2007 Chrysler PT Cruiser:Engine Cooling Fan Comes ON with Engine OFF

Engine Cooling fan comes on all by itself

Fan comes ON and stays On till it drains the battery.

There are few possibilities that can cause this problem:


The cooling fan can only come on with the engine off because of a few reasons.

1) The very first possibility it could be an internal problem in the TIPM.

What is TIPM?

The TIPM is the module/fuse box under the hood that controls many electrical features, one being the cooling fan. If for some reason it was applying ground to one of the relay control circuits with the engine off then the fan would run.

2) Another possibility can be  wiring problem. If one of the relay driver wires between the TIPM and relays shorts to ground it will turn one of the relays on and run the fan.

3) And very much possible it can be one of the fan relays. There is a high and low speed fan relay mounted directly to the back of the fan shroud. If one of these stuck on then it would cause the fans to run with the engine off.

To start troubleshooting this problem i suggest to start by inspecting the wiring.
 If  wiring checks ok. No loose connection or no short anywhere,then try replacing the relays and see if that takes care of it. They're inexpensive and have a fair chance of repairing the problem.At our garage we have seen mostly the issue is weak relay,which needs replacing and such problem goes away.
 Otherwise the problem would have to be diagnosed through electrical testing at the time it's acting up.


Hope this helps.
Thanks.


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2006 Chrysler 300: Door ajar light is ON

FRONT DOOR DOOR AJAR LIGHT ISSUES:

The door ajar switches are integral to the front door latches.Its very common and very famous problem, noticed by many others too.
FIRST UNDERSTAND

WHY DOOR AJAR LIGHT COMES ON?

The ajar switch signal goes to the instrument cluster which also serves as the body control module. When the ajar switches close it applies ground to the circuit, the cluster sees this and turns on the interior lamps and the door ajar warning.

WHAT YOU HAVE TO SEE AND CHECK?

Inspect the front doors,are they closing properly or there seems to be difficulty to close the doors.Or there is any kind of blockage to the door area.
If your doors are closing properly, then unplug the door latch and see if warning light goes OFF or not.

Even after unplugging the latches doesn't turn the warning off then either the problem is internal in the instrument cluster or both of these ajar circuits are shorted to grounds somewhere in the wiring harness. The wires may be pinched or rubbed through on a grounded component, or it could even be from moisture in an electrical connector. There are many possibilities,check for all basics mentioned.


What you'll need to do next is check for a short to ground on both of these ajar circuits.If you find the ajar circuits are shorted to ground then unplug the cluster and see if the short goes away. If it does then the short is in the cluster and it will need to be replaced.

BUT, if the short is still there with the cluster unplugged then the problem is somewhere in the harness between the cluster and each of the doors.You will have to follow wire by wire to trace the faulty wire.
You can also use test light to check continuity to the wires. On shorted wire you will not get continuity.

This will help.
Thanks.