73 Challenger No Crank

[ChallengerHK]

Saturday I swapped out my wiper motor, after which it wouldn't crank. I checked the schematics, and there's a wire running from the park-neutral safety switch to the wiper motor, or perhaps to the little electronic doohickey mounted on the wiper motor. Can anyone clue me in as to what that electronic doohickey does, and how I can get back to a start situation?

I am a newby, BTW, and I will post an introduction and pic soon.

[Bullitt-]

On my '73 I see no electronics on the wiper, but just to the side is the ballast resistor, a white ceramic block, that is part of the ignition system. Will your car not turn over, or just won't start. If it won't start the ballast resistor may have been bumped during the process & damaged. You can test with an ohmeter, with the wires disconnected each side should read aprox. 1-OHM. If the meter reads open or varies during testing the resistor is bad.  Replacement can be found at local parts stores, I paid about $5.00 a month ago at Advance Auto.

[ChallengerHK]

Thanks for the reply, bullitt. It's not the ballast; believe I've had enough problems with ballasts over the year. I keep a spare in the glove box  .  And it is a no-crank situation, with an adequately charged battery, etc.

This is a very small affair encased in either ceramic or some other plastic. It's got two terminals, and it's mounted directly to the wiper motor housing with a single screw. My suspicion is that it has something to do with the auto-park feature.

[Bullitt-]

After studying the manual you must have a 2-speed wiper which has an extra gizmo that the 3-speed like I have does not. This is not part of the starter/interlock. The wiring diagram shows 3 wires coming from the switch on the automatic transmission. 2 of them go to the bulkhead connector while the 3rd goes to the starter relay. Do you have a schematic of the under hood wiring? if not here is a link
http://mymopar.com/wiringdiagrams.htm

[ChallengerHK]

Bullitt,

Correct on the two speed wiper motor. Do you have any idea what that extra gizmo does? Since the wiper motor itself is operating, that's the only thing I can think of that may be having a ground problem.  I'm attaching a pic I took yesterday, in case anyone can ID this part and its function.

Re: the schematics, if I traced everything back properly it looks like there's a shared ground between the wiper motor switch and the park/neutral switch, after following that lead from the wiper through the fuse block. Since I'm closing in on bi-focal age, I won't swear to that, though.

[Bullitt-]

That is the "Low speed Torque Limiting Resisttor" and connects to the low teminal of the wiper switch. note says swwitch myst be grounded.  Ths appears to be similar to the balast resistor but I see no "value" for it, but if tests open i', sure it's bad. Re: sared ground, I don't see it that way. In the Schematic the lines run next to each other, you may be getting off line, look again.   Check if that wire that runs to the stater relay is on good.

[ChallengerHK]

Thanks for the info, Bullitt. I'm going to try to get out tonight and play around with all of this. I'll report back one way or another.

[MyMopar]

I'm sure you have thought of this but just wanted to post it.  If it isn't even turing over, have you tried starting it in neutral?  If so I 'd imagine the same thing happened then.
Did you check the starter for a loose connection, they can loosen over time and perhaps yours did?  On my Charger, I had a similar problem, sometimes it would start right up, other times, it would turn over slowly and then not at all.  Turns out that the harness that plugs into the back of the switch was melted and loose and that is why I would get errant start times.

[MEK-Dangerfield]

Do you hear anything at all when you turn the key? If you hear a click, then I would suspect the starter, or a bad connection to it. If you don't hear a click, then I would say your starter relay is out to lunch. If you suspect the starter, give it a few taps with a big screw driver, that might bring it to life. At least that would narrow the problem area. Strange that this would pop up when changing the wiper motor.  Another question... when you turn the key to the "on" position, does your radio or turn signals work?

  Mike

[ChallengerHK]

Problem solved. As I was running down wires I found that one lead on the starter relay was fitting very loosely. I squeezed it with a pair of pliers and the next thing I know the motor is running.

I know I wasn't anywhere near the relay, but I'm not going to think about that because it makes my brain hurt.

Thanks all for the help.

[MEK-Dangerfield]

 

[Bullitt-]

Glad to hear you got er fixed, Amazing how it usually turns out to be something simple. 

[RusTy/SE]

As i'm learning on my Coronet, the electrical system will present the most elusive issues to locate. Good going ChallengerHK