Mechanics

06 WON'T START WHEN WARM

2006 Jeep Liberty • 6 cylinder 4WD Automatic • 94,000 miles

My 2006 Jeep Liberty Sport 3.7L starts just fine in the morning and at night when the weather and/or vehicle are cool. During the day I turn the key and get one starter relay click and no starter cranking at all.
During the past 2 weeks or so I had noticed that the vehicle would not start until I turned the key all the way to the stop, rather than just past the detent where the spring loaded resistance begins. I eliminated the starter relay by swapping it out with one of the wiper relays (same part #). I am assuming that the ignition switch is good since the starter relay is activating. Pretty sure my battery is good since all electrical systems seem normal. I tried moving the steering wheel and the shifter to exercise the neutral switch. Is it possible that I could have a bad ignition switch and still be sending some juice (but not enough) to the relay?
Avatar
Justdoit8
May 28, 2011.




Suspect starter motor possible worn bushings. When it won't start get to starter put test light on small wire at starter have helper turn key if it lights every time the motor faulty.

Docfixit
May 28, 2011.
It started fine this morning, allowing me to drive it up on ramps.
I used the test light to probe the wire. No light when attempting to start. I tried all angles of the conductor (slide-on end of connector, and crimp end of connector). The thick red wire running down from battery lights up nicely as expected. I re-affirmed that the starter relay inside the PDC clicks on every start attempt.

Tiny
Justdoit8
May 29, 2011.
I re-traced all electrical connections again with a voltmeter. Everything seems to check out fine. I noticed in my Haynes repair manual that my Jeep has a battery temperature sensor located under the battery in the bottom of the tray. Sounds like a candidate for causing this type of temperature related failure. I removed the battery and set a bag of ice on top of the sensor for about 5 minutes. I then re-installed the battery and the vehicle started with no problem. Now I think I have it narrowed down to either the temp sensor or the battery itself. Maybe my battery is marginally functional?
AD

Tiny
Justdoit8
Jun 1, 2011.
Have a load test done on BATT local parts store will do

Docfixit
Jun 1, 2011.
I gave up and took it to my mechanic. They found that the ignition switch/steering column had a short in it somewhere. They had to replace the steering column with the switch.

Tiny
Justdoit8
Jun 10, 2011.

AD