Top 20 1999 Cadillac DeVille Questions & Answers

It may be more than just your key. You may have an issue at the Theft Deterrent Module. This is something that can be bypassed, but it is a tough install. http://www.diy-gm-security.com/

https://postimg.org/image/dk95bciad/ Hope this helps?

air lock in the system have it professionally bled out at a radiator shop

bad temp sensor or wiring harness issue.

What you may be hearing is hum from a low voltage power module under the dash, which is activated every time you open a door. It should shut off after doors are closed, all timed devices (such as cabin lights) turn off and the key is not in the ignition. If your battery is in good condition, then either this module, the keep-alive module or something else drawing current is not shutting off the way it is supposed to. Start by checking for trouble codes (DTCs) with a good code reader.

Heater core sounds to be leaking but check all the hoses going to heater, could be loose and leaking into the vehicle. I’m happy to help further over the phone at https://www.6ya.com/expert/pat_7f6b46a4565f904d

see if you can find it at this link. Where is the fuse for the horn on 1999 cadillac deauville Google Search

Engine Cooling Fan Relay 1 In the center front of the engine compartment, on the lower radiator support, near the cooling fans Engine Cooling Fan Relay 2 In the center front of the engine compartment, on the lower radiator support, near the cooling fans Engine Cooling Fan Relay 3 In the center front of the engine compartment, on the lower radiator support, near the cooling fans

If your key has the resistor pellet with the short wires on both sides of the shank, I can provide a bypass method. Basically, you make a small resistor of ohms equal to the key, cut the passlock wires at the bcm, and solder the resistor to the bcm side of the wires. I have done this many times.

The bad news is that it is most likely a faulty actuator and this will be difficult to replace as they have to partially dismantle the dash to get at it. Go to a couple of dealers and get them to give you a quote for the work. They may not be able to give you an exact quote as they wont know exactly what the problem is until it is dismantled, so ask for an estimate. Jobs like this usually wont be expensive for parts, but there is a lot of labour involved..

Have the dealership call GM and get a Cadillac professional to their dealership..they CAN do it... ( I am a former GM Supplier Quality Engineer )

Computer glitch , have it checked for DTC'S - diagnostic trouble codes . Not all codes turn on the check engine light . Plus DTC'S for the BCM - body control module won't turn the check engine light on at all , could turn on a yellow wrench symbol on the insturment cluster . Stop putting head gasket sealer into the cooling system , could clog it up.

Diagnostic Aids • It is very important that a thorough inspection of the wiring and connectors be performed. Failure to carefully and fully inspect wiring and connectors may result in misdiagnosis, causing part replacement with reappearance of the malfunction. • An intermittent malfunction can be caused by poor connections, broken insulation, or a wire that is broken inside the insulation. • If an intermittent malfunction exists, refer to Intermittents and Poor Connections Diagnosis in Wiring Systems. Do you know how to do automotive electrical wiring trouble shooting ? Use a DVOM - digital volt ohm meter ? How to use a wiring diagram to pin point testing spots in a electrical circuit ? Testing before replacing parts is key !

You may have an air lock in the system. This is a pain with these engines, and Cadillac has a specific procedure for removing them (see Alldatadiy.com). Otherwise, your water pump may be shot, or there is a blockage somewhere in the cooling system (are you absolutely sure the thermostat is working - installed the right way?). Also, are both the radiator fans running when it starts to overheat? If not, may have a blown fuse, or the relay for the fans may be shot. All car manufacturers strongly recommend using an all-type antifreeze because it also contains corrosion inhibitors - tap water alone is not a good idea. Most good battery chargers will trickle charge a charged battery - this is normal. Even with the car shut off, there will be a small drain on the battery to keep the electronics alive. HOWEVER, for this same reason, it is never a good idea to use a battery charger while the battery is in the car, or to jump start a dead battery in the car - the electronics do not like this.

Logically, if there is power at the solenoid all the time there is a problem with the brake switch assembly or wiring. If not, the solenoid may simply be stuck in the activated position.

Could be that the hvac control module has an intermittent problem or the air mix door control for the passenger side is sticking. Check for error codes (DTCs) using a code scanner, but may not show an intermittent mechanical issue. If you can get at the air mix control on the hvac box under the dash on the passenger side, you may be able to check its operation.

could be a air pockets in the coolant system that have top bled out it is a simple exercise to have a compression test done to check for head gasket or cracked head

The Trainer 24 Power Window Troubleshooting Test the electrical circuit ! Could be the window regulator ! Or check the wiring inside the rubber boot that comes from the body to the door . Over time these wire can break .

need to check the wiring and connections for corrosion or damage

Unless these starters are rebuilt by AC Delco, Bosch, or other major player rebuilders they are likely very poor quality rebuilds. It sounds like the problem you have may be the starter solenoid contacts are burnt. When they rebuild the starter at the cheap shops they only replace what is showing up as defective, so not all worn parts are replaced. As a professional tech for over 35 years and a ASE Master technician I only use OEM rebuilds, never Autozone or other so called discount auto parts stores rebuilds. If you want to order from a site that has quality rebuilds at cheap rebuild prices go to the website at the link below.. I have seen people who bought 4 starters to get one good one, same goes for Alternators RockAuto Parts Catalog