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Hopefully someone more experienced in the electrical side of things can chime in on this one.
My mom just bought a 96 ram 1500 with the 5.2, it wasn’t running when she bought it, but it was a clean truck, and for what the truck has and what she paid for it, it was a good deal to jump on.
Anyhow, the guy she bought it from said he thought the crank position sensor was the issue, ok $70 bucks, worth a shot. well I turned the key to the ON position and listened for the fuel pump to prime and it didn’t, checked for pressure at the rail and there was none. so I checked the 20A fuse under the hood for the fuel pump and sure enough it was blown. so I swapped it with a slightly higher amperage fuse just to test it and the fuel pump primed and the truck fired up, then shut down. now when you turn the key to the ON position, the fuel pump just keeps running, and the relays in the underhood block click like crazy until you turn the key off. and it won’t start back up. anyone have any ideas? I’m leaning towards a short in the circuit, or a bad ECM possibly, but before I start really getting into this thing I wanted to get some suggestions. thanks in advance.
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ok, so whatever the issue is has to be after the ASD relay. so I’m gonna have to find any diagrams that pertain to that part of the circuit and go thru everything with a fine tooth comb.
I copied the links and instructions, you can take em down. thanks man.There is a couple other things I’d want to try.
First is to take the fuel pump fuse out and then turn the key on. Wait five or six seconds and then plug a fuse back into the fuel pump circuit. The ASD relay is turned on for self testing and IIRC gets shut back off until the PCM gets a crank signal. That might help tell you whether or not the short is actually tied to the ASD relay.
The other thing I forgot about the other day is that the Mitchell diagram shows that the fuel pump fuse also sends power to the transmission relay. Pull that transmission relay and see if you stop popping fuses that way too.
Sorry I forgot about that part, but there’s a lot of details to cover.
It’s late, I’m going to call it a night.
Good luck and keep us posted.
i’ll give that a shot next chance I get to mess with the truck. I’ve been at it for days, I might take the day off tomorrow. may be a day or two til I have the time to put into it. but I’ll update as I go. hopefully I can conclude soon with a video of the truck running. but we’ll see.
[quote=”no_common_sense” post=161191]Fuse 9 is a wash. It supplies power to the ASD relay. Disconnecting the ECU also disables the ASD relay so that’s a wash. Any fuse blocks inside the cabin are probably irrelevant so don’t bother trying to remove it. I was only interested in the under hood block. I don’t know what to say for that grey plug. They do the same thing with the ECU. It likewise gets a black, grey, and white connector to it.
This is where I miss private messaging. I’ve been primarily been using a login to identifix and that’s a login that’s been assigned to me at work. I can’t share that with you. I used to use this link a lot for OE diagram access. It might help you out on future endeavors.[/quote]
Best Link EVAR!!! Thank you!
being the glutton for punishment I am, and slightly OCD in that once I start something I have a hard time not finishing it.. lol
got home from work at 8pm and figured I had a few minutes so I tried the 2 things you suggested no_common_sense, the waiting a few then putting the fuse in resulted in another sacrificial fuse lol
however, pulled the trans relay, put a new fuse in and it fired right up.. obviously at this point the problem lies either in the harness going to the trans, or an electrical component related to the trans. now I have to try to find diagrams for that part of the circuit and start a process of elimination. the previous owner had said about going down the highway and it shut down and wouldn’t fire back up. any ideas on places to check based off the diagrams you’ve seen?
and seriously, thank you guys, I wouldn’t have gotten this far with it without your input.
Reread those Mitchell diagrams from the library. Page three sends you right to the transmission solenoid pack from the relay. Disconnect the connector for the solenoids down at the transmission, plug the transmission relay back in and look for a fuse to blow. Personally, I hope you find a short in the harness first. I don’t know how much digging you’d have to do inside the transmission if it turns out one of the solenoids is shorted out. The valve body may have to come out depending on which solenoid potentially went bad.
At an rate, I’m glad to hear you’re honing in on the source.
right on, I’ll give that a shot. that’s a little more than just pulling fuses so that’ll probably have to wait til I have a day off, working morning to night doesn’t lend itself to working on vehicles without a garage very well.
I went thru the diagrams on the trans circuit, I think part of my problem with electrical is diagrams like that confuse me when I try to put them together in my head, schematics as far as guitar amplifiers and effects I can do, but stuff like this just stumps me for some reason. I’ll go thru a process of elimination next chance I get, and hopefully I can get that sorted and move on to the maintenance I’m good at and get this thing road worthy for my mom.
Have no fear, you’ll be an expert with these diagrams before this adventure is over with…whether you like it or not.
I know that Dodge/Chrysler/Jeeps have issues with the governor pressure solenoid and transducer inside the transmission. I’m helping a buddy replace both in his jeep this weekend. The Rams have these sensors inside the tranny as well. I’m not sure if either of these would cause a no start situation and blow fuses, but I do not believe it requires completely pulling the valve body.
Thanks for the updates on progress!
no_common_sense, I’m thinking you maybe right on that one lol
andrewwebb58, Chryslers have always had problems with electrical and transmissions. and no problem, there will be more updates, just might be a couple days.
FOUND THE CULPRIT!!
the wiring harness inside the valvebody that goes to the governor and shift solenoids had gotten hot and slightly melted together, 2 wires were touching.I’m going to fix the harness, put some trans fluid in with a new filter, and hopefully the trans actually works… fingers crossed on that one considering what I found inside the pan when I pulled it.
not 100% sure when I’ll get a chance to put it all back together, going to try tomorrow if the weather and schedules line up.
You should do something about those solenoids while you’re in there. At least one of them could be the reason why the wires got hot and melted together. Ohm test the solenoids and I’ll try to find a spec for them. We’ve already got a warning that these solenoids are pattern failure parts. I’d rather see you heed that warning.
I intended to check impedence on them while I was in there. i think the trans overheated and that melted them.. i’m gonna check the cooler and lines as well while i’m fiddling with it, but i’m willing to gamble the 40 bucks in fluid and filter to see if the trans is even worth messing with.
The people that write this service information just slay me. I have found all kinds of words that suggest they’re finding more than one way to describe the same damn parts. I find some information for the overdrive solenoid which is probably the 3-4 shift solenoid in other lingo. I find information for a variable force solenoid which is also likely to just be the governor pressure solenoid. So here goes…
overdrive solenoid AND/OR 3-4 shift solenoid ohm spec = 25-40 Ω
governor solenoid AND/OR variable force solenoid ohm spec = 3-5Ω
torque converter clutch solenoid ohm spec = 25-40Ω
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