When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Theft Deterrent Relay (behind info center) missing altogether. What color wires should i be looking for that are crimped together, and what about the control side of relay wires. I cannot see any wires where the TDS relay is supposed to be.
The Theft Deterrent Module is still installed behind the breadbox, still plugged in.
The single fuse located behind the info center, beside the hazard flasher, was unplugged.
Does this sound like the Theft Deterrent System in this 84 has been disconnected so it has no effect on anything at all?
Im suspicious it is still somehow working to blare the horn and interrupt the starter as my horn is currently blasting (no beeps) and neither will the car crank. Furthermore the prior owner has ripped into the horn on the steering wheel its guts are all missing.
So….thats why im suspicious of the tds somehow still interupting the starter and causing horn to blast.
Maybe this will help👍 Bonus Pic Bonus Pic Bonus Pic 📸 Manual Transmission Hatch Release Bonus Pic Automatic Transmission Hatch Release Bonus Pic Bonus Pic Bonus Pic Bonus Pic Final Bonus Pic👍
Edit: click on pics for better resolution
1000x Thankyous!!!!!!!!!!!!!!!!!
Im waiting for my 84 manual to arrive.
A bubba who owned this car had a bose amp replay in place of the theft detterent relay. It may have been working because he jammed a piece of wire in to ensure the relay was always closed allowing power through.
Your pics will allow me to troubleshoot the system to ight thank you!!
inside the relay..what i found
and the cover for the true theft detterent relay was in the center console.
this is the actual relay required. i will temporarily jump the purple and the dk gree/wt to ensure the starter cannot be interrupted by the module. thanks!!!!
A bubba who owned this car had a bose amp replay in place of the theft detterent relay. It may have been working because he jammed a piece of wire in to ensure the relay was always closed allowing power through.
Your pics will allow me to troubleshoot the system to ight thank you!!
inside the relay..what i found
and the cover for the true theft detterent relay was in the center console.
this is the actual relay required. i will temporarily jump the purple and the dk gree/wt to ensure the starter cannot be interrupted by the module. thanks!!!!
No problem! These were all taken from "Electrical troubleshooting shop manual supplement". I have other '84 specific GM manuals, just let me know if you need pics of anything else!!!! Good luck👍
Edit: been following your thread on the '84 of your daughter's, very cool on so many levels!!!!!
That GM# 1616422 I believe was only used for '84 & '85 model years in the C4. Many early GM of other branding though '80 - '87 - A correct would be only that #.
***** There does seem to be maybe a couple after-market equivalents You'd need to confirm but BWD - R6000 or SMP - RY-49.
That GM# 1616422 I believe was only used for '84 & '85 model years in the C4. Many early GM of other branding though '80 - '87 - A correct would be only that #.
No problem! These were all taken from "Electrical troubleshooting shop manual supplement". I have other '84 specific GM manuals, just let me know if you need pics of anything else!!!! Good luck👍
Edit: been following your thread on the '84 of your daughter's, very cool on so many levels!!!!!
Thank You for showing us the manuals the images are from. And thanks for following along on Victorias 84 thread 👍
There is something special about C4’s that attracted the worst offending bubba owners in the deepest depths of their depreciation curve that they are just emerging from now. Layers and Layers of issues. Band aid fixes.
Im sure c3’s went through a similar phase but there are so many more electrical places that can be messed with on the c4.
interesting 84 tds theft deterrent system operation
so if the tds conroller isnt satisfied in an 84, it energizes the coil of the starter interrupt relay, and now power to the starter solenoid is….interrupted. ie, turn key, no crankage.
if the electric door locks are used to lock the door before you leave, then when then once both doors are closed, the “arming” process begins and within 5 seconds—its armed. Pretty cool that GM built in an alarm.
There are two ways to disarm the system. Assuming you are not inside the car…then as u approach the car, u must use the key to open the door lock. You cannot reach in the window to slide the door lock. Well….you can. But you will set the alarm off when you open the door!
Unless! you also use the second method of disarming the alarm….which is to insert the ignition key to ON. U dont have to start the car. Just turn it to ON. This was confusing to me….why would you ever have the alarm set with you inside already? And ofcourse, it does make sense.
Lets say Victoria pulls up to drop a friend off at her house, and they decide to stay in the car and have girl-talk out front of the house first. Victoria shuts the car off, then locks the doors using the power door lock button just to keep any strangers from opening the door on her while they are inside. Good move Victoria.
Except that you also armed the alarm! Now you could roll down the window and try to finagle the door lock key into the door lock and to disable the alarm..except no, in order to do that she would have had to put the ignition key to ON to power the window so the alarm was already disabled.
But this is interesting. IF THE alarm trips, and starts honking at you, there is only ONE way to shut it down, that is by using the door key to turn the door lock to the unlocked position.
I know we have all done it. pull up to destination with windows down, get out of car and tap the power door lock to lock the doors. even though we left the window down. then walk up with bag of whatever in hand…reach in door..feel for the slider…unlock…open door…and alarm goes off and beeps horn until we insert door key and position key cylinder to unlock position even though door is already unlocked from the slider.
now….if you reached in the window and inserted the ignition key and turned it to the ON position prior to opening the door you unlocked with the slider…you would have been fine.
ha!
Thnx for the help. And Note, I think there may be a small difference in the 85’s system…maybe not.
Later in 86 when VATS was introduced as a seperate stand alone ststem, TDS was left in place, but the ability to kill power to the starter via the interupt relay circut was removed and it simply operates the horn. VATS took over the starter and maybe even the fuel. not sure exactly. This lost is not about VATS but i feel i need to me tion it so future readers realize that TDS is seperate and distinct from VATS.
there are other posts about this but there was some info ommitted. which makes me think about one more thing. Years ago Cliff Harris pondered what if you only have manual door locks on your 84/85. Can the system still be armed if with power door locks we use the power lock button to lock? Answer, yes, you slide BOTH door locks to locked position, and it is set.
Later in 86 when VATS was introduced as a seperate stand alone ststem, TDS was left in place, but the ability to kill power to the starter via the interupt relay circut was removed and it simply operates the horn. VATS took over the starter and maybe even the fuel. not sure exactly. This lost is not about VATS but i feel i need to me tion it so future readers realize that TDS is seperate and distinct from VATS.
One tiny correction on the relay. The VATS still used the UTDS Relay, but the output was wired kinda backwards to the NO (Normally Open) contacts instead of the NC (Normally Closed) contacts as it is in the ‘84-‘85. Wiring this way makes it a Start Enable Relay for VATS instead of a Start Inhibit Relay on ‘84-‘85. The connection from the UTDS Module is not used to energize this relay in ‘86-‘89, instead it is energized by the VATS Module. When VATS recognizes the correct key resistance, it energizes the relay, closing the NO contacts and completes the circuit to the starter solenoid instead of the UTDS activating the alarm and energizing the relay, breaking the NC contacts and opening the circuit to the starter solenoid as in the ‘84-‘85. Same relay, same location, just wired to function differently. The VATS Module also does a fuel enable to the ECM when recognizing the correct key resistance, but that side of the system is beyond the scope of the relay difference between ‘84-‘85 and ‘86-‘89.
Last edited by Ray Quayle; Feb 2, 2023 at 02:29 PM.
1984 Theft Deterrent System technical help.
