Engine/Transmission (1994 - 1998) alternator doesn't always charge

[Hootguy]

Well,,i have been having charging issues layely,,,sometimes when i start my truck the alternator wont charge,,,i know the PCM wont let it charge while the grid heaters are on,,this is without the heaters on,,,

The grid heaters had a habit of sticking and killing the batteries so i put the trigger wires on a momentary switch so this way even if the relays stick it wont leave me stranded with dead batteries,,,also,,when it fails to charge,,i hit the alternator bracket a few times with a hammer and that usually starts it charging. .

Anyone have any ideas,,or if there is a way of putting in an alternator that does not rely on the PCM for control. .

Thanks

 

[wcjp]

Sounds like the alternator is done. Have you had it tested?

 

[robbiesworld]

Well it looks like you found the problem with the hammer method. I used that same method to get an employee to start working one time. Like your alternator, eventually I had to replace him.



It also ****** me off that the PCM had to know the truck was running to tell the alternator to start working.



Good question.

 

[Moe]

Check your crank sensor that looks at the balancer. If it cant "see" the crank turning then it wont charge. The engine will still run. MOE

 

[WilsonF]

You could try this, post #19, but it does sound like the alt.


Truck no charge-y! - Page 2 - Dodge Diesel - Diesel Truck Resource Forums

Floyd

 

[Hootguy]

Wow,,thanks for all the replies,,good information,,i'll check the crank sensor as suggested. .

Sure would be nice to have a stand alone alternator and voltage regulator.

 

[fest3er]

You know, for less than $50, you can replace your intake heater relays with better ones. Here is my solution. The relays still sound like new after 7 years; in contrast, the OEM relay units never lasted more than two years.

 

[robbiesworld]

Wow,,thanks for all the replies,,good information,,i'll check the crank sensor as suggested. .

Sure would be nice to have a stand alone alternator and voltage regulator.

if your ESS engine speed sensor on the crank is bad you will have other problems like no cruise control, no overdrive, no lockup, no tachometer and of course no charging

 

[Hootguy]

everything else works fine,,intermitent electrical problems have got to be the worse,,some one suggested just getting the alternator rebuilt to begin with,,since i have about 400,000 km that sounds like a good idea maybe,,but my 93 cummins dodge went 1,000,000. km's on the stock alternator. .

 

[DGendron]

Had that problem one cold cold winter,volt meter was showing not charging in dash like when heaters are on,then as your driving gets back to normal RPM up,replaced alt,perfect since.

 

[Missouri Mule]

You can wire an old fashion remote voltage regulator to the alternator but this sounds like a bad connection/wire/alternator.



The PCM has a EVR (electronic voltage regulator) inside of it. The EVR gets data from the BAttery Temp sensor and the ASD relay, naturally the battery temp sensor tells the EVR the temp of the battery the ASD sends the line voltage to the EVR. Then the EVR tells the Alternator what voltage to put out.



The Engine Speed Senor (crank speed sensor) activates the ASD relay. So if your tach, overdrive, A/C, charging works your ESS is working.