99 buick century pcm bcm ignition staring diagram wiring

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where is the fuse for a buick century 99
Doesn't turn on the whole board

Buick Century (1997-2005) fuses and relays

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Fuse box diagram (location and assignment of electrical fuses and relays) for Buick Century (1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005).

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The back up lamps are computer controlled (BCM) . Very doubt full you will be able to fix . You have a factory or professional type scan tool ? Has bi- directional controls ( do you know what this is ?) The transmission internal mode switch is an input to the PCM - engine computer or TCM - transmission control module .The PCM or TCM,when it see's the transmission is put into reverse sends a serial data message to the BCM which turns on the back up lights . But here you go ,free wiring diagrams here http://www.bbbind.com/free-tsb Enter vehicle info. year , make , model an engine size . Under system click on lighting ,under subsystem click on reverse lamps . Click the search button then the blue link . This for the lamp side of the circuit ,from the BCM . To see internal mode switch input to pcm you need look under transmission / transaxle .

Having the vehicle checked for codes should have been the first thing done . Security light on ,a code is stored in the control module that controls the anti-theft system ! This is if you want it fixed right !
Important: If the wrong ignition key is used in an attempt to start the vehicle, a Data Trouble Code (DTC) will be set and the Body Control Module (BCM) will not send a fuel enable or starter enable message to the Powertrain Control Module (PCM) for three minutes even if the correct ignition is used.
The Pass-Key II® Theft Deterrent system prevents vehicle theft by disabling the starter motor and fuel system. If the Body Control Module (BCM) dose not identify the use of the correct ignition key to start the vehicle, the (BCM) will communicate a message to the Powertrain Control Module (PCM) which will disable the crank relay and fuel delivery to the engine.
When the (BCM) identifies the use of the correct ignition key (resistor pellet) to start the vehicle, the (BCM) will send a fuel enable and starter enable message to the (PCM) which will allow the vehicle to start.

DTC B2957 Security System Sensor Data Circuit Low
DTC B2958 Security System Sensor Data Circuit High
DTC B2960 Sec Sys Sensor Data Incorrect but Valid
DTC B3031 Security System Controller in Learn Mode
DTC B3094 No Response from ECM/PCM Received

or you can do a by pass that may or may not work ! You could measure the resistance of the pellet on the side of the key , then go to radio shack a by a resistor of the same value ! Then find the wires under the dash that come from the ignition switch ! Solder the resistor into the harness side wires , not going back to ignition switch . The wires break or contacts inside ignition switch do . You could check resistance with ohm meter . Put key into the ignition switch , find those wires i said about before . Check resistance at the wires under dash , is it the same resistance as pellet ?

Make sure battery has a full charge and battery connections all good. Check fusible links where applicable. Any component that doesn't work and is fuse protected, not only check the fuse, check the fuse circuit for voltage, use a test lite.
The wiring diagram is for starter circuit, you can see the fuses. Any testing for starter motor, make sure tranny is in park or neutral and parking brake is set. It is possible to jump crank relay to see if starter motor will crank, but, that doesn't mean it will start. Make sure vehicle can't move.

It's the anti-theft system . (SECURITY ) Keeps vehicle from being stolen !
Important: If the wrong ignition key is used in an attempt to start the vehicle, a Data Trouble Code (DTC) will be set and the Body Control Module (BCM) will not send a fuel enable or starter enable message to the Powertrain Control Module (PCM) for three minutes even if the correct ignition is used.
The Pass-Key II?® Theft Deterrent system prevents vehicle theft by disabling the starter motor and fuel system. If the Body Control Module (BCM) dose not identify the use of the correct ignition key to start the vehicle, the (BCM) will communicate a message to the Powertrain Control Module (PCM) which will disable the crank relay and fuel delivery to the engine.
When the (BCM) identifies the use of the correct ignition key (resistor pellet) to start the vehicle, the (BCM) will send a fuel enable and starter enable message to the (PCM) which will allow the vehicle to start.
Your best bet would be have it towed to a qualified repair shop !

With out a key how are you going to unlock steering ?
The steering column lock !
Beside that you would have to get around anti-theft system ! An the fact that all functions on your vehicle are controlled by computers ! The ignition is an input to the BCM - body control module !
Serial Data Power Mode
On vehicles that have several control modules connected by serial data circuits, one module is the power mode master (PMM). On this vehicle the PMM is the Body Control Module (BCM). The BCM receives 4 signals/circuits from the ignition switch. These are the Ignition 0, Ignition 1, Crank and Accessory 1 ignition switch signals/circuits.
To determine the correct power mode the BCM uses:
• The state of these signals/circuits, either switch closed (B+ = 1) or switch open (open = 0)
• The sequence of switch closures received by the BCM
• The status of the engine run flag.
I'd say you don't have a snow balls chance in guam of hot wiring this vehicle ! There made so that can't be do ! So have it towed to a GM dealer or some other qualified repair shop ! Because if you start jumping wires you'll burnt of computers etc....

How do you know it needs to be replaced ? This is a very complex starting system , the ignition switch is an input to the BCM . The BCM is hooked to the GMLAN serial data communication network .The BCM tells the PCM start has been requested , The PCM then activates high side drivers sending power through the automatic transmission mode switch to ground , If in park or neutral . Then the PCM will energize the starter relay .

No you can't ,the resistance is in the pellet , not transponder , that's newer pass-key 3 .
When the (BCM) identifies the use of the correct ignition key (resistor pellet) to start the vehicle, the (BCM) will send a fuel enable and starter enable message to the (PCM) which will allow the vehicle to start.
You need the key to measure the resistance !

pcm is the computer for the engine
bcm is the computer for the body accesories

change bulb in front if indicator doesnt blink or blinks fast if new bulb check socket connectors may have corrosion or damaged wiring