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1984 C4 Security System (Won't Start)

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Old 07-01-2015, 08:46 PM
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Angel1000
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Default 1984 C4 Security System (Won't Start)

I just bought this Vet. The gentleman said the security system works, but he did not have the door key at time of purchase. He started it and said not to lock the doors. I drove it home and parked it for a week. I went to start it the other day, dead battery, or so I thought. I replaced the battery, still would not start. After much research I learned about the security system. "VATs" "Door lock Key switches/Green wires" "Starter Modules" and ... PELLET RESISTOR on ignition key. My ignition key has no pellet resistor and it looks as though there never was one!!


The security system will not turn off or disarm and as a result the motor will not turn over. The security light remains on and NOTHING I do will disarm it. Ignition on/off/on again. Unlock doors(s) with door key, etc. I tried all the little tricks and procedures associated with the VATS System.


Is this NOT a VATS system? Is there a different system in the 1984 C4? I ask, because 1) none of the tricks/procedures are working and 2) because there is no resistor on my ignition key.


I just read someone else's thread about the horn relay's working, or not, has something to do with the system (That was new to me). My horn does not work.


Does anyone have a 1984 with a factory security system that does not have a pellet resistor ignition key? IE: Just a regular key?


Any help will be much appreciated!
Thanks,
Angel
Old 07-01-2015, 09:11 PM
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Angel1000
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No replies? Hummm? I have never been involved in a "forum." Have I posted my problem in the wrong section? Wrong forum? Can anyone see this?
Thanks,
Angel
Old 07-01-2015, 09:20 PM
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antfarmer2
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Hang in there someone will be along. Poke around the search while waiting
Old 07-01-2015, 09:38 PM
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Found this for you


The #1 problem is typically the lock switches
#2 the door pins not grounding correctly
#3 The logic circut that leaves the lights on for a min or 2 on exit of the car ( does this work?)
#4 BAD horn relay
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Old 07-01-2015, 09:57 PM
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frank j. moran
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Originally Posted by Angel1000
I just bought this Vet. The gentleman said the security system works, but he did not have the door key at time of purchase. He started it and said not to lock the doors. I drove it home and parked it for a week. I went to start it the other day, dead battery, or so I thought. I replaced the battery, still would not start. After much research I learned about the security system. "VATs" "Door lock Key switches/Green wires" "Starter Modules" and ... PELLET RESISTOR on ignition key. My ignition key has no pellet resistor and it looks as though there never was one!!


The security system will not turn off or disarm and as a result the motor will not turn over. The security light remains on and NOTHING I do will disarm it. Ignition on/off/on again. Unlock doors(s) with door key, etc. I tried all the little tricks and procedures associated with the VATS System.


Is this NOT a VATS system? Is there a different system in the 1984 C4? I ask, because 1) none of the tricks/procedures are working and 2) because there is no resistor on my ignition key.


I just read someone else's thread about the horn relay's working, or not, has something to do with the system (That was new to me). My horn does not work.


Does anyone have a 1984 with a factory security system that does not have a pellet resistor ignition key? IE: Just a regular key?


Any help will be much appreciated!
Thanks,
Angel
84 and 85 have a regular key. The drivers side door lock arms and disarms the VATS. Hope this helps.
Old 07-01-2015, 10:04 PM
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pezter22
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My '84 had a similar issue. Although I had the key. A previous owner had disconnected the horn probably because the horn would go off if the alarm went off.

The key is a normal GM oval key. No VATS key. You can probably still get it via your GM dealer.

Corvette Central sells the door key and locks. It's probably a hassle to do it, but certainly possible.

The issue may be with the door lock and and how the alarm sets and disables. Turning the key to the right unlocks the door and disables the alarm. When I open my door the security light blinks on the DIC (Dash Information Center). That is okay.

My only repair was to fix the horn in the steering wheel. I don't know what my issue was, but that seemed to work. I just think the previous owner did not like the horn, because everything works correctly now.

I think the best thing to do is buy a copy of the FSM (Factory Service Manual) There you will find how the security system works and what to look for to repair the issue. I purchased an ebay CD version (purchase the Bishko version it's searchable)

Corvette Central link
http://www.parts123.com/corvettecent...050f&ukey=9002
Old 07-02-2015, 12:40 AM
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The 84 doesn't have vats its a simpler security system. Cliff Harris or someone will come in and help you with it. I think the first thing they'll ask is if you hear a relay click behind the drivers information center area.

When I bought my 84 it came with no door key also.The alarm went off in Michigan and with no key to disable it, I was trying everything.Everyone said disconnecting the battery cable for a minute wouldn't reset it, but it did.
Old 07-02-2015, 01:05 AM
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Hot Rod Roy
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I have an '84, also. The ignition and door keys can be made at any key shop. There's no VATS, so there's nothing unusual about the keys.

The alarm can be enabled or disabled from either door, by either pushing the power door lock buttons, or with a key in the door locks. If you want to lock the doors without enabling the alarm, slide the internal locking levers to the lock position before you close the door.

If you get a false alarm that won't reset with the key in either door, you'll first want to pull the connectors on the horns to quiet thing down. Then you'll need to disconnect the battery to reset the alarm. (I keep a 5/16 box ratchet wrench in my console for this emergency.)

Quote from the FSM: "Alarm shut down is accomplished only by unlocking either door with the key. . . . the ignition switch will not cancel the alarm once it is activated." (Pg. 8A-88)

Old 07-02-2015, 01:28 AM
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Cliff Harris
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Originally Posted by Hot Rod Roy
If you want to lock the doors without enabling the alarm, slide the internal locking levers to the lock position before you close the door.
I don't think that is true. Power door locks were an option so the only way to arm the security system on a stock car would be to use the slider (or the key, I guess). I don't think it matters how you get the door locked. As far as I know, just locking the door sets the alarm.

VATS was introduced in 1986. The older TDS system also has a starter interrupt relay behind the DIC (Driver Information Center) in the center cluster.
Old 07-02-2015, 06:59 AM
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I have an 86 so it's possible it's a little different in the door and obviously VATs vs Non-VATs. I have power locks on mine. If I use the power lock button to lock the door locks, it sets the alarm. If I use the manual lock mechanism to lock the door lock, it does not set the alarm.
If I open the door through an open window with the locks set via the power lock button using the inside door handle, the alarm goes off. If the manual lock lever was used to lock the door the alarm does not go off. If the alarm is set and I use the key to unlock the door, the alarm does not go off.
I do have the VATs system on my car, but that does not come into play yet when just opening the doors and the alarm going off or not.
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Old 07-02-2015, 07:08 AM
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Angel1000
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Originally Posted by Cliff Harris
I don't think that is true. Power door locks were an option so the only way to arm the security system on a stock car would be to use the slider (or the key, I guess). I don't think it matters how you get the door locked. As far as I know, just locking the door sets the alarm.

VATS was introduced in 1986. The older TDS system also has a starter interrupt relay behind the DIC (Driver Information Center) in the center cluster.
Wow! Woke up this morning to find all these great helpful replies to my problem and answers to my questions!
Loving this place! Thanks to ALL!
SO....
1) As I suspected, reading all about VATS and "Pellet Resisters" Etc was not needed. I should have been reading about the "TDS" security system. I will google it today.


2) Yesterday I did try disconnecting the negative battery terminal, for an hour or so, with doors unlocked. No change. IE: The words Security System (in red) appear in top of the screen to the right of the radio. Constant, not blinking, and remain on even after I leave the car (Doors locked or not, open or closed, door key locked, slider locked or electronic push button locked). This light never goes out and I assume will stay on until the battery dies.


3) The only change in this status that I "hear," is 3 short beeps when I remove the ignition key from the ignition. However, the light remains on constant.


4) I have not seen any headlamps staying on. I do see the courtesy lights in the door stay on for a few minutes after closing the doors.


5) As I mentioned at the beginning, my horn does not work and I will check today if it has been "Silenced" in some way. I did remove the horn button (at Steering wheel) and unplug and short (ground) out the wire. Horn did not sound.


6) As to door pins. To eliminate this issue, I ran jumper cable from the battery (neg) to the clean steel of the door while turning the door key back and forth. Did not disable or unarm the system.


7) I am not clear on which mode I am stuck in. IE: Disabled (error), unarmed, armed or alarm mode (An event has occurred)???
A) Steady on light means what? A breach has occurred? I should also be hearing horn and seeing lights flash?
B) Those 3 beeps I hear when removing ignition key, what is that supposed to mean tell me?


Thanks again and hope to learn more here!
I'm off to Google land... "TBS" Security systems
Angel
Old 07-02-2015, 07:20 AM
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Originally Posted by ToniJ1960
The 84 doesn't have vats its a simpler security system. Cliff Harris or someone will come in and help you with it. I think the first thing they'll ask is if you hear a relay click behind the drivers information center area.

When I bought my 84 it came with no door key also.The alarm went off in Michigan and with no key to disable it, I was trying everything.Everyone said disconnecting the battery cable for a minute wouldn't reset it, but it did.


You were right, Cliff Harris did come onboard. Awesome how you predicted that!! I did reply his comment (below).


1) Does my constant on security light status and ignition not allowing motor to turn over mean... "alarm went off?" So, now I am simply trying to shut alarm off, right? (Normally done with the door key except of course, in MY CASE!!!)


2) I tried disconnecting the battery negative for an hour or so. Left door unlocked also. Reconnected battery. Security light came back on and engine wont turn over. IE: Nothing changed.


Nice to meet you Toni
Angel
Old 07-02-2015, 07:34 AM
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Angel1000
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Originally Posted by antfarmer2
Found this for you


The #1 problem is typically the lock switches
#2 the door pins not grounding correctly
#3 The logic circut that leaves the lights on for a min or 2 on exit of the car ( does this work?)
#4 BAD horn relay


Thanks for your thoughts and help!


1) Odd that both sides would simultaneously go bad, right? Humm?


2) Heard about this possibility so, I ran a jumper cable from battery ground to clean steel on the door and also to the key itself. Turned to lock/unlock a few times. Did not turn alarm off.


3) I will check this today. I haven't even figured out how the lights work yet. Is there some auto function here? Auto off? So far, I just saw a pull switch upper left from steering wheel. When I pull it, the lights flip up and turn on.. Well, the right one doesn't always flip. (Another thread, another day!!)


4) Horn Relay. Very Interested in this issue. I just noticed yesterday, the horn not working. Previous owner said horn always worked. I Took apart the button at steering wheel and jumped the only wire to ground. No horn sound.
I will be looking further into this today.


Thanks again!
Angel
Old 07-02-2015, 08:09 AM
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357L98
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I have an 85 and I think the security system is the same as an 84. The system could only be armed by pressing the power lock button on either door. It could only be disarmed by unlocking the door from outside using the key. One day, the horn started blowing all by itself and the car would not start. Security light flashing. I found that the security module under the passenger side dash had malfunctioned. I unplugged it, and the car started fine. There is a starter disable relay behind the DIC in the center dash. Just to make sure I had no future problems, I removed this relay and crimped the starter wires together.
Old 07-02-2015, 08:29 AM
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Angel1000
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Originally Posted by hcbph
I have an 86 so it's possible it's a little different in the door and obviously VATs vs Non-VATs. I have power locks on mine. If I use the power lock button to lock the door locks, it sets the alarm. If I use the manual lock mechanism to lock the door lock, it does not set the alarm.
If I open the door through an open window with the locks set via the power lock button using the inside door handle, the alarm goes off. If the manual lock lever was used to lock the door the alarm does not go off. If the alarm is set and I use the key to unlock the door, the alarm does not go off.
I do have the VATs system on my car, but that does not come into play yet when just opening the doors and the alarm going off or not.


Thanks so much!
What I am understanding from your narrative is that the difference between TBS (my system) and the VATs (86 and newer system) does not come into play until the ignition key (pellet) is involved. Other functions are the same. I too, have power locks. So setting alarm, unsetting alarm, etc should work the same.


I have tried so many things that I am confused as to whether or not I actually did things in the order you described. I will verify today. IE: Window(s) open, doors locked via manual slide button, ignition key out. I assume there is some wait time associated?? I will wait 2 hours. Then, reach in the window, slide the door lock to unlock manually, open door via inside handle, get in the car, insert ignition key and turn to start.
Hope this works, but I do "believe" I have done this at least once and still, security light stays on and engine wont turn over. In fact, after two hours, I approach the car, look through the window and see the security light still on. Isn't it supposed to time out and turn off?
Thanks again,
Angel
Old 07-02-2015, 09:01 AM
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Originally Posted by 357L98
I have an 85 and I think the security system is the same as an 84. The system could only be armed by pressing the power lock button on either door. It could only be disarmed by unlocking the door from outside using the key. One day, the horn started blowing all by itself and the car would not start. Security light flashing. I found that the security module under the passenger side dash had malfunctioned. I unplugged it, and the car started fine. There is a starter disable relay behind the DIC in the center dash. Just to make sure I had no future problems, I removed this relay and crimped the starter wires together.

Thank you for replying!

I like your thinking. Besides, do people still steal these cars?? After all, an 84 isn't exactly one of those "Money Year" cars! Don't car thieves today just do home invasions, rape you, kill you, start your house on fire and then just take your car keys and drive away?? So sad!


If all else fails or if I need to move the car before I figure out the root problem, I plan to follow your course of actions. To this end..
1) Unplug security module: If I lay on passenger floor and look up under the dash with a flashlight, what am I looking for? I assume some small black plastic box with 5/10 or so wires connected to it? Will it be obvious or hidden behind some carpet or wiring harness?
I doubt there will be a big yellow sticker saying "Before stealing this car, unplug this module"


2) Starter Relay: I saw a utube about this. I think there were some fuses hidden behind there and more than one module. The left most module I believe was a horn module, to it's right was the starter module and I think there was some other electronic device to the right of that module?? They were showing how to jump out the starter module. They Unplugged the connector and jumped first pin to last pin (That sound much like what you did by "crimping the starter wires together"). This did not solve the horn sounding issue, but this guy could than at least drive his car home.


Thanks again,
Angel
Old 07-02-2015, 09:08 AM
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Angel1000
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Originally Posted by Angel1000
Wow! Woke up this morning to find all these great helpful replies to my problem and answers to my questions!
Loving this place! Thanks to ALL!
SO....
1) As I suspected, reading all about VATS and "Pellet Resisters" Etc was not needed. I should have been reading about the "TDS" security system. I will google it today.


2) Yesterday I did try disconnecting the negative battery terminal, for an hour or so, with doors unlocked. No change. IE: The words Security System (in red) appear in top of the screen to the right of the radio. Constant, not blinking, and remain on even after I leave the car (Doors locked or not, open or closed, door key locked, slider locked or electronic push button locked). This light never goes out and I assume will stay on until the battery dies.


3) The only change in this status that I "hear," is 3 short beeps when I remove the ignition key from the ignition. However, the light remains on constant.


4) I have not seen any headlamps staying on. I do see the courtesy lights in the door stay on for a few minutes after closing the doors.


5) As I mentioned at the beginning, my horn does not work and I will check today if it has been "Silenced" in some way. I did remove the horn button (at Steering wheel) and unplug and short (ground) out the wire. Horn did not sound.


6) As to door pins. To eliminate this issue, I ran jumper cable from the battery (neg) to the clean steel of the door while turning the door key back and forth. Did not disable or unarm the system.


7) I am not clear on which mode I am stuck in. IE: Disabled (error), unarmed, armed or alarm mode (An event has occurred)???
A) Steady on light means what? A breach has occurred? I should also be hearing horn and seeing lights flash?
B) Those 3 beeps I hear when removing ignition key, what is that supposed to mean tell me?


Thanks again and hope to learn more here!
I'm off to Google land... "TBS" Security systems
Angel

PS: I got No results from my Google search "1984 Corvette TBS security System"

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Old 07-02-2015, 10:23 AM
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Hooked on Vettes
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You mention you hear 3 short beeps after removing the ignition key.
Some after market radios do that.

Are you sure there is no after market alarm?

Read this thread.

http://www.corvetteactioncenter.com/...ml#post1167592
Old 07-02-2015, 11:38 AM
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ToniJ1960
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I was looking for a page I found before on the system for 84,and so far cant find it I thought sure I saved it.

Anyway I found this and cut it out maybe something in it will get you started on the right rack, while I keep looking.
'84 Alarm SYS 101
Alarm: As described by Patrick above.

Protective Switches:
Doors/Door Lock Anti-Tamper Switches (CKT 263, LT BLU)
Hatch (CKT 260, DK GRN)

Fusing:
The ELE Theft Deterrent Control Module is 10 amp fused (located at lock pillar support - e.g., PASS side kick panel).
The IGN Switch Disarm signal is provided through the radio fuse.
The Security Warning Indicator is provided through the CTSY CLK fuse.

Controller:
All electronic, 2 stage (Armed & Activated).

Starter Interrupt Relay:
Normally closed in starter solenoid circuit. When energized, relay contacts opens to disable starter solenoid curcuit (6). (Located near the controller & plugged into controller harness.)

Troubleshooting: Check:
Fuses
Control Module GND (I/P GND, PASS, A Pillar).
BAT feed CKT 940 (ORN/BLK).
Power door lock circuits.
Lose Connectors.
Control Module.
Horn.

Alarm activates by itself:
On manual lock SYS, CKT 295 (GRY) is OPEN at Control Module.
Check for too close adjustment of door jamb switches.
Faulty Door Lock Anti-Tamper Switches (my addition, based on personal experience & not in CSM).

[CSM, 1984, 8A-85-92.]
Old 07-02-2015, 02:49 PM
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Angel1000
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Originally Posted by ToniJ1960
I was looking for a page I found before on the system for 84,and so far cant find it I thought sure I saved it.

Anyway I found this and cut it out maybe something in it will get you started on the right rack, while I keep looking.
'84 Alarm SYS 101
Alarm: As described by Patrick above.

Protective Switches:
Doors/Door Lock Anti-Tamper Switches (CKT 263, LT BLU)
Hatch (CKT 260, DK GRN)

Fusing:
The ELE Theft Deterrent Control Module is 10 amp fused (located at lock pillar support - e.g., PASS side kick panel).
The IGN Switch Disarm signal is provided through the radio fuse.
The Security Warning Indicator is provided through the CTSY CLK fuse.

Controller:
All electronic, 2 stage (Armed & Activated).

Starter Interrupt Relay:
Normally closed in starter solenoid circuit. When energized, relay contacts opens to disable starter solenoid curcuit (6). (Located near the controller & plugged into controller harness.)

Troubleshooting: Check:
Fuses
Control Module GND (I/P GND, PASS, A Pillar).
BAT feed CKT 940 (ORN/BLK).
Power door lock circuits.
Lose Connectors.
Control Module.
Horn.

Alarm activates by itself:
On manual lock SYS, CKT 295 (GRY) is OPEN at Control Module.
Check for too close adjustment of door jamb switches.
Faulty Door Lock Anti-Tamper Switches (my addition, based on personal experience & not in CSM).

[CSM, 1984, 8A-85-92.]


Hello again and thank you!
Im at car now. Got dash ripped apart. Was able to start car. But, this happens via BACK DOOR trickery. IE: Jumped out the starter relay wires. Car started and ran.
So, seems the security system is stuck in the activated mode. I found the horns disconnected, at the horns. The horn relay was very hot, which is what I think is drawing my brand new battery down every night!
When I plugged horn wires back in, horn blasts constantly. I unplugged the "very hot" horn relay and the horn stops blasting. However, this also makes normal horn operation fail.


I guess I could stop here and use the car with no horn. IE: Remove horn relay (Relay works correctly, but it is getting constant signal from security center to blast (Green wire)), disconnect starter interrupt relay and jump the starter wires (Purple) so car will start.


I'm not like that though!!! Got to look further! TRY TO FIX!!
QUESTION!! Why is security center sending signal to sound horn and interrupt start function??? And, why can't I turn it off (Door Key signal)???
In search of security center I found a huge mouse nest behind the passenger crash pad. Thought I found the cause of the problem, but after clearing the Air freshener/mouse nest, I see no visible damage caused by my little hitch hiker.
Getting close to security center now... I am following the thick green wire from starter interrupt relay. I assume it gets signal/voltage from security control center. Seems it is located somewhere near the car's main computer which is mounted behind pass crash cushion. Need 3 elbows!!! Good thing I have skinny arms! LOL
Side thoughts: What are the only things that tell security to activate.
1) Tamper switch in doors? Assuming this car has them?
2) Door was opened while alarm in armed mode. But why can't I turn this alarm off?? Back to door key switches, which seems odd that both sides would fail at same time.
3) Does the hatch window have a alarm trigger?
4) What triggers the alarm in the first place? The door light button? A separate push button on the door jamb, triggers the alarm?


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