[NAIRB]

I am currently working on a 2001 Ford Van that has charging system failure.

It is not the alternator, i've bolted 2 on it with and only have battery voltage.

I did put a fresh battery in it just to have a strong power source in it as the old battery was weak and OEM.

The vehicle has been acting up for a while, but I did find a broken battery end on the ground of the battery. It was barely touching the battery, but has been running around like this for a while.

I am getting juice to the charging post on the back of the alternator, so I am going to say that I don't think I have a fusible link or maxi fuse problem, but I'm no expert on this type of stuff, so I could be wrong.

I am at a loss as to where to start.

I though I might try checking for a blown fusible link, but since I seem to have continuity all the way from the charging post to the battery, I didin't think that was my problem.


Any ideas?

[docvette]

Doc here,

Did you try putting a volt ohm meter across the battery while it was running?
If so, was it at 14.4 volts? If not you could have a blown fuse link,feeding back into the battery.

However you say the continuity is good from it to the battery,so I 'd put that on the bottom of the list..

You didn't say how you determined you have a bad charging system...Is it dead the next day...or not picking up any charge after a jump start? Does it have a gauge or light..or both?

If it's dead the next day, after a full charge...I'd look for a system drain, by putting a meter between the Battery cable, and the battery post..If it shows more than 3 ma..you have a drain larger than the memory preset on the CD and keep~Alive on the confuser...Start pulling fuses until you get it down to around 3 ma..then, troubleshoot the last circuit..that's where your draw is going to be.

This could also Include a bad regulator..If external (not a Ford Guy, so I don't really know) it's probably Solid state, a plug in Epoxy brick...If that were crowbarred shut, could also impose a load just sitting...Also it can account for lack of charge back to the battery...a two fold problem.

If you have a gauge, and it's a shunt type, and isolated only to the charge system...and the gauge (shunt) was open, neither would work...

If you have a Charge light, does it come on when you just turn the key on? If not replace it...on SOME systems a defective charge light can disable a charge system...

Do you have (GM's Do..) a Choke light? and are you getting that? (or a buzzing like a mini~Shaver type sound) If so this is indicative of a field output problem...more specfic...Diode pack...

Don't rule out that the new Alternator may be defective...Tons of OBF's with that stuff...

Also, you may have a serious ground problem at the Alternator, Especially if it's mounted on an aluminum mount...If that mount is powder white, you may have Electrolysis going on and no ground...Run a 10 gauge wire fro the ground lug terminal or alternator mount bolt to your main ground..That will short term fix the problem...long term is pull the mount, water pressure or sandblast it , and the hardware, then apply a good amount of Aluminum wire coating to the hardware and reassemble...

Pull clean and tighten the battery cables and grounds ...no corrosion..

Post back after you read the running voltage at the battery, with what you have (gauge or lamp, regulator internal or external, Choke light or no..) and we can help you a little better..

Doc

[KULTULZ]

I am getting juice to the charging post on the back of the alternator, so I am going to say that I don't think I have a fusible link or maxi fuse problem, but I'm no expert on this type of stuff, so I could be wrong.

• By fresh battery, I assume it is new? And I am assuming both battery cables are now in good condition?
  
• Using a voltmeter, measure battery voltage with engine off (you may want to burn the headlamps for sixty seconds to take off the top charge...
  
• Start engine and again measure battery voltage. It should peak at approx. 14.5V Again measure with a draw...all lamps and accessories on. Did it stay constant or drop?
  
• The alternator circuit is fused (MAXI-FUSE...POWER DISTRIBUTION BOX) should be to right of air cleaner.
  
• You are going also going to have to measure alt. output compared to voltage received at the battery.
  
• If you have voltage at the alt. terminal with the key off, you have a defective alt.

-ALTERNATOR VOLTAGE DROP TEST-

[NAIRB]

I hate to admit it, but I really overlooked the obvious on this one.

The vehicle had been in another shop earlier in the morning. They had been working on the ac blower switch. Some genius decided to pull the fuse out of the fuse block for the alternator and put it in for the blower motor, then they let the customer go with battery only. This is what you get when a "mechanic" from a tire shop performs electrical repairs!

I would have spotted it sooner, but being that late model Fords don't give you identification on the fuse panel for each fuse, I had no way of knowing which fuse was which without tearing the wiring harness apart, or having the owner's manual (which was missing). The battery light did not come on which should have cued me in sooner as to what was happening.

Live and learn

Brian

[docvette]

Doc here,

Kewl!

One Nice thing about the infamous overlooked obvious....

It's usually Cheap and Easy to fix!

Thanks for posting back and letting us know...will help the next guy!

Glad to hear your back on the road!

Doc