Chrysler Repair: 98 Caravan electrical issue: relays clicking, fuel pump relay, grand caravan


Question
QUESTION: Hi I've got a 98 grand Caravan with 140,000 miles. Last summer it left my daughter stranded after returning from a store. When I got there it would not start but sputtered and stopped cranking abruptly, and was making weird clicking noises. As i was trying to figure out what to do after several tries, I forgot to turn the ignition switch off and after about a minute the clicking stopped, and the van started right up. I drove it for about 3 months without incident, then it did it again.
I remembered that leaving the ignition switch on allowed it to stabilize and this worked again. Several more months, and same scenario.
Now I have the problem all the time, so i really started looking for it. I found that when I turn the ignition switch on, the ASD relay, fuel pump relay and EGR solenoid all chatter, with the fuel pump randomly turning on & off along with the relay, and the check engine light is on, but flickering in unison with the chattering relays. When I turn the ignition switch off, the chattering continues on the ASD relay and the EGR solenoid, but the fuel pump relay stops.
The battery voltage was low 11.6 so I replaced the battery. I checked the ground circuit from the negative battery to the relay pin (either 30 or 87) one was 0.0v while the other was 12.6 with the ignition switch on. I jumpered pins 30 & 87 and on the fuel pump relay the pump ran continuously while the other 2 components continued to chatter. Same thing with the ASD relay jumpered. With both relays pulled and the ignition switch on the EGR solenoid still chattered.
So far, in addition to the battery, I've replaced the igniton switch, the relays, the EGR solenoid. I have a code reader on order, but can't get any codes from the switch because the light continuously flickers. Below is a YouTube video:
http://www.youtube.com/watch?v=GQEmHRWRhCs

Thanks in advance!

ANSWER: Hi Wade,
We were dealing with this at the beginning of the month. My main thought is that when relays click like that it is because the voltag across the pins of the actuating coil is not a full 12.7 from the battery at that moment, so please compare the operating voltages of all the involved relay operating coils as well as what is actuated but not clicking when this is going on and lets get some numbers. Once we have that maybe we can figure out why this happening. With such readings I am at a loss to be sure of my theory on relay clicking.
Roland

---------- FOLLOW-UP ----------

QUESTION: Yes, since we last spoke I've done quite a bit of work, all to no avail.

I just pulled the fuel pump and ASD relays and checked voltage with the ignition switch on. I have a new battery now, but the car hasn't run to charge it fully. The first test I tried I got 12.4 volts between pin 30 and 87. I also got 12.4 volts on pin 86, but 0.o v on pin 85. This was for both fuel & ASD relays.

I then put a battery charger on the battery and set it to 10 amps. after a few minutes i repeated the test. This time i got 13.3 volts every place I had previously read 12.4 volts. With the extra voltage I turned the switch off, plugged the relays back in and turned the ignition switch on again. There was no change, everything is still chattering away.

As far as "what is actuated but not clicking" I'm not sure what else is actuated with the ignition switch on. Perhaps you can give me some direction. There is an EATX relay that is the same size and then several larger relays, all in the same location.

Answer
Hi Wade,
Try charging the battery overnight with an initial charging rate of 2 amp (if your charger allows you to pick the current flow, otherwise just let it charge at whatever the battery wants to 'draw' from the charger). That way we know you have a fully charged battery.
The other items that are drawing current while the ignition switch is in the 'run' position are:
the trans control module which is powered by fuse 15 in the power box and fuse 2 in the cabin fuse box, the trans range sensor via fuse 12 in the cabin fuse box, the generator field coil so unplug the dark green wire at the generator, the evap system which is powered by positive temp coeff #1 (a fuse-like device in the fuse box under the dash located in the row just below the 4 large plugs), the ASD relay for about a second or so when you turn the key to run. So try removing each of those fuses/devices/relays/specific plugs One at a time and notice whether any of them alone when removed stops the uncontolled clicking.
Please rate my answer (see PS below).
Thanks,
Roland