No charge situation

[DThibault]

My 93 W350 stopped charging so I did what I know and now I need what you know. The alternator is fine, putting out about 30 amps on the bench, the crank position sensor is new and I think adjusted properly. The multimeter shows no power at either of the field connections when the key is on and engine not running, after starting I get about 4. 5 amps on each field terminal. I don't know how to check the engine computer (PCM)? Any ideas? Thanks.

 

[DThibault]

L forgot to mention that the "Check engine" light is also on.

 

[Bob Beauchaine]

Have you checked for codes? If so what did you come up with?



Bob

 

[DThibault]

No, I didn't even know there was a place to read codes on that truck. Is it under the dash?

 

[Bob Beauchaine]

You read codes using the ignition and the check engine light. Turn the ignition key from the off position to the run position twice - do not start the engine the third time you leave the key in the run position then watch the check engine light. The CE light will flash 4 times pause the flash 1 or 2 times. The first series of flashes is the first digit and the second is the second digit. In the above case the code is 41. When all codes are run the CE light will flash 5 times pause and flash 5 more times - this means that the system is done and there are no more codes. If I remember there are only 3 codes relating to the alternator - can't remember what they all mean but I have a tech manual so I can give you an answer if you post the number.



Bob

 

[DThibault]

I'll try it. I'm going away for a couple of days but when I get back I'll run them. Thanks

 

[Bob Beauchaine]

Code 41 = Generator Field Control - Charging System. The PCM controls this.



Code 46 = Charging System Voltage.



Code 47 = Charging System Voltage. - Engine RPM above 1500.



There are how to's about the use of an exterior stand alone regulator to get your alt back in working order.



Bob

 

[RWherley]

On the 93's you can use a code reader that reads OBD1 with a Chrysler plug on it. the plug on the truck is under the hood on the left side of the truck in the back corner it has an odd shap to it and i think six pins in it.

 

[DThibault]

Bob, I got 41, 42 and 47. Do you know what the 42 means? Thanks for your help. I never knew there was any means to check codes in these trucks. I have a 91. 5 and that has an external regulator which is what I'll probably end up with.

 

[Bob Beauchaine]

My Tech Manual says:

"If the battery sence voltage is more than 1 volt above the desired control voltage for more than 20 seconds".

Since my alternator runs consistantly runs at about 14. 10 volts I would suspect that it is above that voltage. I would get a volt meter and check voltage at both the battery and the alternator and see what you get. Let us know what you get. It sounds as if you might have to replace the voltage regulator. They cost less than $20. 00 from what I understand.

Bob

 

[DThibault]

I picked up a regulator and the rubber plug that fits it. Somewhere here I saw an article how to wire it. Can't find it this morning. Can anyone steer me in the right direction? Thanks