'93 CTD Won't Start -- entertaining symptoms

[RBurleson]

My 93 W250 would not fire last Friday. I had no time to deal with it, so I tossed a loaded checkbook past my wife to distract her, then grabbed her keys and 'borrowed' her car. I got home that night, and flipped on the parking lights to troubleshoot... I got no response from the interior or exterior lights, regardless of the state of the ignition. Since it was raining, I elected to postpone further analysis.



Later that evening, a neighbor rang my doorbell and asked if I knew I had left my lights on. Baffled, I walked out, and found that the previous situation had changed: with no input from anyone, the truck had seemingly 'healed' its connections and the lights that I had left switched on (they weren't lit earlier, so I forgot them) had actually lit up. Skeptical, I hopped in, and keyed the ignition. Startup sequence went normally, with full lamp check in the Message Center and a 15-second cycle of the Wait-to-Start (WtS) light. When the WtS light blinked out, I keyed over the starter and was greeted by darkness. Every light ceased to function (headlights, brakelights, dome light, dash lights). It was still raining, so I elected to punt once again, this time remembering to leave all switches in the 'off' position.



Saturday brought a sunny day, so I looked into this further. By then, the lights (dash, dome, and head) had resumed their normal functioning, accompanied by the sneering piezo of the door buzzer (I miss the gentle chime of my uncle's Caddy). The startup sequence was back to normal, as well, with a full lamp check in the Message Center and a 15-second cycle of the Wait-to-Start (WtS) light. This time, after waiting for the WtS light to shut off, I keyed the starter over successfully, and my Dodge roared to life. Cool, I thought!



I walked into the shop to grab some tools to clean the battery terminals (never a bad idea), and let the Dodge idle. Two minutes later, as I returned, it just shut off. It didn't bog, or surge, it just *stopped*. The plot thickens. I checked the lights, and the heads, brakes, dome, and dash lights functioned fine, but the Message Center showed no signs of life, not even the lamp test after turning the ignition key. No start, either. Still more thickness in plot, apparently.



I proceeded to clean both terminals (which looked fine, FWIW), and that's where she sits. I can hardly wait to see what new symptoms await this evening... I'm beginning to wonder whether Lucas, that dark English prince, had a hand in developing Dodge's electronics.



My current sypmtoms are similar to this fella:

https://www.turbodieselregistry.com/forums/showthread.php?s=&threadid=2202&highlight=wont+start

I still get headlights/buzzer/dome light/dashlights but nothing in the 'message center' and no cranking. No self-test from the 'message center' and no wait-to-start light.



As entertained as I am by the continually changing symptoms, I'd like to resume driving my Dodge. I'd love to listen to suggestions about what might be wrong...



Randii

 

[RBurleson]

FWIW, I read the topics in the First Gen forum that returned off the search criteria "won't start" and also "wait to start message center" -- if I'm missing an obvious set of search criteria, lemme know.



Randii

 

[RBurleson]

My current plan of attack is to grab the multimeter and dive under the hood to check the following:

* check the primary fusible links

* resistance between the battery and ground

* current at the starter (non-switched terminal)

* current at the relay bus (fuel pump, starter, and AC clutch, IIRC)



From there I'll branch out to up under the dash, where I've been told the ignition switch and headlight/dimmer combination switch are common failures. I'll also check the power to the fuse panel under the steering wheel... . unfortunately, the previous owners of this truck made a real mess of that wiring, and I have yet to correct it all...



Suggestions? It would seem to me that the diesel control box by the battery would be a good place to look, as would the relay to the fuel cutoff solenoid. I can think of a bunch of reasons why a CTD wouldn't start in the first place (most of which are pretty easy to bypass-test), but only a few reasons why a CTD would **stop** running in the midst of a normal idle.



I'm guessing I have at least two overlapping problems here.



Randii

 

[BushWakr - RIP]

How about the connections on the starter and the chassis ground going from the negative terminal on the battery to the radiator support.

That one gets pooched pretty often. .



I suck at electrical things but I'm all you've got till someone with electrical know-how gets in here... .



Bob.

 

[Philip]

I still get headlights/buzzer/dome light/dash lights

These items are not run threw the ignition switch. They are hot threw the fuse box all the time.



So if the above items are working that takes the bad ground thoughts out of the problem. All the lights total will pull around 20 or so amps. If you have enough ground for that. Then the other dash related items should work.



I would head around the ignition switch area. I think you will find some frayed or broken wires or a bad switch.

 

[formula]

I'll second looking at the ignition switch and associated wiring. Also check the fusible link block that sits on top of the driver's side fender. There may be a bad or partially burned out connection there. About a year ago I had the ignition switch short out and burn up a couple of those fusible links. Made a heck of a noise and a nice cloud of terrible smelling smoke spewed from under the hood. Damage was minimal, replaced the switch and fusible links and all is fine



Sean

 

[RBurleson]

No time to make progress yet, but I appreciate the suggestions.



Add to the bafflement that the heater fan kicks on with the keys turned, so it doesn't make total sense that it would be the ignition switch. Still, I hope so -- that's an easier task than running the whole wiring harness... .



Randii

 

[cerberusiam]

Check the fusible links carefully, not only for power but also for connection at the firewall end. If somebody has made a mess of the wiring its a good bet a fusible link has burned and been replaced. They will corrode at the connection to real wire and cause all kinds of problems. Mine had the same problem on a link that had been replaced. Everything completely quit and after slamming the door a couple of times the lights came on and it started then quit again. The link had been replaced and was good but it was not making a good connection at the wire it was spliced to.

 

[RBurleson]

Shortly after I bough the truck, I moved all non-OEM systems off the battery to a secondary post to make troubleshooting easier. The supplementary systems are separate but still messy, and frankly, the Dodge harness is less than lucid from the factory.



In the few minutes I had this morning, I started inspecting the fuel solenoid (shutoff 'noid, not the KSB) and found a section of insulator worn away where the blue wire crosses a bracket, with signs of electrical contact on that bracket. This might explain why the truck just stopped in the midst of a normal idle. I'm a bit baffled by the two wires on it -- one is trigger (when energized, allows fuel to flow to the pump, when de-energized, is spring-driven to shut-off fuel flow). What's the black wire that shares the same terminal, then?



I need to backtrack that blue wire to see what might have been damaged upstream. I do hope to find something simple like a roasted fuse, we'll see. This feels like a more complex failure than that, since 1. ) it stopped running (no sputtering, just stop), 2. ) it won't start now, and 3. ) the message center won't light up.



I'll post more when I know more...



Randii

 

[RBurleson]

Interesting post from the archives:

https://www.turbodieselregistry.com/forums/showthread.php?s=&threadid=43151&highlight=solenoid+fuel

"A 93 does NOT need the PCM to run. The fuel solenoid is fed directly from the ignition switch. "

... plenty of good specific things to check there.



This may all circle back to the ignition switch. Time to bust open the steering column, I guess.



Randii

 

[cerberusiam]

The second wire off the shutoff solenoid runs back to the intake temp sensor and then to the cold start solenoid to provide cold idle enrich and injection advance. You should be able to run the engine with all accessories off and just the shutoff solenoid energized or taken apart and manually on. In other words once the engine is running the key will not shutoff the engine if the shutoff is in manual mode. What 'no start' condition do you now have? No fire from the engine with cranking or no cranking at all?



You might have fried the PCM with a short on some of these wires. That would account for no message center lights.



When the shutoff solenoid wire rubbed bare on mine it blew another on of the fusible links. Now have 2 replaced with fused wires. Need an external fuse box soon as they are a constant source of annoyance.

 

[RBurleson]

What 'no start' condition do you now have? No fire from the engine with cranking or no cranking at all?

The current condition is no cranking at all... I need the truck badly tomorrow for a short-haul, so I am tempted to jump the fuel solenoid and short the starter to get a one-day fix...



You might have fried the PCM with a short on some of these wires.

NOT what I wanted to hear, but a real possibility. I would expect the circuit protection to be between the battery and the PCM. We'll see.



Thanks,



Randii

 

[Bob Beauchaine]

If the fuel shut off solenoid is bad you will probably have to remove it and "gut" it then reinstall it. At this point the truck should run but you will have to manually shut it down. The fuel shut off solenoid will not cause a no crank condition. Your truck should turn over but not start or if running not shut off with the ignition key.



I've got a '93 tech manual so if I can be of any help PM me and we can trade phone numbers. If we set up a time I can have my manual ready and maybe we can put some ideas together and get you back on the road.



Bob

 

[cerberusiam]

Like Bob said the fuel shutoff will not cause a no crank condition. Somewhere power is not getting to the starter relay or the starter contacts are not working correctly, could be either one. You could try jumping the start to see if it will turn over and start.



The protection for the PCM is the fusible links. The problem arises when the voltage condition happens on a bad connection. There are 2 things that will toast a PCM almost immediately and that is a low voltage condition and a bad ground. Protection for high voltage was designed in but the plannned obsolescence did not account for age of the vehicle and parts. Big pain but an unfortunate truth.

 

[MMiller]

Just a couple more ideas. Look at the wires to the ignition switch where the column tilts. My cruise control wires failed in this area after years of the column going up and down, maybe a ground or something for your ignition.



I ain't there but I would be leaning twards a bad ground. I have fought a lot of weird problems that came down to a bad ground, not just on the dodge, but Cats, trailers etc. Sounds kinda hokee with intermintant problems.



Fusable links are a good thing to check too.



Let us know how it goes!



Michael

 

[Greenleaf]

Any luck yet?

Two things to take a close look at; Battery cable connection at the starter solenoid and the pig tail connected to the pos battery post terminal. It's the one about four inches long. Heavy wire with a long cylindrical connection at the end[about four inches from the bat post terminal] Wiggle this wire with the ignition in on position. Have a body in the cab to tell you when it's making a connection. I have a radar detector to beep on/off for me. Clean it well and bend the female half of this connection a bit to allow for a tighter fit.



Don't just look at the connection down on starter solenoid... . CLEAN IT!! You did clean the batttery posts, right?



Scott

 

[RBurleson]

Bob, I may take you up on that tech manual assistance, but I gotta get through the week first. This afternoon is a scouting trip with the BLM's botanist to plan a conservation weekend (the road to get there, not his stinkin' weeds!) and tomorrow I present a the proposal for rejuvenating the 4x4 section of the local state vehicular recreation area ( www.pc4x4pc.com if you're bored), all worked around my pesky day-job. I think I'll find time to troubleshoot the Dodge on Friday.



The good news is that I hotwired the fuel solenoid and starter, and got it running today. The chief functional shortfall right now is absence of alternator charging and turn signals, but I'm short-tripping through low-traffic areas until I get this fixed.



FWIW, I have removed, cleaned, and replaced all cables that hit the battery, starter, and core support (the signal wire to the starter solenoid is a BUGGER to reach), but I still believe that there's several failures at work here: stopping, starting, and intermittent lights. As noted, I had a short to a bracket on the blue wire that triggers the fuel solenoid. The solenoid itself is fine, as witnessed by me driving the Dodge today. I believe that this short failed something further upstream (I'm hoping not the PCM but will need to backprobe the source wires on the battery side of it to be sure), and the resultant failure affected the normal startup process (tough to back out the chicken or the egg, here). The intermittent light issue is almost surely a separate fault, probably related to the flakey headlight combo switch I have been meaning to replace, or perhaps caused by the battery post corrosion that I have already cleaned (I'm reaching a bit on this one, that switch is a bit of a PITA to replace, especially since I need to replace the wiring harness connector).



Thanks for the support and suggestions... its on me to make time to run this down, now!



Randii (feeling parenthetical today, apparently)

 

[BushWakr - RIP]

"... Randii. . (feeling parenthetical today, apparently)... "



Stand back guys... . this fella is DEEP ... .



Ok the word for today is... ... . parenthetical ... . got it...



I think that means your parents are pathetic...



have I mentioned that I really suck at electrical things..... sorry I can't be of more help here randii... .



pastor b0b

 

[Greenleaf]

Yeah,my father is looking into buying another pickup, one of them Toyota Tecoma-hul-nothings that screams "smoke me!!" Now if that's not pathetic I don't know what is.