Chrysler Repair: Chrys. 2005 - 300 Starter circuitry


Question
QUESTION: The starter shorted out internally and went to ground during a start cycle. A new starter was installed. Now I can not get 12volts at the solenoid  activation wire. Fuse 10 and 20 are fine but there is no activation of the starter relay. Owners manual does not indicate location of starter relay but does locate fuses 10 and 20. Also there is no clicking of a relay when ignition switch is turned to start position. Starter works if solenoid is activated with an external jumper.

ANSWER: Hi Bud,
The starter relay is in the integrated power module on the right side of the engine compartment in front of the strut tower. The relay is the third from the front on the outboard side of the module.
See if that relay clicks or not. If it does, then the relay points may be oxidized and you can borrow an identical relay to check that out. Otherwise the wire from the relay to the solenoid switch on the starter may be 'open'(see below).
If it doesn't click then I would remove the relay and check the pins at the 4 corners of the socket as follows:
jump 12v to the front outboard pin which goes to the solenoid switch of the starter
test for 12v at rear inboard pin which should be present all the time, coming from from fuse 20
test for 12v at the inboard front pin which should be present when you turn the key to the start position which passes current from the ignition switch through fuse 10.
check for continuity between the outboard rear pin and pin 38 of the #3 plug at the powertrain control module (black outside/'natural color inside) which is the grounding wire that activates the relay provided you are in park or neutral.
One of these test should determine where the problem lies. Let me know what you learn.
Please read the PS below and respond to it.
Thanks,
Roland

---------- FOLLOW-UP ----------

QUESTION: Hi Roland
Everything checks out except there is no power at the inboard front pin nor at the hot side of fuse 10 when the key is turned to start even though the start terminal (2nd pin) at the ignition switch energizes.  Is there some sort of permissive in that circuit, and if so where is it located and what would be the checkout procedure.
The other thing that I am not 100% sure about is if I actually had pin #38 on plug #3.  I know I was on the right plug but I could not be sure of the exact pin location.
Your help has been extremely helpful and bang on to date, I sure appreciate it.

ANSWER: Hi Bud,
The pin from the 'start' position at the ignition switch is #4 and the wire color is pink/dark green. It passes through a single disconnect along the way which is light gray and has 26 pins located under the dash behind the glove box (but I doubt that has been 'opened'/disconnected).
See if pin #4 of the switch is showing 12v in the start position or not. If so, then fuse 10 should also show 12v as should the inboard front pin of the relay socket which is directly connected to the fuse 10. The only 'permissive' of the starter circuit is P/N and is  handled by the pcm via the grounding wire which actuates the relay coil if there is 12v present on front inboard pin of the socket.
The grounding wire at pin 38 is in a corner of that plug and is dark green/orange (The plug has 38 pins).
Please let me know how it works out.
Thanks for the rating and nomination. The Allexpert site will 'count' up to 5 such nominations from a questioner to a specific expert so feel free to do it again if you choose.
Roland

---------- FOLLOW-UP ----------

QUESTION: Good morning Rolan
Pin #4 goes hot when ign. sw. is in start position but I get nothing on the inboard front pin of the relay nor anything at either side of fuse 10 location. I checked the gray 26 pin connector behind the glove box for tightness and corrosion and everything looks good. So I'm back to square 1, any ideas?
Regards, Bud

Answer
Hi Bud,
I see my error...the orientation of the integrated power module, and thus what I was calling in-board/outboard, front/rear is off by 90 degrees! BUT regardless of that you should have seen 12v on the fuse 10 when you turned the key to start. The 12v from the ignition switch should be seen at pin 20 of the 26-pin light gray disconnect on the pin/dark green wire so verify whether that is there or not when you turn the key to start. If it isn't then there is an open in the wire. If it is there then the wire from the other side of the disconnect to fuse 10 is open. It comes into the module on pin 24 of the light gray 26-pkn plug on the back side of it. It also could be open internally so check for continuity between that pin and the fuse socket hot side.
In the meantime here are what the test should have been:
rear outboard pin should show 12v all the time coming from fuse 20,
jump across from rear outboard pin to front inboard pin and that should cause the starter solenoid to close and the starter to run,
check for voltage at inboard rear pin when you turn the key to start (which comes from the ignition switch and through fuse 10,
and finally check for continuity from front outboard to pin 38 at plug 3 of the pcm.
Sorry for mistake in my orientation of the module. Now lets see what you find.
I will go back to my earlier answer and erase the error and put in the correct list of tests, but you will get a notice of a revised answer, so don't be surprised. I want to do that so other questioners won't be mislead when they read it in the future!
Roland

PS: Glad to learn from your rating/nomination comment that the problem is solved. I only wonder why the aftermarket remote starter (which you didn't mention earlier) stopped working? Was that possibly caused by the shorting out of the starter motor? I am pleased we could collaborate on this one. No need to respond if you don't have the time.