Help! Problem before trip - Battery idiot light on

[ossaracer766]

I have a (new to me) 1998 E-350 extended, with 7.3 PSD motor. Converted Oil company lab rig. Hi-top, cool interior with aluminum cabinets, etc. Also has a third battery and 1000W power inverter mounted.

Have had the van for 4 months, LOVE it!! the 1 ton suspension and PSD power are fantastic, I use it to pull trailer full of racing motorcycles all over the USA. 3.55 gears are awesome also....great freeeway rolls along at 75mph with trailer like nothing!

Well, just before my Bike Week trip, today it showed battery idiot light. Was on for about 30 minutes of my trip, then went away, I could tell the laights went brighter when it went out. A clue is my XM reciever seems to come on once voltage comes up, as in the mornings the first 30 seconds as van starts no XM reciever, then it comes on, seems to be as voltage comes up?? While the idiot light was on, my XM was inoperative no power to recevier, so something voltage related??????

The van also has what seems to be extra electronic voltager regulator monuted right above auto trans check dipstick...IS this an indication my (single but very heavy duty) alternator is going, or voltage reg maybe, or just battery connections, etc?? Both the main batterys are about a year old and seem OK...(I got to check water levels now) slight corrosion on the smaller positive conneciotns but minor. Help, Ideas, thoughts???? troubelshooting?? I am getitng ready to pull trailer and do like 2000 mile trip!! Wished I d sent away for that owenrs manual now...I dont even have the fuse box legend to check as no owenrs manual yet...aarrgghh Thank you for any help here!! Terry

[nukiepoo]

To see if your alternator is charging properly, get a digital voltmeter and measure the battery voltage while the engine is not running. It should be between 12 & 13 volts if the batteries are not dead.

Next, start the engine and remeasure the battery voltage. It should be 3 to 4 volts higher if the alternator's charging. If you see no change, something is wrong with your charging system. It could be regulator, brushes, diodes, alt windings, connections, etc. If I would hazard I guess, from what you described, I'd suspect brushes or loose connections. Best of luck

[sixiron]

My first guess is that you have a weak battery ...

Why?

When you first start your van the glow plugs are cycling and drawing a large amount of current...hence no XM radio until the glow plugs have cycled-out and there is the "proper" amount of current...

Also the battery light stays on until you've charged-up after initial start-up

And that voltage regulator above the trans dip stick is a NO TOUCH...its a wiring connector between the engine harness and the CPU...you can move it around for servicing ..

my .02 check your batteries and alt...but I bet you have a weak battery somewhere and these PSD's do work batteries hard...

bd

[whotnow]

FYI. The alt. Does not charge fully the batteries until the glow plugs turn off! The glow plugs are only rated at 12volts.

They could have installed a battery isolater for the third battery. This way if you run down the inverter battery(Third Battery), You wont kill the truck's starting batteries and be stranded.

With as many miles as the truck has on it plus the accessories that have been used in the past, i would say you are at the end of life of the alt. Buy a new one. [img]/ubbthreads/images/graemlins/smokin.gif[/img]