 9.9 (briefly) while starting. Voltage would go to 14.5 while running with little to no load (headlights etc).

I thought this was low so I trickle charged it fully. At the end of trickle charging the voltage was 13.5V. I let the whole thing rest for 12 hours and voltage dropped to 12.7 with no engine running. Seems normal.

I measured the voltage while starting it would drop to 10.6V briefly.
Then I started engine and turned on headlights and fans any anything I could think of and the voltage was 14.4V. All good.

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Correct because with the engine running and the alternator functioning and the PCM allowing it to charge, the alternator/charging system not the battery is reading 14.4VDC. Once you start your vehicle and your PCM and Alternator are working, one can no longer read battery voltage. Battery voltage can only be taken when the motor is not turning a working Alternator controlled by a PCM. I should have been more specific that my App is reading the Vehicle Voltage and not specifically the battery voltage. Yes those two readings can be the same but only when the Alternator/PCM are not actively running or by chance happen to match. Before the vehicle is started, the App is reading the battery voltage, but once the vehicle is started the App is reading the vehicle voltage which will only match the battery voltage under two circumstances 1) the Alternator/PCM are dead or have a wiring issue so it can only read the battery 2) the charging system just so happens to momentarily happen to match the actual battery voltage IE charging system voltage is not actual battery voltage 99% of the time.

My biggest question is that my Alternator/Battery meter is in the Green/Good area IE not high for over charge or low for not charging, yet I have a vehicle voltage of 11.17 showing on the App which to me would say the Alternator is working but the battery isn't getting charged, so does that mean it is a PCM issue? The Meter Reading and the Battery Icon reading are in conflict with each other. Ford wants $850 to put a new Motorccraft Alternator and serpentine belt in. If it is not the Alternator, I will go nuts if I have them do that.

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[riphip]

If you can replace a battery, you should be able to replace a belt & alternator. Hamfisted posted a link to Rockauto for a 110 amp replacement. Belt would be from same site (get the Motorcraft). Very good prices for both. Should have by Monday/Tuesday. Use code: 1673782C22D952 for 5% off.
You can get sooner for more$ shipping

 

[stamp11127]

Hey Transporter, with all the great advice you have been given so far I would prove the alternator has failed before tossing parts at it.

 

[99WhiteC5Coupe]

I would closely examine and evaluate the positive cable that has been modified. Examine the connectors, fasteners, and cable for any signs of corrosion, or swelling of the plastic sheath, which indicates corrosion has migrated up the cable (which reduces the electric current and increases resistance).

 

[stamp11127]

Transporter I would measure charging voltage at the output stud and case ground and at the battery for accurate results. Apps are nice but may not show voltage drop in certain parts of the circuit.

What you are describing is an intermittent electrical fault. Those can be anywhere in the circuitry. Kill power to the field coil and that is all she wrote, same with a loose connection.

Some times you charge and some times you don't. Sometimes you feel like a nut, sometimes you don't....Almond Joy has nuts, Mounds don't. Don't you miss those commercials?

 

[Transporter]

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UPDATE: Thanks for all the suggestions as well as the URLs to find parts. And a special thanks to @stamp11127 for pushing suggestions. After ohming all the connections out, No Joy. Every single time I check the voltage it was showing voltage at the Alternator and when out on the Interstate over 70MPH the battery light would go out and the battery would charge.

So I ordered a Serpentine belt and new Alternator. I specifically asked for a Ford Alternator and they sent me an OEM substitute. The Alternator changed the battery as I had no more low voltage or morning cranking problems but the Battery Light stayed on even on the Interstate. So I had them send me what I paid for, light is now out. My advice, only buy a new Ford or Ford Reman Alternator for your Ford because it needs to talk to the PCM to work properly and not throw codes.

Thanks again guys. Ford down the street wanted $900 to replace the belt and Alternator. Belt and Alternator cost me $205 and took three hours to change the two (than another hour to remove and put the proper Alternator in).

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