Crazy dash lights and oil light

dodge
caravan
electrical-wiring
oil
lights
gauges

#1

I drive a 2005 Dodge Caravan. Recently, my dash lights started acting crazy. I took it to my mechanic who guessed it might be low voltage, and put in a new battery. This seemed to fix the problem, and it drove fine for a few days. I took a trip to visit family and while on the trip my oil light came on. I should mention that when he put the new battery in he also did an oil change. We turned the car off, parked on level ground, and checked the oil. It was fine. Turned the car back on and the oil light did not come back on. Worried as I was, I took it into a mechanic where I was on vacation and had him look at it. He said it was the oil pressure switch and changed it. He also commented that oil was leaking around the switch? This did not solve the problem. It continues to come on, especially after the car has been off for a while. It comes on, and if I turn the engine off and start it right back up it does not come back on.

Additionally, the dash lights and dials are doing crazy things again. The other day while driving, the dials dropped to zero, then went all the way to the max, then back to normal. Then all of the dash lights came on and went off except for the seatbelt light which stayed on for a second and gave a little indicator “ding”, then it went off. It did this three times-identically. Made me kind of wonder if the car was posessed! LOL!

Anyway, seems to me that these are two different problems, but I am NO EXPERT my any stretch of the imagination. What do you folks think?

PS-I did read the one question and responses about the other dodge caravan’s crazy dash lights. I gather from that discussion that it could be a bad ground connection? But thought I’d mention it to see if there were any other ideas or if it might be connected to the oil light issue.


#2

I agree with the bad ground connection diagnosis. I had a similar experience with my s10. The ABS ground was sub-standard. ABS lights would flash and then everything would reset periodically, so I would see about the oil-light ground first then go from there.


#3

It is either bad grounds or a bad voltage regulator/ alternator. The battery fix will work for a little while if the volt regulator is bad. That is because the voltage does not stay high enough to charge the battery. The alternator should be removed and tested underload. The volt regulator is built in. The issue for grounds comes in due to the slight ohm impedance(increased by corrosion) that some sensors are sensitive to. Normal running volts on a car are 14-14.5 from the alternator. The battery fully charged about 12.5. If you have a voltage sensitive sensor the battery volts can run as low as 10.5 before your car cant start. So a voltage sensitive sensor that should work great at 12.5 - 14.5 volts is now seeing less than 12 due to a non regulating volt regulator. Add just a bit of corrosion and the 15% drop in volts is enough to start driving sensors wild. First test the alternator at a chain store of a mechanic. Next is chaseing the ground. It is easier to test the volts first because the source is the battery and the alternator/voltage regulator(They are one unit with two different jobs).