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Discussion Starter · #3 ·
electrica but im going to try the key test for codes. what i was looking for was the ecm someone told me it could be in the heating duct. but that sounded a little strange
 

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AirFuelEddie
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I would say that is incorrect. try looking behind the battery cavity near the headlight bucket. It should be right behind there with a plastic tube that allows air into the SBEC,(Single Board Engine Controller or it's now refferred to as the PCM,(PowerTrainControl Module), the tubing allowed cool air into the 'PCM's" motherboards and relays, this cools the unit, Chrysler later placed all the relays on the outside of the PCM. To test the SBEC you need to find the OBD-I connector near the hood hinge on the drivers side, it's a 6 pin connector, plugs into any generic scan tool provided you have the 6 pin connection adaptor for Chrysler, most OBD-I scan tools have assorted adaptors to hook into the 6 pin connector. But you can retrieve most of the codes from the key On/Engine off test. A piece of paper and pencil is handy, it will start with code 12 and end in 55,( one flash then pause, then 2 flashes)(5 flashes pause then 5 more flashes), this is normal, try to get the codes between these 2!! Good Luck
 

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Discussion Starter · #5 ·
1990 dodge fault codes

thanks for your help here is what i found. i did find the pcm.i ran the key on code search and found 12 42 51 55 taking 12 and 55 out. i have learned 42 is the code for auto shutdown z1 voltage missing and 51 internal logic module fault. what next new pcm and a auto shutdown?
 

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AirFuelEddie
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If the vehicle fails to start then,Take the ASD relay in to Auto-Zone or Napa, O'reillys ect and have em test it for you, it's usually free, and if it tests bad just pick a new one up there.
 

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AirFuelEddie
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dont worry about the 51 for now ? (internal logic module fault ) thanks again
Before I answer that I need to know a few things. Does the vehicle have a No -Start condition? If so, what did it do before this? Did you do any welding, or full field the alternator recently? Does the electrical system work?
 

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Discussion Starter · #9 ·
i couldnt get the asd tested tonight. the answer to your? is no ,nothing different than ever. i plow with it and it never fails me. litterally the starter never makes even 1 revelution before it starts. if any surge happened i didnt see it.yes there is a no start ,i ran the truck for 4 hrs the morrning it died i went into the shop for 10 min came back and no start.
 

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AirFuelEddie
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Does it crank over? Check for spark and fuel,(you'll be able to smell it after a cold start attempt),(Pull a plug wire and place to ground or use an old spark plug). if yes to both these the fuel pump is energizing, and the PCM is working.(A couple of simple tests, that will eliminate a lot of potential guessing and parts removal)
 

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Discussion Starter · #12 ·
it cranks great and no spark there is fuel when i did the jumper test.i read you disconnect the dist and jump the two out of three wires on the harness end. the idea behind that is it sends a fauls signal that it is running it should have fired the coil and injectors(no fire at coil). now it did fire the injectors and fuel cam out but i dont think the pump was running so it could just be the fuel left in the line . norm when i turn the key on i can here the fuel pump cycle once. but that isnt happening now. to be sure i have the correct auto shutdown relay that i think it is one of two bolted to the drivers side inner fender. ihope it is because that is what im going to try to have tested thismorn thanks
 

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AirFuelEddie
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If it allowed the fuel pump to operate and produced NO spark the PCM should still be fine. If the PCM was 'dead' you would get NO fuel NO spark. Now that I know all the facts you can perform this simple test to determine if the ignition coil is ok. Take a DVOM and place the black lead on a suitable ground and the red lead probe on the coil + terminal and crank the engine for 5 seconds while monitoring the voltage on the meter. It should show battery voltage or close to it (approx. 12.4-12.6 volts) but not for the entire 5 seconds. It should go to 12.6 approx and drop to about 9 volts after a 2-3 seconds. If it stays at 12.6 volts during the cranking further testing will have to be conducted but the SBEC"s usually are pretty hearty components. The ASD relay or distributor pick refernec signal,(Hall Effect sensor), are usually the first to fail before the SBEC, unless careless welding, or full fielding the alternator can destroy it,(spiked voltages can reach a point where the computers circuits cant handle it and it basically melts).
 

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I have a Hood Ornament that looks exactly like a 1947 Dodge Truck Hood Ornament except that it is made of LEAD , NOT chrome plated pot metal , and originally was painted Olive Drab ( Military ) with minor red paint detailing . The word LEAD is clearly cast into the bottom side of the ornament . #921737 appears on the bottom side . Production during 1942 - 43 was supposedly limited to military use , and painted Olive Drab ( Black Out Colors ) I have never heard of a Lead Hood Ornament before and was looking for additional information .
 

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Discussion Starter · #15 ·
i forgot 1 thing i put a brand new coil on it and a hall effect on. unless thoughs are bad out of the box im not heading that way yet. 1230 my new asd will be in at napa. after i install i will run the coil test.the one thing that is a little strange no auto parts store here in cleveland tests relays so i bought a new asd. Ipulled the pcmor (sbec )but am having a little trouble finding someone that can test it.when the asd gets ill plug it back in and try it.if i can get the sbec tested ill let you know. thanks again you have been a great help.
 

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AirFuelEddie
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one more thing after my review the injector fired but im not sure the fuel pump did at all
It would have to. The PCM 'looks' for the Hall Effect signal when the engine is cranking. If it doesnt recieve this signal in 2 seconds, it shuts the current flow off to the fuel pump, therefore no fuel delivery to the throttle body injectors. During normal operation on a cold start, the injectors should spray 2 times before the engine even cranks over. It receives the temperature input form the Cooolant Temp sensor. This one sensor alone determines the pulse width of fuel delivery to the engine especially during cold starts.
 

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Discussion Starter · #18 ·
im doing this while working sorry for the delay. I installed the new asd no luck. the ?i have is i understand the fuel pump and the injector 2 fire on cold start. i always here the pump cycle when i turn the key on ,i dont hear that now and still dont have fire. This is why im not sure when i did the fauls fire test from the dist harness that the fuel pump was running . the injectors did but the coil didnt . that is why i thought it could just be fuel left in the line. and it didnt spray hard like you think it might.im doing another test on the hall effect and the coill in the morrning thanks for sticking with it . any more ideas im trying to find a sbec used to test with but the 1990 has one only for that year i will find one i hope
 

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Discussion Starter · #19 ·
ok here is what i found new asd. i did the coil test while cranking but i never had batt voltage 11.50 was the most i got and it never drooped to 9 volts. what is my next test. kep in mind new coil and hall effect. plus i got my hands on a different sbec nothing different
 

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AirFuelEddie
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ok here is what i found new asd. i did the coil test while cranking but i never had batt voltage 11.50 was the most i got and it never drooped to 9 volts. what is my next test. kep in mind new coil and hall effect. plus i got my hands on a different sbec nothing different
Check the distributor reference signal. Its a 3 wire connection at the distributor. It should have a 3 wire connection. One wire is 5 volts DC constant,(thats the signal wire from the PCM), the other is a Hall Effect Sensor wire that produces up to 5 volts DC but only produces this signal at engine runnning. The other wire is a ground wire. So with the ignition on take your DMM or DVOM and test the signal wire for 5 volts with the key in the ignition turned on, not the engine, just the ignition. So one wire is ground, no voltage, the other wire should show very little voltage, the signal wire 5 volts steady. The wire's are usually Orange, grey, black ,,,
 
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