I probed the connector the way wannadiesel described in the link diesel402004 sent ( thank you by the way) and all checked out good. I also back probed it the way jmartin told me to. Everything checked out good except pin 57. ? I do not have a diagram to what this wire does. Can yall help me

 

I think Geno's garage has reprints. Not cheap, but worth every penny when you need to trouble shoot things.

Or you can try E-bay, or craigslist for a used copy...but many sellers want a pretty penny for a beat up example though.

I lucked out one night while cruising craigslist...old guy had an original one for sale for $25...and he brought it most of the way to my house.

 

Thanks thrashingcows. Im a craigslist addict myself. I'll have to track one down and figure out what this wire does. I know jmartin said its for ASD relay I believe but I swapped the relays and it does the same thing. Im going to track that wire manually and see if its broke or loose. Thank yall again for all yalls knowledge.

 

Ignition switch comes in on pin 9, then the PCM grounds pin 51 which energizes the ASD relay. The ASD relay then supplies 12V to the alternator and also pin 57 of the PCM. If that voltage is low, the PCM thinks the battery is low. If it's too low, I suspect OD and AC might not work.

The 12V comes through a fusible link to the ASD relay, then to the PCM pin 57.

You can get a FSM on CD from Geno's for about 30 bucks.

 

Right forgot about those....and they are a "searchable" database too are they not?

 

So does this mean there is a wiring issue at the fuseable links or that the ASD relay is malfunctioning. Its 5 speed so no od but could be why cruise isnt working if ASD relay isnt functioning properly. AC works just like it should.

 

If I understand you correctly Mr. Martin I should first check to make sure PCM is grounding pin 51 energizing the relay. If thats good then it has to be a wiring issue from the relay back to the PCM correct?

 

The printed version is available new from genos for 110 bucks, but I have both for my 97 and find the CD version gets used 20X more than my printed one, not to mention it is MUCH cheaper.

I keep a copy of the file on my phone in memory and have a flash drive of it in the glove box, that way if I am broke down on the road, all I have to do is find a computer. When I finally join the modern world with a smart phone, I will be all set....... no worries about finding a computer.

Here is the 93 CD version.

1993 Dodge Ram Factory Service Manual - CD Version-Geno's Garage

 

If AC works, ASD is good.

Just so you are clear about it, these things don't use the 12V to regulate, they make the ground in the PCM. When you have a no-charge condition, you ground out the green wire to see if it goes to full charge.

That is the primary reason I don't think you have a PCM issue, if it dead shorted inside to ground, it would be overcharging all the time.

That being said, if the green wire has become chaffed or cracked, and is grounding anywhere between the alternator and the PCM, she will go full charge on you without any input from the PCM.

It is very common for a chaffed wire to start out intermittent and get worse.....

 

Yes. I have access to a professional printer, so I printed a copy double sided and punched. Takes several large binders. Because I use them a lot helping others, I printed an extra copy of the 8W diagram pages and keep them handy. In practice, when I go after something, I search it out in the manual, print out the pages needed, take them out in the shop, get them tattered and greasy in short order, then discard them.

Without knowing exactly what you found when you probed, I can't offer an informed opinion.

Good thinking.

I agree, the most likely fault here is a chaffed wire between the PCM and the alternator. It could also be an internal fault in the alternator. If the ASD relay had a high contact resistance, and caused a low voltage to the PCM, it could cause the PCM to over-regulate just like a bad PCM ground would.

It's beginning to look like charging and cruise are separate issues in this case.

 

Once you get the FSM you can work through all the diagnostic test for the cruise...and there are a lot in there! Test everything from the switches, right down to the signals coming from the PCM. Something will show up to explain your cruise issue.

My system checks out on everything, but it still wants to accelerate...be it slowly now...once cruise is set.

 

Just got home and started looking for pin 51 to check for ground. Pin 51 is an empty slot.

 

Pin 51 should have a 20g Dark Blue/Yellow wire going to the ASD relay coil terminal opposite the Dark Blue wire from the ignition feed.

 

I literally just took my entire engine side wiring harness off my truck. Sat on the shop floor and cut every inch of electrical tape and wire loom off and chased every single wire from alternator to relays and pcm. All wires are very good shape. No splits cuts chaffing or anything. Notices truck is harder to start than usual. Usually just a bump of the key and hes off n running. Takes a few turns before he pops off now. Voltage on dash-o-meter is 8-10 with key on. When is starts it jumps to 14-16. Holds steady for a few then intermittently peggs out n levels back out. Still getting code 41. Im lost gentlemen. I ordered the FSM but another week without my rig is gonna kill me. Its been 3 weeks now. Any more thoughts

 

I must be counting the pins wrong. Im doing it the way wannadiesel described in the link I recieved from diesel402004. With the connector disconnected looking at it from the driver side fender with the wires from the connector going toward to firewall. Top left is pin 1 and counting from left to right.