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2005 chrysler 300 blower motor

Printed From: the12volt.com
Forum Name: Car Security and Convenience
Forum Discription: Car Alarms, Keyless Entries, Remote Starters, Immobilizer Bypasses, Sensors, Door Locks, Window Modules, Heated Mirrors, Heated Seats, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=111418
Printed Date: May 09, 2021 at 5:30 PM


Topic: 2005 chrysler 300 blower motor

Posted By: bgraper
Subject: 2005 chrysler 300 blower motor
Date Posted: February 08, 2009 at 6:34 PM

Alright, just a little background to start:

I installed a remote start to this car around Christmas and it worked fine from the first start attempt...no issues. This past weekend, my large 8 gauge power supply wire (to a fuse panel that I installed to fuse all of my relays) was rubbing against the brake constantly and it wore through the shielding. The car filled with burning plastic smell, I cut the supply wire until I could figure out what was wrong.

I removed all relays and opened them to see if they were burnt. They were not.

I was driving the car around and everything worked fine except for the gauges (I believe it was supplied by the normally closed side of one of the relays I removed).

I spotted the problem, cut my supply wire where the burn was, luckily I had enough slack to just pull it forward a little bit.

I placed the relays back into positions and remote started. Everything again worked fine.

The blower now does not work. It worked the other day with the relays removed (tried that again today...makes no difference)....BUT the A/C button lights up with the blower speed switched to something, along with the rear defrost button (all on the same unit).

Any advice? I checked the fuses and they tested fine.

Also, it is the same whether I remote start or start with the key.



Replies:

Posted By: loneranger
Date Posted: February 08, 2009 at 8:28 PM
  • Was the 8ga power lead routed properly?
  • Why did the power lead burn, if it was properly fused?

It could have been worse. The power lead could have blocked the brake pedal and caused serious injury.



-------------
Ideal - cmon dude, add to topics in a useful manner, not stuff that is obvious.
Story - Phzzzt! Hey, what happened?! ... Isn't it obvious?
Moral - Never dismiss the obvious.




Posted By: bgraper
Date Posted: February 08, 2009 at 8:43 PM

The wire had lots of slack, but was very stiff because it's so thick. It was resting against the brake pedal and the constant back and fourth movement between them caused the insulation to wear down and it eventually broke through and grounded out against the metal of the brake pedal.

It's routed to the battery through (actually beside the grommet....couldn't get it through), fused at the battery with a 60A (now...it wasn't fused before because they were out when I purchased).





Posted By: ckeeler
Date Posted: February 09, 2009 at 5:02 PM

it sounds like a bad blower motor resistor. but what you should really do so you will know.... is remove the power plug from the blower motor and test it for voltage. if you have voltage there you have a bad motor. no voltage then test at the resistor, if you have power in and none going out, you have a bad resistor. no voltage going into the resistor then post back, as we will have to do some digging to find the problem.





Posted By: bgraper
Date Posted: February 09, 2009 at 5:32 PM
I downloaded the service manual and have been going through the wiring schematic.

All the grounds measure with resistances. The fuse tests fine.

The fuse is not getting any power however. I'm pretty sure the problem is in the "RUN RELAY" but my service manual does not specify which is the run relay. It only calls out fuses.


Which one is the run relay??

posted_image




Posted By: ckeeler
Date Posted: February 09, 2009 at 5:42 PM

i believe its this one. it will be marked "4727370AA" right on the relay.

posted_image





Posted By: bgraper
Date Posted: February 09, 2009 at 6:27 PM

There are 4 of them in the front relay centre.

A few more in the rear realy panel.

Do you know which it is? Do you know a good way of testing them? Other than applying a +12V and seeing if it switches from Normally Closed to Normally Open?





Posted By: loneranger
Date Posted: February 09, 2009 at 8:47 PM

In your diagram, there should be another fuse before the relay.



-------------
Ideal - cmon dude, add to topics in a useful manner, not stuff that is obvious.
Story - Phzzzt! Hey, what happened?! ... Isn't it obvious?
Moral - Never dismiss the obvious.




Posted By: bgraper
Date Posted: February 09, 2009 at 8:55 PM

It is fused before it reaches the load.

That picture is straight from the 7500 page sercive manual from Chrysler. I took a snapshot out of a pdf. I did not draw it.





Posted By: loneranger
Date Posted: February 09, 2009 at 9:06 PM

bgraper wrote:

It is fused before it reaches the load.

Read my reply again. I said "before the relay", in other words, between the battery and the relay. I'm pretty sure is wasn't designed, without protection to the wire feeding the relay.



-------------
Ideal - cmon dude, add to topics in a useful manner, not stuff that is obvious.
Story - Phzzzt! Hey, what happened?! ... Isn't it obvious?
Moral - Never dismiss the obvious.




Posted By: bgraper
Date Posted: February 09, 2009 at 10:13 PM

I know what you meant, and I agree because that wire runs from the relay in the front to the power distribution panel in the back...if it were to ground out there would be no fuse to trip potentially (according to the service manual).

Update --> I found the relay that feeds the rear distribution center. Across the relay the coil is seeing +12 V all the time, it is never getting the ground signal though.

Everything from the relay back checks out okay. There is nothing wrong with the system itself....it's just not getting the signal to turn on.

Does anyone know where the -'ve signal for the relay comes? Is it from the key? If it is then I at least know if could be my remote start.





Posted By: a137
Date Posted: February 17, 2009 at 3:25 AM
It might be more tricky, than a relayIf you have climate control, blower motor is fed not through resistor, but via CAN bus operated electronic switch circuit.It's attached near the motor and has a heatsink. Has a size of cigarette box. To find the module just follow thick green wire from the motor itself.I had a similar issue on my Grand Cherokee 06. After disconnecting and reconnecting some big socket under the dash blower motor stopped working.Beleive or not it recovered when I mistakenly grounded heatsink to metal brace. Got a spark and working motor.I think some CAN bus interface IC in the module was in "frozen" or "suspended" state and was reinintialised after "electroshock".

This is not a guideline, I think it was a happy coincidence, however try to disconnect a battery for some long period (couple of hours) during this time find, disconnect and reconnect blower motor control module.





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