I have a 2003 Chevy Impala that has been blowing a fuse (the door locks fuse) on and off for about a year. We have replaced the fuse more than 10 times since July 2009. Recently, the car has begun occasionally not starting. There is no sound when we try to turn the car on and the radio and lights usually come on. The car will start maybe 2 hours later and run without any problems. We have had it in the shop separately for the fuse and for the not starting issue but they were unable to find any problems with the car either time. The last time (two weeks ago) they kept the car for a week and tested the electrical system but said it tested okay. 24 hours after bringing it home, it did not start but again 2 hours later it started up fine. No warning lights come on each time the car doesn’t start but at times Security, Service Vehicle Soon, and the Battery symbol have all flashed and then gone off. We have avoided using the remote key entry as that is when the fuse tends to blow and the car has been fine for almost two weeks now. Does anyone know if the remote entry could be part of the problem or have any other ideas on what could be making the car act up? Thank you for your time and input.
You have already established commonality.
You have a dead short somewhere. You keep blowing the fuse protecting the circuit involving the door locks. Further, you noticed that the fuse blows most often when you use the remote entry function.
Therefore you have a dead short in this specific circuit. An ordinary mechanic can’t help you, you need to find one that specializes in electrical systems and tell him or her what you have told us.
Thank you for your response. We had assumed electrical issues but when they said they had tested that and everything was okay we began to question that assumption. We will try to find a specialist tomorrow.
We had the same problem with our Impala not starting. Had battery, alternater and electrical system check as well. Like you, no problems found. Then the door locks and trunk release quit working. Security light came on and I could not find the problem. Like you, we used the manual key entry system for a long time. The car has not had a starting problem but now I am getting the check engine light (CEL). Bought a OBDII Code reader and found the PO481 code which points to the #2 fan control relay. Replaced the 25 amp fuse and cleared code and light went out. Also replaced the 20 amp door lock fuse and that worked for a few days as well. Then both went out again.Replaced both again but the fan is out again.Checking on that problem now. Good luck with yours. Would appreciate a post if you get it fixed. I will post if I find out anything more.
From your description of the trouble it sounds to me you have two seperate problems. The no start issue points to a connection problem to the main power bus. Clean your battery connections and look for a bad connection between the battery and the main power panel under the hood. If those areas are ok then check the ignition switch for a problem.
For the short problem I would suspect the trouble is in the door jam, most likely the driver’s side door since it is used the most. The wires in the door jam tend to break over time due to the flexing of the wires when the door opens and closes. Sometimes the power lead can come in contact with the ground. Since the fuse blows when the system is used it means the short is in the wire connections to the lock solenoids.
The fan problem you are having may be due to a bad fan motor. Try disconnecting it and then see if the fuse blows or check the current draw on it.
The door lock issue may be the same thing as mentioned above.
Thanks Cougar, I went out after the post and tried to manually spin the fans. One would spin and one was really stiff and made a noise when I forced it. Went to auto parts and purchased the whole assembly. Spent all afternoon getting the old one out… not an easy task. Had to remove the front motor mounts, battery and cross bars to get access to the assembly. I can sure see why they want big bucks at the dealer ship for this job. Anyways, got it all put back together and it came up running like new. Surprise, no left over parts! Next time it is research the door locks. Thanks for that tip on the door jam.
You’re welcome for the help and thanks for the feedback.