[jmatt]

I've got a 01 5 speed and today I got a dead pedal and got the alternator checked and it has low voltage. Can this low voltage affect the tps to not let me get over 25 mph

 

[Clunk]

Not sure about the dead pedal but it's enough to not charge the batteries then they won't have power to start the engine.

 

[jmatt]

The batteries stay charged but read just under 12 volts. I know its suppost to have 14 so I didn't know if it was low enough to cause a low enough voltage to mess with the tps or why its doing it. I checked the battery terminals and one of the grounds was loose so I tightened it up and cleaned them off and it still has a dead pedal. First and second gear work fine but 3rd it stops and goes to an idle and won't let me drive faster then 25 mph

 

[pmccue]

codes?
A bad alternator can create electrical noise when a diode fails and this can interfere with other electrical devices. I have never heard of it actually causing what you are describing however. I would think you will have codes stored which will guide you to the source of your problem. Do the key trick and post up codes.

 

[jmatt]

Ill do it tomorrow. My smarty was reading a low voltage to the tps last week that's why I was wondering if it could cause that to happen. My buddy said that these trucks are very sensitive to low and high voltage.

 

[jmatt]

I ran the codes and got the 0463 and the 1693. Then I took it to oriellys and got the code ran up there and it said the ecm/pcm is bad or needs to be flashed. So I set the smarty back to stock and its fine now with no dead pedal but still runs at a little bit over 12 volts. Anybody got any other options to try

 

[pmccue]

I ran the codes and got the 0463 and the 1693. Then I took it to oriellys and got the code ran up there and it said the ecm/pcm is bad or needs to be flashed. So I set the smarty back to stock and its fine now with no dead pedal but still runs at a little bit over 12 volts. Anybody got any other options to try

there are no specific codes that say your ecm or pcm is bad unfortunately.

 

[jmatt]

The guy at oriellys hooked their obd up and it had a code. Don't remember which one it was but he looked it up and that's what it said. But I set the smarty up and set it to stock setttings and it has no dead pedal. Runs like it should with the exeption of the volts still reading at 12 instead of 14

 

[pmccue]

Operating you should see over 14 volts measured at the batteries. At 12 volts operating you could be causing all sorts of electrical issues. Get the alternator rebuilt or replaced then see where you stand with other stuff. Remove and bring both your batteries in for a free load testing at parts stores. You have to have proper charging electrical system or you will have problems.

 

[jmatt]

I got a new alternator and the voltage stayed the same. Maybe just a little over 12. But I unhooked the smarty and put it to the stock settings and the dead pedal is gone. Everything is right now exept the voltage is still low. It should be right at or under 14 shouldn't it

 

[Shainer]

I got a new alternator and the voltage stayed the same. Maybe just a little over 12. But I unhooked the smarty and put it to the stock settings and the dead pedal is gone. Everything is right now exept the voltage is still low. It should be right at or under 14 shouldn't it

You really should have kept that alternator. What you have now is a huge unknown that may last years, or a week.

If you disconnected the batteries when changing the alternator out you changed the APPS calibration. It is possible you have a dead spot in the APPS, but I wouldn't worry about that until you get your charging issue rectified.

In the future just pull the codes with your smarty and look them up on the web making sure it is Cummins specific.

 

[jmatt]

Well my smarty said that I had low voltage to the tps so I didn't know if that's what the dead spot was comeing from. Then the guy at oriellys tested the alternator and said it was bad do I changed it. It was charging and didn't kill nothing I was just getting low voltage readings so ifigured that's why it was saying that the tps had a low voltage

 

[pmccue]

starting to make sense, you had a code for the apps and dead pedal. sounds like its Timbo time.

 

[jmatt]

Well its gonna be that or ecm. I been reading symptoms of bad ecm and it sounds like it could be that to. I unhooked the battery do I need to calibrate the apps?

 

[TAKEN5875]

Read what jmatt said again carefully. I believe he said Low voltage TO the tps not coming from it. Correct? Good luck. My Bad ECM was giving all sorts of low and high voltage codes. All of this started from a bad alternator. And ended with an alternator, ECM, and new batteries

 

[jmatt]

I'm just wondering if since I'm getting 12 volts that's why everything is going caotic and acting like this.

 

[Clunk]

Here's some info about a faulty alternator "leaking" AC voltage into the system, indicating a problem....might be something else to check if your multimeter will read AC millivolts.

Mopar1973Man's Dodge Cummins Articles - Torque Converter Lock/Unlock Issues

 

[jmatt]

It has been fine the past few days but I'm just wondering if the smarty didn't download the software correctly and that was causing it. Haven't put it back on since but I might do it and see if it changes. Anyone else have an opinion of what it could be