Charging System? Computer? HELP??

[94Z71]

911?? My truck is broke now!! My 94 Z71 is sick. Two weeks ago, my battery light came on, volt meter showed 9-10 volts. I replaced the alternator and everything was fine. One week later, I noticed that my dash lights were dim. No battery light this time, but volts were at 9-10. Proceeded to limp my truck to work without light, blower, or anything else turned on, barely made it, volts below 9, service engine light on, engine barely running, shut truck off, would not re-crank. One hour later after daylight, checked all alternator wiring, battery wiring, found no problems. Tried to start and it did, but with volt meter again at around 9-10 volts. Assumed the re-manufactured alternator was bad, replaced it during work, but after replaced, still only 9-10 volts. Attempted to drive home but did not make it(about 5-6 miles). Engine cutting out. Thank goodness for cell phones. About two hours later(after dinner out), had to jump start engine, drove another 4-5 miles to another parking lot (1 mile short of my house), engine cutting out, no power, etc. The next morning, jump started truck and barely made it to my house.
Presently, I have my trickle charger hooked up, but have not began any troubleshooting. I plan on starting with checking all battery cable, starter cables,checking battery water, checking alternator output, etc, but I am thinking a little bit that the computer in my truck maybe has gone south. I have never had any problems like this with this truck. It has 214 K on the ODO, but I have only had the truck since 188 K, so I don't know what has been replaced before that. The battery is only about 7 months old, alternator brand new, recent tune up. One idea is a bad cell in the battery? Have any of you had similar problems with your truck? When an engine control computer goes out, will it give these symptoms? Where is the computer and is there a way to test it? Any and all help is greatly appreciated! As I begin my troubleshooting, I will post my results. THANK YOU!!!!

[Ford_DOC]

is the Voltage Regulator internal to the Alternator. If not try replacing it. Hope you find the problem!

[94Z71]

The voltage regulator is internal. I dove into my Haynes book it there are two fuseable links in th main 10 gage wire from the alt to the battery. I'm gonna start there. There doesn't appear to be any connectionm between the computer and the charging system, so hopefully this will be simple. Any one else have any ideas? THANKS!!!

[Ford4x4Chik27]

I'd say find a mechanic friend and run the codes. That helps immensely. What type of battery are you runnin? I doubt that it's the battery but if it's bad it'll assist in whatever is goin wrong. Please keep us updated on how your search goes! Good luck!

[94Z71]

OK...ALL IS WELL . Got up early this morning. Checked all battery, alternator, starter connections. Seemed all OK except for some corrosion oozing down the positive cable from the battery. With my Fluke meter, checked the continuity at both ends of 8 gage alternator to battery wire. Had conductivity (did not check resistance of this wire). Jump started the truck this morning. Checked the voltage at the alternator - 14 volts. Checked the voltage at the battery - 9 volts. Started to think it was the battery. Started probing around where the 8 gage wire connected to the positive battery cable (where the corrosion is) - still 9 volts, but noticed this wire was hot. Wiggled the wire and heard wierd noise from alternator. Gave this wire a good hard wiggle and bam, 14 volts at the battery now .

Determined that noise was the alternator having a load put to it, because this wire was penetrated with current robbing corrosion. Wire is about 20" long and after stripping the insulation off of it I found that the corrosion had crept through the wire strands about 10" onthe way to the alternator. Proceeded to replace entire wire (soldered connectoins & heat shrink tubing) and for the first time since I have owned this truck (2 1/2 years), I now have 14 volts at the dash volt meter. Apparently battery acid has been eating away at this wire for a long time and finally got bad enough that it wouldn't allow current through it at all. Believe me, there was very little evidence of any corrosion near the battery as I try to keep these connections clean. I intend on replacing both battery cables very soon, as I am guessing that the same thing is happening to these wires.

I appreciate those who replied. Hopefully this may help others down the rode who have a similar experience.

[Ford4x4Chik27]

Awsome!!!!! Glad you got it fixed!! *thumbsup*

[DodgeChick]

Glad you got it figured out