My 2008 unlimited suddenly will not start. I'm fairly mechanical but this one is giving me trouble. Difficult to search this out on google cause the symptoms are so generic..

Symptoms

1. Starter not engaging - no click at all
2. Headlights are on bright - don't dim when trying to start
3. Most notable symptom
4. Accessory power drops went key is turned over.
5. Radio , AC fan dies, this power cuts out for 30 seconds or so then turns back on.
6. Cant not shift out of park.

UPDATE.
I have red lighting bolt, ETC light, comes on when key is turned on , it stays on about 10 seconds after all the other light test go out. Then the engine light blinks 10 or 11 times..

Troubleshooting

1. battery measures 12v
2. checked all cables are tight, not corroded
3. tried jumper cables
4. no notable codes
5. tried swapping some relays around, starter relay
6. checked , re-seated 60amp main fuse
7. manually jumper'ed starter solenoid and it cranks good..
8. tried my spare key also , testing possible key fob issue
9. verified gear selector on dash does indicate its in park, I also did the shifter override to try starting in neutral

thanks in advance for any input. it seems the loss of radio and fan power is related to the problem..

Curt

 

Etc, Red lighting bolt indicator on dash. Stays on for 10 seconds after the other light test finish. Then engine light blinks 10 or 11 times..

 

My recent problem may have some relation.

My 2008 has factory installed remote start. Last week, my key-start was doing nothing. There had been some times previous when I thought the "start" didn't feel quite right, but I figured the car is just getting older. I've had the problem of having to fiddle with the gear selector to get the ignition to work for years- that didn't help this time, nor did putting it in neutral As usual, I was off in the boonies, so I just kept trying the key - then I realized I could start it with my remote starter. That's what I did for the next few days.

Now, things seem back to normal. My gut feeling is the problem is the ignition is bad. Frankly, between the three electric systems - ignition, remote start and the gear shift lockout - I'm not willing to pay $95. a hour for my garage to play around with it. I don't recall anyone posting about similar problems, but ours may be the start. For now, I'm happy i have the remote start system.

 

Check the voltage with a DMM at the battery wire lugs (not the terminals) while someone else turns the key. You want to measure the voltage during the key-on to check for bad connections and bad battery. The voltage should stay greater than ~11 volts.

 

Did you check for any codes? Maybe there is a clue there.

 

Batteries....

There is a difference between Volts and Amperes. Volts is like the pressure on a water hose (PSI), Amps is the Gallons per Minutes. Together, they make Watts. Watts is what you need, that is why is so important. So, the number to look for are CCAs (Cold Cranking Amps) on a battery. The higher the Amps, the stronger it is. Your battery might have some dead cells, that is just borderline to crank the engine, but provide enough power to run all accessories like nothing happens. Jump it, see what happens, I bet it will start.

Now days with the swing on temps from cold to hot batteries have the tendency to fail. Last weekend mine did, out of the blue. Looks like all was fine but a small click when you try to crank the engine. To our luck, was across the street from an Auto Zone. Now with a replaced battery, is good as new.

Places like AZ can load test the battery for free, most likely you have some dead cells. If is under warranty, replace it for a nice discount. An OEM bettery last about 5 to 6 years without a tender, about 11 with a tender.

 

It is odd that the lights are on and do not dim at all when trying to start. I usually think the starter isn't engaging at all. I think the OP said when he jumps across the starter the jeep starts up. I just saw that there were no codes either. I know the FOB can cause some odd things even though the spare key also didn't work. A weak battery in the FOB can cause weird things or it could be anything from the ignition to the actual starter (I think the starter relay is part of the starter but not sure). You may have to check to see if your getting the voltage to the starter when the key is turned and work your way back. Let us know what you find.

 

Well, could be the part that engages the starter, but if is bad, the Starter will spin on its own. A battery load test is free and easy to do. I would start there before throwing parts at the problem with the hope to find the issue.

 

Yes troubleshoot and test as much as possible before buying anything! There are several tests and simple things you can do right now to narrow down the problem.

 

I note in your OP.. no Notable codes.. Did you have a code reader? If no.. That would be a priority diagnostic check NOW; just IMO. Not sure that codes would show if the PCM is experiencing issues.