Jump to content
CaddyInfo Cadillac Forum

cooling fan driver circuit short


bankstar20

Recommended Posts

I recently got the trouble code for my 96 eldorado- P1660. the explanation from auto zone says- the ECM has detected an omproper voltage level on the output driver module for the cooling fan driver circuit. probable causes

1. open or short circuit in the driver circuit. 2. failed cooling fan relay.

My battery has also been dying overnight, whch leads me to believe there is a short somewhere, but my car knowledge is limited. if someone could point me in the right direction, i hope to fix it myself. any input would be greatly appreciated!

Link to comment
Share on other sites


First off, there is no need for Autozone. Your car has an onboard diagnostic feature. I think the relays are between the fans. Check them first. That said, low battery voltage will set all sorts of false codes and awaken the electrical gremlins to come out and play. Might need to replace the battery first.

Link to comment
Share on other sites

so thats what obd means!! as soon as the temperature gets above 5 degrees i'll check on those relays! but just fyi- the first night i unhooked the terminal so it would fire up in the morning, and it did. started doing this about 5 days ago, and after about the second day i've been having to jump it too. battery voltage drops to about 9 now. just got the battery about 4 months ago (could be defective?). so does that sound more like a battery issue? Thanks for the help Ranger!

Link to comment
Share on other sites

I recently had an alternator failure and when the battery votage dropped below 9.6 Volts, the DIC started acting crazy and all kinds of codes were being thrown. These cars do not like low voltage.

Not sure of your exact problem but check all the wiring and connections around those relays, then move onto the relay itself. Here is a picture of the fans/relays from a 2000 eldorado.

fans%20and%20relays.gif

Link to comment
Share on other sites

you have no idea how helpful that picture is! i've never really worked on my own car in depth other than minor stuff. i appreciate it!

Your Welcome, let me know if you need anymore pictures or diagnostic help.

Link to comment
Share on other sites

You might check for a voltage draw and if none found, then have the battery tested. If you are going to do your own wrenching a FSM (Factory Service Manual) by Helm Inc (NOT Haynes or Chiltons) would be invaluable. That is where the above diagram came from and it will have all the removal and installation procedures as well as trouble shouting and test procedures. You should be able to find one on Ebay.

Link to comment
Share on other sites

So i had the battery tested and it was toast! i guess i just assumed since it was so new that couldnt be the problem. i finally realized that if somethin was draining the battery, the voltage would've fell below the 9.6 volts it constantly fell to and stayed at. thank you all for all the help!!

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...