: Security System Problem



DopeStar 156
03-20-09, 10:54 PM
Out of no where my alarm went off outside and now the SECURITY SYSTEM light on the dash won't go out. I soaked all the switches with WD-40 and still nothing. I took the little black cover off the self lowering mechanism and soaked everything and it seems to be setting off the alarm when I close it but still the light on the dash stays lit. What do I do to fix this? This thing is gonna blink all night and kill my battery.....

Cadillac_Fan
03-20-09, 11:44 PM
Have you checked all fuses? The theft deterrent system uses voltage through five fuses:
1. IN-LINE FUSE A
2. IN-LINE FUSE B
3. LTR FUSE
4. BODY FUSE
5. GA-TRANS FUSE (when ignition is turned to "RUN")

According to my 1988 Brougham FSM: The SECURITY SYSTEM indicator illuminates when ground is provided by the theft deterrent controller. When the controller senses no voltage from the GA-TRANS FUSE (w/ ignition switch off) and any door jamb switch is closed (door open), the indicator should flash on-and-off (indicating system is unarmed).

Is your illuminated entry working properly? It sounds like a bad fuse. I'd think if it was a door jamb switch, your interior lights would be affected, as would illuminated entry.

Cadillac_Fan
03-20-09, 11:50 PM
I should mention the "Theft Deterrent Controller" is mounted on the RH side of brake pedal support.

DopeStar 156
03-21-09, 12:11 AM
Thanks for your quick reply. I found a relay in the trunk when I disassembled the black box for the power pull down, it looked fine. The second I know of is in the fuse box behind the parking brake pedal and since that one also controls the radio and a few other things that still function, I assumed that one is fine too. Where are the others located?

My illuminated entry works normally but that's controlled by a separate jamb switch. There's big thick black ones that control the Theft Deterrant system so I believe. The car starts and runs normally, the SECURITY SYSTEM light disappears when the key is turned to RUN but stays on with the key off and out. Doors opened or closed that light stays lit, or blinks, depending whether or not I locked the doors.....

Is it possible that control thing near the brake pedal died?

I put the car in my garage for safe keeping, I'm a little scared somebody may have ****ed with it even though it's unlikely since I live in the stix.....

sven914
03-21-09, 12:20 AM
I have the Theft Deterrent System diagnostic procedure for my 89 Brougham. I suggest that if your planning on repairing your own Cadillac, that you acquire a Cadillac Factory service manual. Here are several on eBay (http://shop.ebay.com/items/?_nkw=1989+Cadillac+brougham+service+manual&_sacat=0&_fromfsb=&_trksid=p3286.m270.l1313&_odkw=1989+Cadillac+brough+service+manual&_osacat=0); the white ones are the OEM Manuals, and the same as what I have.

The Diagnostic and repair procedure is as follows: The first thing you have to do is acquire a 12 volt test lamp and a Digital Volt Ohm Meter (DVOM).

1. Sit in the passenger front seat with all doors closed. Reach over and turn the IGNITION SWITCH to RUN and back to OFF. Open the RH Front door and lock it. Close the RH Front door and wait 5 seconds. Pull up the RH FRONT DOOR LOCK CYLINDER and open the RH front door. If the horn and lights come on, continue to step 2. If they do not come on, skip to step 5.

2. With the alarm still going off, turn the ignition to START. If the starter does not operate, continue to step 3. If the starter does operate, skip to step 13.

3. With alarm still going off, get out of vehicle and turn the door lock to UNLOCK using the key. If the alarm stops, continue to step 4. If the alarm does not stop, skip to stop 16.

4. Turn the ignition to START. If the starter operates, the system is operating normally. If the starter does not operate, skip to step 21.

5. Backprobe THEFT DETERRENT RELAY (my book only describes it as being on the RH side of the brake pedal support) connector with a 12 volt test lamp from cavity A (I woulds assume the go in alphabetical order from right to left) to chassis ground. If the lamp does not light, then repair open in IN-LINE FUSE A or the BLACK/YELLOW wire that runs from the in-line fuse to the theft deterrent rely and controller. If the lamp lights, continue to step 6.

6. Backprobe theft deterrent relay with a test lamp from cavity D to chassis ground. If the lamp does not light, repair open in IN-LINE FUSE B or the DARK GREEN/WHITE wire that runs from the fuse to the relay. If the lamp lights, continue to step 7.

7. Connect a fused jumper from relay cavity F to chassis ground. If the horn and lights operate, remove jumper and continue to step 8. If the alarm does not operate, check wiring from the relay to the horns and lights; if wires are good, replace relay.

8. Disconnect the relay and the THEFT DETERRENT CONTROLLER (it is attached above the relay) connectors. Connect a digital Volt OHM Meter (DVOM) from relay connector cavity F to controller connector cavity F. Set the meter to read resistance (OHMs). If resistance is less than .003 OHMs, reconnect relay and continue to step 9. If the resistance is greater than .003 OHMs, repair open in the BLACK/WHITE that runs from the relay to the controller.

9. Backprobe the controller with a test lamp from cavity G to chassis ground. Press the door lock switch to LOCK. If the test lamp lights, continue to step 10. If the test lamp doesn't light, check the power door lock operation. If good, repair open in the LT BLUE wire that runs from the door lock switches to the relay, or the open in YELLOW wire that runs from the LH FRONT SEAT SWITCH to the controller.

10. Disconnect the controller connector. Connect a test lamp from connector cavity N to chassis ground. If the test lamp lights, continue to step 11. If the lamp doesn't light, repair the BLACK/YELLOW wire (mentioned above).

11. Connect a DVOM from controller connector cavity A to chassis ground. If resistance is less than .003 OHMs, continue to step 12. If the resistance is grater than .003 OHMs, repair the BLACK ground for the controller.

12. Connect a DVOM from controller connector cavity J to chassis ground. Measure resistance with the RH doodr open. If resistance is more than .003, repair open in the LT BLUE wire that runs from the controller to the door jamb switches, or replace the door jamb switch. if resistance is less than .003, replace the controller.

13. Disconnect the controller connector. Backprobe the starter interrupt relay (above the lower base of the steering column) connector with a test lamp from cavity 5 to chassis ground. Turn the ignition switch to RUN. If the test lamp lights, continue to step 14. If the test lamp does not light, repair open in the PINK wire that runs from the ignition switch to the starter interrupt relay.

14. Disconnect the starter interrupt relay connector. Connect a DVOM from the relay connector cavity 2 to the controller cavity E, measure resistance. If the resistance is less than .003, reconnect the relay and continue to step 15. If the resistance is grater than .003, repair open in the DARK BLUE wire that runs from the relay to controller.

15. Connect a fused jumper from the controller connector cavity E to chassis ground. Turn the ignition to START. If the starter operates, replace the starter interrupt relay. If the starter doesn't operate, replace the theft deterrent controller.

16. Disconnect both the theft deterrent controller and the theft deterrent relay. Connect a test lamp from relay connector cavity A to cavity F. If the test lamp doesn't light, continue to step 7. If the lamp lights, repair short to ground in the BLACK/WHITE wire (mentioned above).

17. Connect a DVOM from the controller connector cavity H to chassis ground. UNLOCK the door with the key. If resistance is less than .003, continue to step 18. If the resistance is more than .003, repair the LT GREEN, DK GREEN wires that runs from the controller to the door lock cylinders, or replace the door lock cylinder switch.

18. Connect a test lamp from controller connector cavity K to chassis ground. Turn the ignition switch to RUN. if the test lamp lights, continue to step 19. If the test lamp doesn't light, repair the open in the PINK/BLACK wire that runs from the fuse block to the controller.

19. Connect a DVOM from controller connector cavity J to chassis ground. Close all doors and trunk and DO NOT sit in the driver's seat. If the resistance is more than .003, continue to step 20. If resistance is less than .003, repair short to ground in the LT BLUE, TAN, GREY wires, the THEFT DETERRENT DIODE (all are part of the door lock circuit), door lock cylinder switches, door jamb switches, or the trunk lid tamper switch and check the YELLOW wire (mentioned above) if equipped with auto door locks.

20. Connect a test lamp from controller connector cavity G to chassis ground. If the test lamp does not light, replace the controller. If the lamp lights, repair short to voltage in the YELLOW or LT BLUE wires (mention above).

21. Disconnect the controller connector. Turn the ignition to START. If the start operates, replace the THEFT DETERRENT CONTROLLER. If the the starter doesn't operate, then the problem is in the starting system.

I'm not sure which step will fix your specific problem, but if you follow this procedure your probably going to come across it (and maybe some more).

Cadillac_Fan
03-21-09, 12:28 AM
Your Brougham appears to be heavily optioned. Do you have central automatic door locks and fuel door lock, too?

Nonetheless, IN-LINE FUSES A & B are "behind I/P, above steering column" according to the FSM. (Naturally they'd make them a b!tch to access.) To add insult to injury, the FSM does not give a branch in the diagnostic tree for a "SECURITY SYSTEM" warning indicator that will not stop flashing.

The FSM states: "When the system is armed, any one of four actions triggers the alarm by grounding the 263 Tamper Input circuit: 1) opening any door; 2) tampering with trunk lock cylinder; 3) tampering with either door lock cylinder; 4) occupying the driver's seat." (There is a switch embedded in the top of the driver's seat.)

If it tells you anything, the FSM has 8 pages of diagnostics for the Theft Deterrent System, alone.

DopeStar 156
03-21-09, 12:36 AM
Yeah I have the '89 FSM and you're absolutly right, it mentions nothing in its diagnostic proceedure for what to do if the ****ing light won't go out. A majority of my problems that I've had with this car have proven that the FSM is no more than fire kindling at best.....

My car has power door locks and the option where they lock/unlock when the car is shifted into Drive/Park if that's what "Central Automatic Locks," means. It also has the fuel door lock in the trunk. I did notice however that there was a metal component bolted into the trunk latch which was kinda loose, I tightened it and saw no difference in activity......

DopeStar 156
03-21-09, 07:31 AM
Well I thought maybe overnight something would just pop back into place, but no success. Car's running right now and I'm gonna drive it to work. I'm completely outta ideas now......

csbuckn
03-21-09, 08:18 AM
Your probably gonna have to do the diagnostic that sven914 posted for you. I know its long but it should tell you exactly whats wrong.

DopeStar 156
03-21-09, 06:48 PM
Went to work today and spoke to a connection I made who was a Cadillac mechanic from the late 70's to the late 80's (pretty much worked on one style of RWD, haha) and gave me some helpful diagnostic suggestions not to mention an explaination of how the Theft Deterrant system works. This was the same guy who rebuilt my heads and is solely responsible for the phoneminal way my car starts, runs, and drives.

Turns out the "metal component" on the trunk lid is the lock cylinder tamper sensor which is what monitors the trunk, not the switch which works the trunk ajar light and the power pulldown. This was the thing I said was loose last night which I tightened. There's one black wire going to it with a plug, turns out that plug had come loose too, prolly from the thing floppin' around in the trunk. Tightened up the connection and voila, the light went out and the system arms as it should.

Thanks for the replies, especially the ones at 11:45 PM.

Cadillac_Fan
03-21-09, 11:35 PM
Great to know you got it resolved. Moreover, it must be nice to have a valued resource in the tech who's worked on and knows your Brougham well. You genuinely have one of the best. (Man alive, I miss my '88 Brougham - oil burning, rust, and all...)

DopeStar 156
03-22-09, 10:22 AM
Well I spoke too soon. Turns out I was way off mark but I'm gonna correct myself so others can use this thread for reference....

The thing I was just talking about was the remote trunk release that's controlled by that yellow button in the glove box, I found the real problem and it's on the lock cylinder. I had to take the trunk latch off to get to it and I saw the single metal cable that connects to a two prong plug with a black and light blue wire. I just unplugged it to disable it so now my trunk is no longer protected by the Theft Deterrent system.....

I think the only way to fix this would be to replace the whole lock cylinder which would mean I'd have three keys to my car and I'm not that concerned. It only happens when it's 40* or below outside so I've just decided not to worry about it. I've got one last idea and that's to spray liquid wrench inside the lock (where the key goes in) to eat any corrosion that may have found its way in there. When the temperature starts to stay consistently above 50* then I'll consider reconnecting it.

Sorry for all the mass confusion........

dill
03-22-09, 06:13 PM
I took the light out of mine to prevent the battery from going dead,until I get it fixed.