QuestionQUESTION: Hello!
I'd like to start by saying I've been scouring this site for the past couple months trying to diagnose my problem, but haven't found another problem quite the same so I figured its time to ask. A couple months ago I bought my first car third party and it came with this problem (though I didn't know it at the time). They had told me they put in a new battery and a new starter; I should have seen the warning signs, but I figured they fixed whatever problem they had. It is a 1998 chrysler concorde lxi with the 3.2L engine
I'm no mechanic by any means, and this is my first jump into the car realm, but my dad is pretty experienced with cars, as is much of my extended family, and this one has them all scratching their heads. So here is what we have figured out so far:
When the car has been sitting awhile (it varies, sometimes 30 minutes, sometimes hours) and you turn the key to run you can hear clicking coming from the relays in the PDC. If you turn the key to start while its in this position nothing will happen. After awhile the clicking will stop on its own (although a couple times I've had it continue even when I pull the key out of the ignition. Another time I left the key in the run position and the clicking came back on its own 15 minutes later after it had stopped on its own.) While the clicking is happening you can hear the fuel pump engaging and the Idle Air Control being set, which is probably because they are on the same circuit. It almost acts like the computer is being reset and keeps doing the things it usually does once when the key is intially turned to run. The check engine light will also come on while its clicking, but will then go off when it stops. The computer doesn't store any codes from this. The only one it has is P1684, which makes sense since I've had the battery disconnected before. BUT, I feel like I have started it more than 50 times since then, which now has me wondering if the PCM really is losing power somewhere.
And then once the clicking stops and you start the car, it will often start, then die. It will do this a random amount of times (anywhere between 0 and 20) until it finally gets started. But then once the car has been started and driven it wont have any of these problems unless it sits for awhile. So a quick run to the store for 30-60 min and then back to the car, it often starts up without a problem. I've also had it die on me while driving twice. The first time it was right after I left the gas station, so I attribued it to bad gas. I was driving about 40 down a street and the check engine light came on a couple times and each time the car kind of jerked and then kicked back in. But as soon as I reached a red light and had to stop it died. (Again, no codes from the check engine light coming on and off). The other time was when I was leaving a friends house and it died on me at the first stop I made, and every stop I would make thereafter from there to my house.
I'm not sure what things here are connected into one problem, and what might be separate problems. I have the Haynes Repair Manual and have been using that this past couple months without much luck in finding the source. I finally took it to a mechanic the other day and he did a quick diagnosis for me and said he thinks it might be the ignition switch causing a drop in voltage. But I feel like if it was, wouldn't I be able to reproduce the problem by moving the key around in the ignition? And wouldn't the car die on me while driving and not only when I stop? However, I do tend to agree that there's probably a voltage drop somwhere, but I have no idea where.
I'm not sure if I'm forgetting anything else we might have done already, but I'll be sure to let you know if I remember. Anyways, any insight you could provide would be very helpful and appreciated. Thanks!
ANSWER: Hi Josh,
I believe it could one of two possibilities:
Either the ignition switch is flaky or there is an intermittent short in one of the circuits that is powered by the ignition switch that is dragging down the voltage of the system to the level that the relays will not stay closed due to too low an actuating voltage appearing on their actuating coils.
My suggestion would be to look at the battery voltage when the clicking is going on and compare it to the voltage that is typical, either after it has stopped or the last time you checked the battery voltage. Turning the switch from 'off' to 'run' should not produce a significant difference. If you see no significant difference then I would focus on the ignition switch to be sure that all the pins that are supposed to show voltage in the 'run' position are showing such.
Specifically, look at fuses 1,4,8,14 in the fuse box behind the dash (left hand end cap, remove for access) when the switch is in 'run' and things are clicking.
I suspect that a rhythmic clicking is due to a short circuit at that moment, and probably the best thing to do would be to remove those same fuses and determine what is resistance to ground (any shiny metal surface nearby to the fuse box) between each of the pins of those fuses when you have the ignition switch in the "off" position. You will find one pin of each of those fuses will show infinite resistance, but the other pin will show some specific low resistance but not a near dead (0 ohms) short. If you find one to be shorted let me know the number of the fuse and we'll go from there.
Roland
Roland
---------- FOLLOW-UP ----------
QUESTION: Hello again Roland, sorry for the delayed reply. I’ve been doing more and more testing the past few days. As for the tests you requested, the battery voltage seems normal in both cases. As for the fuse tests, my dad was afraid I would break his meter by doing the tests with the battery connected. So I had to measure the resistances with it disconnected. I’m not sure if that will affect the tests. On fuse 1 I had a resistance around 109 ohms, the rest of the fuses I had really high resistances, in the kilo-ohms. I’m not sure if that’s normal or if I did something wrong in the test.
However! I do have new information that may be of use. The clicking will always continue after it has started, whether I leave the key in run or take it out. The only thing that stops it (besides it “fixing” itself, which takes random amounts of time) is pulling the ASD fuse. I finally got my hands on some more detailed wiring diagrams and looking at that, the ASD fuse powers the PCM, so I guess it makes sense that it would stop it. And it does not resume clicking when I put the ASD fuse back in. Also, I noticed the PCM gets the signal from the ignition through fuse 13 (fuel pump fuse) which goes to the PCM and that fuel pump relay. So by applying power just on that fuse (and even taking the fuel pump relay out) the clicking will start. I should also mention that I can pull every fuse and relay in the PDC with the exception of the ASD fuse and Ignition run/start fuse, and the clicking will happen when I turn the key to run (I can put a light on the relays to see it pulsing). Once the clicking starts, I can remove and reinsert the Ignition run/start fuse without any effect on the clicking. And I’m bypassing that fuse altogether when I’m sending power through fuse 13 like I mentioned before. I checked the diagrams and saw that the ignition signal goes to pin 20 on the PCM, so I checked the signal there by turning the ignition on/off many times and the signal was always good. I also checked the power for the PCM (pin 46) and ground (pin 50) and they appear to be good. We also disconnected connectors C101 and C102 to practically isolate the PCM from any sensors and would just apply power to pin 13 on C101 (which goes to pin 20 on the PCM for ignition power), and still the clicking would start up. I’m still trying to figure out what I should test from here to try and narrow it down. Any ideas? Again, thanks for your help.
AnswerHi Josh,
One of the problems I see right off is that you are apparently working with the Haynes manual that applies to the '94-'97 and its wiring diagrams are out-of-date for your '98. So for example, fuse 13 doesn't power the pcm but rather it powers the stop lamp switch! The pin numbers at the pcm are ok, but just for clarity would you also tell me which size engine you have as that impacts the wiring diagrams as well.
Can you tell me now which relay it is that is clicking uncontrollably?
You might want to try and get a newer Haynes or at least some diagrams for the '98 model year.
With these clarifications perhaps we can get a handle on this.
Roland
