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Cadillac Repair/98 cadillac seville sls


QUESTION: Hi Just bought a security system with a bypass module (omega)and i was wondering where are the wires i need to connect it(trunk release, door locks, accessories,etc). and if your willing can you guide me in, im a novice trying not to break nothing sorry.

ANSWER: Hello Anthony,

To be perfectly honest, what you are requesting may be over the head of a novice. First, you did not give the year, make, model as to what the system is being installed in. Door locks can be tricky depending on the vehicle. Everything is tapped into under the dash. Most of these functions is dependent on relays including not limited to the trunk release,door locks, starter disable, remote start if equipped and in that case many times the factory theft deterrent needs to be bypassed. The tach wire has to be tapped into under the hood and it all depends on the vehicle as to how the factory theft deterrent is bypassed.

Installation cost by a professional is not all that expensive compared to what you are going to embark in. This as I said is NOT a job for a novice. I am a seasoned professional and I had issues even with detailed schematics causing me to contact the alarm manufacturer's tech line.

You can find instructions on the internet by searching for the name brand of security and possibly for your exact year make and model. Other instructions have to be considered with a jaundice eye questioning the motivation of the person giving the instructions. What is in it for him? Is he leaving out information intentionally where you are forced to pay him to get the engine running again? Don't mind me, after the life experience I have in vehicles and even the court system as an expert, I am very cynical.

If you can go back to where you purchased this alarm (hopefully not from places like Crutchfield, where there is no way to get it installed)see if you can pay the money to get it installed. If you bought from a place such as Crutchfield, you may want o call around to local alarm stores and ask them as to their price to install it. Please understand my reference to Crutchfield is not derogatory. The problem is in many cases, they sell all sorts of electronics, but they offer no installation.

Look, if it was an easy install, I would be more than glad to help you, however there are too many factors involved dealing with vehicle computer systems tha could turn into an issue.

Good luck and let m know the final result.

---------- FOLLOW-UP ----------

QUESTION: Hi i have a 98 cadillac seville sls and im wondering where is the ignition harness located


Please read this answer further to assist your installation of your alarm as well.

The ignition harness is two tiny wires that attach to the ignition lock cylinder. The ignition lock would have to be replaced with the harness. The dealer charges $800.00 to replace this junk.

The VATS causes intermittent no start conditions. The wires break inside the plastic insulation. You will never see the break and moving the wiring like tilting the column puts them together and the engine starts.

The cheapest easiest way to approach this problem is to bypass the system. Any alarm store can bypass for about $60.00 and you will never have a starting problem again.

Now, on the ignition start wire itself for the alarm starter disable, you can check with test light by probing into the wire. You pull down the hush panel attached with either 10mm head bolts at the fire wall or wing nuts because the used both. You then use a 9/32 or a 7 mm socket and remove the screws attaching the hush panel to the dash. You can now look at the bottom of the steering column and all the wiring.
Do not probe the yellow air bag wire. There are warnings on that wire. You will see two harnesses under the steering column. One of those yellow wires you will probe will only be hot when key is in start position past the on. That is your starter disable wire. Cut and attach to two ignition interrupt wires from module.

Now, I believe you were speaking remote start as well and all I can tell you is follow the instructions, however the VATS has to be bypassed anyway as described for the engine to start without a key in the ignition from a distance.

You will also catch your locks by the kick panel on the driver's side, but sometimes locks are difficult because on some cars one relay is used for lock and the other is for unlock.

I do not remember if your trunk release is in the driver's door or not. If so, you catch that wire under the dash as well.  

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Rob Painter


Alarm system questions cannot be answered on this forum. These systems are not what I can answer. Without being physically at the vehicle and not knowing what kind of electrical service has been done on the vehicle, there is no possible way to give an accurate answer over the internet. My expertise is in Ignition/key based anti-theft systems. These issues include GM VATS (resistor chip in key blade) PASSLOCK (MRD)-ignition lock rotation based, no special ignition key and the PKIII Transponder (computer chip in key) systems. These systems are not alarm based and are integral with the starting of the engine. This is why I cannot diagnose alarm problems without physically looking at the vehicle: Alarm systems are a completely different annimal than ignition key/lock based anti-theft system. Many alarm questions come from vehicles 10 years old, and since older, many hands that had been involved over the years.I am an expert in all GM factory (ignition/key based)systems. Alarm system questions pose to many situations beyond my knowledge as to what has been done to the vehicle over the years. Some guy may have actually wired the stereo into the alarm system. Who knows? Over my past 30 years in vehicle wiring repair, I have seen unbelievable wiring disaters done by guys that consider themselves "mechanics." I have seen stereos and alarms intalled using surgical tape. I have seen modules burn up, un-fused circuits, wiring jambed between the doors and even lamp cord used for a starter kill. To answer alarm questions over the internet without examining the vehicle is like asking; What does it take to remove a dent?


Education/Credentials-ASE certified. 11 years with a GM dealer and 17 years with a repair facility dealing with only the repair of theft recovered vehicles.

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