The crank sensor can cause a no-charge condition? Really??? This is the first I have heard of that one..... failed crank sensor causes an engine miss, or, for it to not run at all. I suppose, if it isn't running, the alternator won't be charging the battery......

Got any links to support that theory?

I suppose, you could charge the battery up really good, drive the truck to the parts store, and have them put a load tester on it..... though, if the alt isn't charging, that test will only confirm that, won't tell ya WHY it isn't charging.....

 

I highly doubt replacing the crank sensor is going to fix any charging problems. Of course not running to begin with is a different story.

 

We're talking some parts flinger at Advance Auto. Probably some kid who wouldn't know a cam from a complete set of V10 muffler bearings.

 

Just verifying the note that you took your starter to have it tested? I have never seen a bad starter cause a truck to stop running only not starting. The alternator HAS to be tested under load to verify if it is bad or not. If you cannot drive the truck to a parts store to have it checked replace the alternator and ensure that your battery is fully charged. If that does not fix it then return the alternator and get your money back. But for the love of vehicles, don't trust the parts store guys.

 

CORRECTION: I had the alternaor "tested" at Advance, not the starter. Am I hearing it right that the store bench testers do not put enough load on the alternator to properly test them? Is it possible that it tested good at the store but isn't strong enough to work ina real world situation?
When the guy had it on the tester, it sounded good - no bearing scraping or anything like that, but that's moot if the coil is open.

I've read the following note posted about this vehicle on Advance's alternator part description. I'm sure I read it elsewhere, but I'm not sure.
"CAUTION: Pulley Change May Be Required; INSTALLATION ALERT! An inoperative crank sensor may cause a "no charge" condition, especially if the vehicles tachometer, air conditioning, and/or cruise control is malfunctioning.; See Tech Tip # 642"

Adam

 

It's a little embarassing, but I just learned that a vehicle can display fault codes without an external computer.

http://dodgeram.org/tech/gas/Trouble/pcm_fault_code.htm

Adam

 

It's not the best way (nor does it tell you much). But, if you have the engine running and the alternator is charging, it will turn the pulley into an electromagnet.

Use the tip of a screwdriver (or anything metal), and put it on the inside of the pulley. If it sticks, it's charging, if not...well, it's not.

This is slightly dangerous, be careful. It's one of those, "side of the road" type diagnosis. Learned it from a tech I used to work with from Kenya.

 

DK, thanks for the roadside tip.

I had the 2500 towed home today. I charged the battery and started it. After letting it run for a few minutes, I connected a volt meter to the alternator and measured 13V at idle and 14V at around 2,000 RPM. I then drove around a bit to see if the problem would occur again and also generate an error code, but all that I got was error 32, which reads: Short or open in the EGR solenoid circuit. Check for loose, broken, or shorted wire in the EGR valve wiring and connectors. Possible air fuel ratio imbalance not detected during diagnosis.

While driving, the battery meter occasionally dipped down to 12-13V but then returned to 14V, all while at nearly the same RPM. I don't know if that is relevant.

Adam

 

If there is a short as indicated, it could suck voltage down while driving.

Also the alternator magnet trick - the core of the alternator magnetizes. It is safer to attempt this on the back end of the alternator - not the front end with rotating parts.

 

Thanks for the safety tip, Gdstock.

I noticed that the air conditioner compressor kicks on and off for a while after the engine starts. That is, there are two wheels on the compressor - one is always in motion as the belt is turning and there is a wheel within that wheel that turns occasionally and is accompanied by the sound of the compressor kicking on, though the AC is turned off.

Adam