View Full Version : 99 Eldorado security system woes

02-07-05, 02:56 PM
I've posted this before but never got any responses.. here's another try.

I have a 99 Eldorado (Non-ETC). I have had the stock stereo replaced with a Pioneer head unit. I have also replaced all the speakers, and have added a subwoofer and an amp.

Things worked OK for three years. Occasionally I would get strange behavior with the alarm system not responding, but was able to get around the issue by turning on the key and then disengaging the alarm once I got power to the rest of the car. Here's the strange thing - big drops in temperature caused the issue. If the temperature varied more than 15-20 degrees during the day it would trigger the behavior.

I was getting an error code - B1553 which indicated that the EPROM for the BCM was corrupt. I have just taken the car to a local dealership and they replaced the BCM and found lots of corroded relays and such that they cleaned up. However, after dropping $1100 on the whole visit to the dealer, my problem persists. The dealer is placing the blame squarely on the stereo installer (big surprise). The issue according to them is that there is a drain on the system that causes the voltage to drop to 11.9v, which is what is causing the alarm to not respond to the remotes. They further claim that the most likely culprit is a bad ground to the BCM via the new stereo.

I'm about to take it back to the installer, but I wanted to know if anyone has ever run into this type of situation before, and how could it be rectified? Putting in the stock stereo is not an option any longer as it was the victim of a flood during the 3 years it was out of the car.

Logandiagnostic - any thoughts? I've seen your site and know you occasionally come by here and know you are a Caddie wiring guru...


02-07-05, 08:29 PM
What was the cause of corroded relays? Was this vehicle a flood car? If so that would explain everything. As far as a current draw it sounds like the dealer did not do the proper diagnostics to locate the source of the draw. It is a simple procedure to diagnos the problem. I would like to know the history of this vehicle.


02-09-05, 07:49 PM
hey Dan, thanks for the reply.

No, the car was never in a flood. I'm the first and only owner/driver of the vehicle.

I do live in MA and do LOTS of highway driving, so the combination of high-speed and salty roads are probably the reason.

Also, I did have a relay in the engine compartment fusebox literally go up in smoke on me once about four years ago. I had just pulled in my driveway, was walking in the door and I noticed smoke coming from the hood. I ran back, popped the hood and pulled five relays that were melting. The fusepanel did sustain some damage that I have repaired (cut away warped plastic and cleaned up the connections.) Things had been OK ever since that point. A year later I had the stereo installed and the problems began then.

However, the dealer did give the fusebox a good once-over this time around and they claim things "seem OK" now. Now that I've typed all that it's making me think that perhaps I should be considering replacing it... :D

Just a further update - the car is back in the hands of the stereo installer, who have pledged to me that they will fix the problem at no cost to me. I'll post the results when they get to the bottom of it.

02-20-05, 10:33 PM
I have experienced the same problem.
I have a 99 eldo esc 14,101miles. If I leave the car for any length of time (day or two) it will shut down the computer, key fobs will not work, when i start the car the alarm goes off, i put the key in the door (with car running alarm shuts off). I was thinking of taking it to the dealer after more of my stereo install. But for me i dont feel that it would be worth it, my vehicle is not a daily driver so it dosent bother me that much.

04-29-05, 03:13 PM
I Have Suffered With A Very Similar Problem That Appears To Be Inline With Your Problem. About 3 Months Ago I Started To Have Problems With My 1999 Cadillac Eldorado Etc (bought New). When I Would Try To Start My Car Absolutely Nothing Would Happen...electronic Dashboard Would Be Blank, No Engine Turning Over, No Instrument Lights, Nothing!!! I Would Take The Key Out And Try Again....still Nothing....then I Would Pump The Brake Pedal And Try Again And The Car Would Start....i Would Have To Reset My Clock At That Would Go To 12:00 Usually As The Result Of This Incident....the Car Would Start And Everything Would Seem Normal For Awhile And Then It Would Happen Again. I Took It Into A Friend's Auto Service And They Had It For 8 Hours...checking Everything Electrical....everything Normal Except One Reading Of A High Current Drain Of 130 Ma. That Appearred To Be Associated With The Heated Seats But After 10 Minutes It Went Away As Most Electrical Circuits In The Cadillac Shut Off After 10 Minutes Of Unattended Service. This All Started To Happen When My Battery Went Dead After 3 Years But Had The Battery Replaced. After Having The Car Looked At For Electrical Problems I Even Went And Bought A New Key At Cadillac For $45 Just In Case The Resistive Chip In The Key Was Causing Me Grief With This Problem. After Buying The New Key The Problem Appeared To Go Away For Nearly 2 Months....now It Has Started Up Again. If I Take It Into Cadillac The Labor Costs For Troubleshooting Will Be Very Expensive. In Addition I Just Had My Gas Gauge Go South And Now It Doesn't Read Correct At All....so I Cannot Use It To Determine How Much Fuel I Have Left In The Fuel Tank. I Understand That The Problerm With The Gas Gauge Maybe A Fuel Sender Card That Needs To Be Replaced But I Understand It Is Located Under The Fuel Tank So The Tank Needs To Be Removed. Is This Correct? I Am Wondering If The Security Alarm Problems Might Be Associated With My Bad Fuel Gauge Drawing To Much Current And Causing It To Not Allow The Car To Start. Any Thoughts Out There On That Aspect? The Car Must Have Known I Just Made The Last Payment On It After 5 Years In April 2005. I Have 87,000 Miles On It....running Performance Has Been Excellent....have Had The Water Pump Replaced,brakes And Tires And Batteries Besides Numerous Interior Defects/problems I Had To Deal With When The Warranty Was Still In Force. I Cahnge The Oil Every 3000 Miles Too.