Chrysler Repair: 96 van 3.3/no spark, powertrain control module, plymouth grand voyager

Question
Hellow.My friend owns a 96 Plymouth Grand Voyager with 3.3L distributorless ignition. One morning her car would no longer start. There is fuel pressur but no spark. I scanned it but only get codes 12 & 55. I tested the auto shutdown rely and the coils and they pass. When testing the coil drive circuits from the computer 2 of the terminals first started off then blinked on and off dimly.But the red/yellow wire started on brightly and would dim but not blink on and off like the first two. Does my friend need another powertrain control module? Thanks Roland for your time.   LD--on the line

Answer
Hi David,
I got you question via the feedback option. I take it that you have the Haynes manual for referencing your testing. I believe that as described there you would expect to see each of the three coil driver wires at the coil plug blink rapidly in synchrony with the cam and crank sensors (once for each revolution of the engine on a given drive wire) which is the sign that the drive is momentarily grounding the end of the primary coil so as to produce a spark on the two spark plug wires driven by that section of the coil. If you have shown that you are getting 12v on the fourth wire at the coil plug, and that all three driver wires are showing an equal blinking response, and the coil resistance tests are passed, then you should be getting spark on all 6 cylinders. I would be inclined to test for spark at each of three plug wires that are driven by the separate coil drivers and to verify that you got spark on two of the three but not on the third spark wire (like cylinder 3 or 6, driven by the red/yellow) which was driven by the red/yellow wire which showed no blinking response. If you do that, then it pretty conclusively shows that there is either something wrong with the harness between the red/yellow wire at the coil and pin 19 of the pcm, or that the pcm function for pin 19 driver has gone bad. You could verify that the wire in the harness was neither grounded, nor shorted to one of the other driver wires in the harness so as to eliminate the harness as the cause. Once you do that, it would be reasonable to get a replacement PCM. I don't know how much the dealer charges but if it seems beyond reason then looking for a replacement at a salvage yard is an alternative. I would try to stay with the same model year and a van, and of course it would have to be one for the 3.3L engine for sure no matter what the year or body style.  
Roland