'94 lebaron conv / asd issue

QuestionEdit

QUESTION: Hi Roland,

Re: '94 Chrysler Lebaron, Conv., 3.0L

I have looked over a few of your threads and have attempted some of your diagnostic advice.

This vehicle had recent coolant leak due to eroded metal transfer coolant pipe (under plenum). Engine cut out underway recently, registering codes 35 & 42 (via key on/off).

Jumped the relay second in on my fuse/relay panel (marked inj. ign. coil), still no spark from coil. Since four of the relays in this box are same type, I interchanged one from the air cond clutch position, to the other ports (to no solution).

Per code 35, Fuses look good, and I have cleaned of corrosion and reseated. Not sure where to head next on this code, which please correct, but I read that this probable opened the ASD, and could be the root problem

ANSWER: Hi Jerry, The power to operate the coil of the ASD relay comes from the 20 amp mini-fuse between contacts 42 and 43 in the in board front corner of the power distribution center, so verify that fuse is working, and that power is arriving at the inboard pin of the ASD socket. If the relay is good, when the relay is closed by means of the pcm grounding the outboard pin of the socket then 12v on the rear pin of the socket is connected to the front pin of the socket which in turn provides power to the spark coil and the field coil of the alternator. So verify that you have 12v on the rear pin which comes from the fuse adjacent to 42/43 and which is numbered 44/45. If you jumped the relay socket from back to front then you should have 12v on the spark coil dark green/orange wire. If you verify all that, and still no spark then I would check the codes again to verify that the pcm is seeing the spark generating pulsing that comes from the distributor and which if absent would be a code 11 or 54. The radiator fan relay does share 41/42 fuse output to power its coil, so that would be the probable cause of that code which is common to it and to the ASD actuation coil. Another thing to check would be that the ignition switch's pin 2 (dark blue wire) shows 12v in the 'run' position as that is what powers 41/42 fuse as well as fuses 14,15,16 under the dash. You may simply have a bad ignition switch. Somewhere in these circuits I described you will find the problem. Roland PS: Please rate my answer (see below). Thanks

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QUESTION: Hot at 42/43. Hot at 44/45. Jumped the ASD socket and got juice at the green/orange coil wire. (should I have juice on the green/orange with the relay in place?).

DC'd the battery, so a ? on your code 11 or 54 proposed. Back to the expected codes 12 and 55.

Under dash fuse 14 and 16 hot. 15 is COLD(speed control circ.)???

Replace Coil in the past 12 months. Could this be a Coil failure???

Thanks, Jerry

ANSWER: Hi Jerry, The green/orange wire should be 12V for about 1 second when you first turn the key to 'run' position, and likewise the fuel pump should be heard to run for that same 1 second. The 12V would be expected to appear again when you begin to crank over the starter motor. That is the normal function of the ASD relay coil activation. If it doesn't do that, then either the ASD is bad, or the pulsing from the rotational sensors is not appearing at the pcm so it refuses to activate the ASD coil. If the ASD closes as described above and closes when cranking, then the pcm should be driving the primary of the spark coil to give you spark, but that driving can't be 'seen' with unless you have an oscilloscope. But if the pulsing is not getting to the pcm then as I said a code 11 or 54 would be set. Is the rotor moving when you are cranking it? as it may be the timing belt has broken.

1. 15 should also be 'hot' along with 14 and 16 because they are on the same bus.

Roland PS Thanks for the kind remarks and nomination. By the way you are entitled to rate this answer as well, and even do another nomination if you so choose.

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QUESTION: Roland,

I think you nailed it!

Get a one second 12V burst at the green/orange coil wire and a power up of the fuel pump with relay in place. No juice to the green/orange during engine crank.

Pulled the distributor cap and cranked...no turn on the rotor....WhaaaLa.

PS-Tried to make contact with the no heat number 15 for 3X. After the timing belt remove and replace....we'll see if its an issue.

PSS-I am sure the belt issue has caused me another curve to climb. You have any procedure steps to line up crank, cams, rotor with the new belt install? All I have is a Haynes manual. I replaced the H2O pump and remember marking carefully because the manual was sketchy. I am sure the marks are gone now.

AnswerEdit

Hi Jerry, I compared the Chrysler manual to the Haynes and it appears the two are in agreement and nothing is overlooked between the two. I don't have the 3.0L manual digitally, only hard copy which I could xerox the belt install pages from and postal mail to you if you would like. The main pitfall is to not get the distributor rotor positioned properly when you put it back in (if you have removed it). As the manual shows there is some re-ordering of the wire external/internal positions built-in to the distributor cap. When the engine is at TDC for cyl 1 the rotor would be lined up axially along engine with the tip of the rotor pointed toward the transmission.The alignment marks for the crankshaft and the two camshaft sprockets should be quite noticeable. Best of luck on the task ahead. And once again, I appreciate very much the nominations. Roland

PS: Let me know your postal mailing address should you want the pages. Ask a new question, check the box for making it PRIVATE, and tell me that.