Chrysler Repair: starting problem, flex plate, starter relay

Question
Hi Roland, I have a 1993 voyager with the 3liter v6.  
I've had it for a year now with no problems. Until last night. it would not start, just a click. I checked the battery post for a good connection, it was good. i don't think it was the battery 'cause the interior lights came on no problem, as well with the headlights. I tried shifting to neutral, turning the wheel a bit, no start. I got a boost from my brother and it seemed like a long time to recharge. but like i said, it seems like it was not a battery problem, maybe something to do with the solenoid or starter relay. If you could help me locate the problem that would be super! One more thing...befor that problem had occured, earlier last night it had problems starting...a slow whurring, then it would start.

Answer
Hi Alex,
Did your Brother jump start the car, or did he bring over a battery charger to 'boost' the battery, it wasn't clear to me which. If the battery was recharged and it then was able to start the car, then that would indicate that the battery wasn't putting out either the voltage or the current necessary to initiate the starter mootor. It sounds to me like a week battery in that respect. The whirring sound is the starter motor but without its bendix drive gear engaged in the tranny flex plate ring gear, so the engine doesn't turn over. That might happen if the voltage to the solenoid is insufficient to drive the bendix gear out far enough to engage the ring gear. As long as you get action at the motor, the relay is probably o.k. unless there might be a voltage drop across the switch contacts inside the relay which would result in a reduced volatage to the solenoid. I would sduggest that you evaluate the age of the battery and see if it is reaching its warranty life. Then if it is "young" I would check the flluid level in the cells and then put it on a charger and see how that goes. You can even get an hygrometer which measures the specific gravity of the electrrolyte to tell you about the degree of charge on each cell (cost less than $5).
I wouldn't base tha battery performance on whether the lights dimmed, or the headlights came on, because if the motor is not turning over it is not drawing down the battery. You might want to remove the clamp negative post of the battery
then you can safely check the condition of the positive post, and even for good measure go to the starter motor and check the big red wire from the battery to the solenoid to make sure that it is clean and tight, and similarly check the brown wire to solenoid from the starter relay similarly. Then return to the battery and reconnect the negative pole's clamp.
I am doing these color codes by memory as I'm not at home today, but I think I have them correctly.
To avoid unnecessary repair parts and costs, doing the battery checkout and the wire connection cleaning and tightening would be a prudent approach. If after that you still have the problem then the question becomes the relay, the solenoid, or the starter motor proper. Testing the output voltage of the relay is probably the first thing to do, and make sure that the voltage arrives with little loss on the brown wire at the solenoid. If it seems to be getting there at 12V or more, only then I would suspect the solenoid or starter motor.