Alternaror problem?
 

2001 PSD with single alternator is throwing Dual upper alt and dual lower alt codes. What's this all about?
Also is there a upper voltage reading with alternator charging that would indicate a failed alternator? I have a low cost volt meter plugged into the cigar lighter socket that reads 14.8 to 15 volts after the Glow Plugs turn off. I will chack the voltage reading with a good DVM, but this seems high to me.
Thanks for any replies

Post the codes and I'll look them up.

What does your dash gauge tell you? Is it in the "normal" range? In my limited experience, batteries and alternators are rarely bad if you're reading voltage a little high. If I make a mental estimate of where my battery gauge is reading given its position between the 12V and 18V marks, I'd say it is about 15 volts when running.

The volts should be right around 13 -14 with the truck running. If your gauge dosen't have numbers on it ( mine dosen't) get a voltage meter. Got mine for about 10 bucks. Real handy for other stuff too. Just touch each battery post with the leads from the tester to get the reading.

Sorry for the delay.

I have 2 different issues:
1. I have an Evolution Programmer that reads codes. I pulled 2 codes, one for upper dual alternator high, the other was for lower dual alternator high. I cleared the codes and did not right them down. The thing is, I do not have dual alternators.
2. I have a digital plug in volt meter (plugs into the cigar lighter). It is reading up to 15 volts. This seems high to me.

15 volts doesn't sound terribly high to me... The alternator I put in my 2000 Ranger was rated from the manf. at 14.7 volts... Electrical problems are tricky... If you really want to know, most auto parts stores have alternator testers for in and out of vehicle. The ones that have at our Advance in town are really nice, all computerized, and can even print out load vs. rpm, volts vs. load, and a host of other stuff...

Thanks to all for the replys.