QuestionQUESTION: hi , my 99 I'm shut off on the highway and i pulled it over and tried letting it cool down for a few then tried starting it again. it started but shut off after only about 4 seconds. i had gas and i didn't know what was wrong. i had it towed and has been sitting for a while at my house. after the night it first happened. i tried starting it the next day and since then all it does is crank but no start at all. i talked to some of my friends that know a little bit about cars and in result changed the fuel pump, got all new spark plugs, & a brand new battery. after all that all it does now is crank but no start. i checked the code by turning it on and off 5 times and it gives me a "p 1684" code. any ideas??? thanks.
ANSWER: Hi Arianna.
Changing the battery (disonnecting it) causes a 1684 code that will go away on it own after 50-100 key cycles. It is possible that there is an electical 'open' that is causing the 1684 but not likely.
I am dealing with exactly the same issue with Diana, who has an '00 LHS, the same vehicle basically. Here is how I just responded to her:
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'00 Chrysler LHS/300m: no start
Question:
QUESTION: Car started showing slight "hesitation" when turning the key for about a week. Yesterday, same thing but then a lightly heard "thump" under the hood and now upon turning the key, the normal sound of trying to start is there, but it won't start. Any ideas? Thank you!
ANSWER: Hi Diana,
Try turning the key to bring out the fault codes from the engine controller that will give ua an idea. Turn the key:"run-off-run-off-run and leave in the run position" doing that in 5 seconds or less elapsed time. Then watch the odometer window of the cluster to see the mileage change to show 4-digit numbers preceded by a P. Let me know what you find.
Also, when you turn the key to run position listen for the fuel pump in the rear fuel tank to hum for about 1 second which is normal. If no sound at all listen from outside the car at the rear while a helper turns the key. It shoul just hum for a second or so.
Roland
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QUESTION: The number is 1684 P
The wind is blowing hard today, but don't think there's any sound from the back when in the run position.
Answer:
Hi Diana,
The 1684 is a code that says sometime in the recent 50-100 key off-on cycles the battery voltage was not connected to the engine control module. That often will be the case if the battery was changed or disconnected. If nothing like that happened, then there could be an electical intermittent "open" that is the issue. Typically though the 1684 happens because the battery is often disconnected when trying to fix something. So if you can't recall anyone dealing with the battery recently, then that code would prompt a check with a volt meter to be sure the controller is indeed getting its voltage source.
There are but two fuses that directly activate the fuel pump, and one of them is also involved with the starter motor, which is working. The other fuse is in the box that is hidden behind a cap on the left end of the dash. So remove that cap and inspect fuse # 13. That fuse too could be involved in activating the starter motor so it could be that you will find it to be OK. But if you find that the wire has broken (blown the fuse) then of course that would be worth replacing or substituting another fuse that is not essential in order to get the fuel pump to work. Ideally you would recall in the past that when you turned the key to the run position that you heard a sound that you no longer hear and that lasted for about a second, but maybe you didn't ever notice it.
If you can get someone to listen in the back seat for a sound coming from under the rear seat, or listen from outside near that area where the tank is located, for such a 1-second humming sound and if it isn't heard and the fuse 13 is good, then that would suggest that the fuel pump is the problem.
There is a fuse box under the hood on the driver side, long and narrow, mounted cross-wise, and if you open the lid look a fuse N to be sure that it is not blown as that one is also involved in powering up the fuel pump but not as directly as fuse 13.
If the pump is working and the fuses are good, then you have to check for spark and for actual fuel pressure to be present (not just the sound of the fuel pump). Other than having run out of fuel, there are no other no start causes that wouldn't cause there to be another fault code in addition to the 1684. Sometimes a component can fail without setting a code and that would have to be based upon measuring with a voltmeter.
So check the fuses, listen for hum, and let me know.
Roland
Please Rate my answer again but consider this time giving me a 'nomination' to be 'volunteer of the month'. Thank you"
So try this same approach. Let me know if you are doing these repairs yourself and whether you have a volt-ohmmeter. About the only other major possibility is that the timing belt has broken but that would normally cause a 0340 code which says that no signal is coming from the cam sensor. But just in case you could try looking through the oil filler cap to see if there are any sign that the gear train is moving when a helper cranks the engine over and if that doesn't allow you to see motion then you could remove a spark plug and test for compression.
Roland
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QUESTION: Ok that was helpful but my fuse 13 inside the dash is good but im not sure where fuse N is in the fuse box under the hood. I have the cap of the fuse box that tells me what each fuse is but none say "n".
AnswerN is for the autoshutdown relay, and it is in the front row of the double row of fuses and it is the one closest to the adjacent large fuses. It is 30A in size.
Do you hear the fuel pump run for a second as I described for Diana.
If the fuel pump runs, then the only other no start/with no codes item that may be causing this the exhaust gas recirculation valve being stuck ajar. I can tell you where to find that and try one approach to checking that out.
