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Cadillac Repair/90 caddy fleetwood Cpu


QUESTION: My baby is my car and it needs a new cpu where is it located on my car and how do I do the replace and reinstall my dad left me with homework I can't seem to find on Google I'm a novice and my dad has 20 plus years and will be helping when I get to the replace and reinstall ... again the Cpu that talks to the Transition thanks

ANSWER: Not sure what you are calling a CPU. This vehicle has either an ECM (Electronic Control Module) or a BCM (Body Control Module) located in the right kick panel or under the passenger side of the dash.
How did you determine what the car needs? This is the old OBD1 system that was replaced with OBD II. A standard still being used today.
The problem with the old system like in that vehicle is people try to diagnose the problem with the diagnostic flashes in the dash. Unlike the OBD II which will pin point the problem, the old system will tell you the circuit failure, but not the exact component. It was a horrible system to work with even as a seasoned GM Tech.

Tell m the whole story that leads you to believe that you need a computer and maybe I can help.


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QUESTION: The car was passed down second hand it's climit and fuel century used to alternative flashing and now they have turned off completely the fuses were just done and my caddy doesn't like going in to passing gear with out loosing all its GO! WE CANT OUT RUN TRACTOR! then at other times it is fine my mom's mechanic did a diagnostic said it is not the transition but the computer that's so post relay the information to the auto tranny so I need to know where this computer is located so it can be replaced


As I had stated, it's located either in the passenger kick panel inside the vehicle or under the passenger side of the dash. You won't miss it. Will have 2 to 3 harnesses running to it with about 50 wires.


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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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