96 Dodge RamVan ignition

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Sorry folks I'm back w/ the issues of this van. (96 B1500, V6)1 I thought it would be better to start a new thread than continue my stalling thread from a few weeks ago.
(FYI. http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=3119258#Post3119258)

I would like to attempt more diagnostics myself, before I have it towed to a shop. I enjoy learning about different vehicles and more importantly, keeping my family's budget in shape. I am not very excited about throwing parts at it, but given my meager diagnostic toolset, that might just be what I need to do.

Here's where I'm at... ignition problems. I am getting no voltage at the coil.

I've made an attempt to get up to speed on the Dodge way... but I'm not quite there yet.

Here's what I've done:
Tested & charged battery- 12.2 V
Replaced rotor, cap, wires, & plugs.
Cleaned & tightened battery terminals
Disconnected aftermarket electronics (brake controller & tow connections)
Swapped Auto Shutdown relay with another

Diagnostics:
When I jumper through the ASD relay, I get 11.0V at the coil, but no spark
No OBD codes.

I've read how a bad sensor (crank?) can pull down the voltage coming from the ASD circuit. But, I haven't figured out how I can test for that without a Dodge diag. tool. It also was suggested that many cam sensors go bad in these V6 magnums.

Thanks for any/all tips, thoughts, or even well wishes
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If within so many seconds (15?) the ECM doesnt get an input signal from the crank or cam sensors,it will de-power the ASD relay which kills the fuel injection (fuel pump) and ignition systems.If you had a bad cam/crank sensor and bypassed the ASD (jump the terminals) it probably still wouldnt start.
 
OBD-II scanners are relatively inexpensive, and will pay for themselves just about as fast as a socket set will. I'd get one, If I were you.

As NHguy said, the ASD relay will de-power within a few seconds of turning the key on if the controller doesn't detect a cam/crank signal indicating that the engine is rotating. That's its JOB- to shut off the fuel and ignition sources if the engine isn't turning... say after a bad wreck.

If you can recruit a helper, have them operate the ignition key while you look for voltage at the coil.

1) ignition off- no voltage.
2) helper turns ignition on- voltage should appear for 2-3 seconds then go away.
3) helper cranks engine- voltage should come back while cranking.

If 2 happens but 3 doesn't, its pretty definitely the crank sensor (or cam sensor, which IIRC is in the distributor on Magnum series engines).
 
Very helpful. Thank you.

I do have an OBD-II tool, a fairly nice Actron. I haven't seen any data or codes that can help me yet. I'm probably missing something about using the tool.

I performed the above test and there was no voltage at the coil at any time.

Where does that leave me? I'm guessing either:

bad wiring
bad ECM
bad relay

But, again, swapping relays made no difference. So, I'm tenatively crossing that off the list. (Regretfully, since its the cheapest part.)

Does the fact that I get voltage at the coil when the ASD is jumped lead me to suspect ECM?
 
Not suggesting it is 'the' problem but 12.2 volts is not indicative of a fully charged battery.

In general 12.6 would be close to fully charged and if I get anything under 12.4 I consider it needs charging. 11.9 volts is basically no charge.
 
These relays are activated by switched grounds from the PCM.

Any Dodge van with weird electrical issues needs to have grounds eliminated as a culprit before pursuing other leads. Both battery to engine and battery to firewall ground need to be removed, filed shiny and retightened. Looking at and declaring them fine is not adequate.

The "Key dance" can reveal any PCM codes. You should be getting a code 12 and 55 at a minimum.

Sometimes failed/Failing PCM's can be coaxed into starting the vehicle if warmed with a hair dryer.

This era van does weird things when the battery is low or heavily sulfated with a fraction of its remaining capacity.

The cranks sensor is responsible for many no starts.
 
Thank you. I'll be sure to eliminate a weak battery and bad grounds from my future testing.

I've heard about the key dance... and now I've read about it too. I think my Check Engine light is burned out
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So, more to come. I sure wish my OBD tool would give me some info though.

Again, thank you for keeping me focused on the important things.
 
Status update:

Battery & grounds made good

All signs point to a bad ECM, such as:
OBD-II will not establish connection
The check-engine light won't light ever, even w/ a new good bulb

I'm deciding about whether I should get the ECM replaced at a shop. I'd be worried about ruining the new one if there's a bad sensor on the van that caused the old one to fail (or something similar.)

But, I could get a new programmed ECM with cam, crank, and TPS sensors for about $300 total. I'd have to worry about O2 sensors, wiring & Fuel pump shorts still.

I'm getting better at the techniques of wiring/ electronic testing using my multimeter.

Someone who's done this work before, talk some sense into me. Should I order the parts or hand off the van to an expert.
 
A shop is likely to just buy a new PCM, double its price, slap it in and charge you for 6 hours of labor.

Cardone says the most likely failure to PCM,s is the transmission solenoids or their wiring.

My ECM(1989) failed because some wiring to the transmission chafed in the slipstream and was grounding out on the bell housing.
 
I like that info., a lot. I definitely can check the wiring myself. I've been checking out some of it already, of course, but it kind of gets overwhelming for me.

Its kind of a good thing that I have young kids who keep me away from the van for days at a time. I can gradually get more info, and let the possibilities rattle around in my head longer.

I'm off to Chiltons to read up on txn solenoid wiring! Thanks
 
You should also try and wiggle the wiresand connectors at the engine computer with the ignition on and somebody to see if the CEL Illuminates briefly. If it does, remove and check the connectors at the engine computer, Battery disconnected. The computer not only cooks located as it is above the engine in the highest part of the hood, rainwater that drips into the hood can get onto the wires and funnel water to the PCM connectors. Genius design. I've had issues off and on with these computer connectors causing no starts and stalling, but I know exactly what it is cause the engine cranks, but No CEL light, no start.

I've redirected any rainwater that gets into the hood away from the ECM, wiring and bulkhead connector.

If you plan on keeping this Van, look to get a factory service manual from e bay motors. Much more in depth than a Haynes or Chilton.
 
Holy moly folks! I put in a new/refurb ECM this weekend, and the van is running!

I did also replace the whole ignition system, cam & crank sensors, PCV, valve cover grommets, check engine light bulb, battery, & battery hold down asm.

Here's the thing, the two things, actually.

I have a starter issue. It sometimes clunks, but doesn't crank. I noticed that the starter is pretty messy with oil/ grime. I want to check all the connections tonight before anything else.

Also, the check engine light came on after driving it for about 10 minutes this morning. I am so curious what the code is, but it will have to wait until this evening. Since I've never seen the check engine light on this van before this weekend, I have mixed feelings about seeing it now.

Thank you Bitogers. Your expertise is appreciated.
 
You can check the codes by doing the 'key dance'

Ignition off on(not start) 3 times then leave it on.

Watch the CEL light. it will go out, then start flashing

3 flashes a pause then 5 flashes is a code 35.

Expect to see code 12( battery has been disconnected within last 100 key starts), and code 55(end of codes) They don;t always flash numerically such as i have seen a code 15 ( speed sensor) flash after a code 51( o2 sensor)

Most Dodge OBD1 or 2 codes are universal but I have found some discrepencies between my factory service manual and the generic lists you can find online.

If you're gonna keep this van for a while, a service manual from E bay motors is the best investment you can make
 
I am interested in a service manual.

I had a look, but I saw a few manuals that seemed to be electrical only. Is the service manual a single volume or a set of volumes? Is there a better deal to be found for an electronic copy?
 
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