Could loss of communication with (bcm) be a reason that it will not register in park. the battery had died one night while cleaning the car with all doors open. the next morning when no start no crank
Sometimes when i pull up and go to get out the key will not come out and i have pull the shi8fter as if tring to reverse and then let it go to make it go all the way in park. my traction control light,abs,check engine loights are all on. the security light is coming on and going off like normal i suppose.
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Will not spin over ? When you turn the key to start ,the starter doesn't engage an spin the engine ? Dash light's come , headlamps come on bright ? Battery good , charged ? No codes ? just engine ,OBD 2 codes ? BCM codes ? How or what did you use to check codes ? code reader , scan tool ? A professional type that can read BCM - body control module codes ? Do you have any idea how complex the electronic's are on this vehicle ? Do you know what happen's when you turn the key to start ?
Power Mode Master
This vehicle body control module (BCM) functions as the power mode master (PMM). The ignition switch is a low current switch with multiple discrete ignition switch signals to the PMM for determination the power mode that will be sent over the serial data circuits to the other modules that need this information, and so the PMM will activate relays and other direct outputs of the PMM as needed. Refer to Power Mode Description and Operation for a complete description of power mode functions.
The body control system consists of the body control module (BCM), communications, and various input and outputs. Some inputs, outputs and messages require other modules to interact with the BCM. The BCM also has discrete input and output terminals to control the vehicle's body functions. Battery positive voltage is provided to the BCM from the BCM fuse in the underhood fuse block. The module has two grounds at G 202 as well as one directly to the vehicle battery. The BCM is wired to the GMLAN High speed serial data buss and the GMLAN Low speed serial data buss and acts as a gateway between them. If the BCM does not communicate the vehicle will not start due to the inability of the engine/powertrain control module (ECM/PCM) and vehicle theft deterrent (VTD) control module to communicate without the BCM providing the gateway function.
The body control module (BCM) in this vehicle functions as a gateway or translator. The purpose of the gateway is to translate serial data messages between the GMLAN high speed buss and the GMLAN low speed buss for communication between the various modules. The gateway will interact with each network according to that network's transmission protocol.
One example of this necessary communication is the communication between the engine/powertrain control module (ECM/PCM) which is high speed serial data and vehicle theft deterrent (VTD) control module which is low speed serial data. If these modules can not exchange information, the vehicle will not start.
All communication between the BCM and a scan tool is on the High speed GMLAN serial data circuits. A lost communication DTC typically is set in modules other than the module with a communication failure.
If you don't know of any of this ,your best bet , take it to a qualified repair shop.
Where have you been looking ? RPM signal for what ?
The IPC displays the engine speed as determined by the BCM via a class 2 message. The BCM receives a class 2 message from the PCM indicating the engine speed. The tachometer will default to 0 RPM if:
• The PCM detects a malfunction in the engine speed sensor circuit.
• The IPC detects a loss of class 2 communications with the BCM.
• The BCM detects a loss of class 2 communications with the PCM.
The CKP sensor is used for ignition timing, the fuel injector timing, misfire diagnostics and tachometer display. The CKP sensor is connected to the ECM by a signal circuit and a low reference circuit.
The electronics involved are unique to say the least .
The instrument panel cluster (IPC) displays the vehicle speed based on the information from the body control module (BCM). The engine control module (ECM) calculates the vehicle speed based on the controlled area network (CAN) serial data message indicating the wheel reference speed from the electronic brake control module (EBCM). The ECM sends a CAN serial data message to the BCM indicating the vehicle speed. The BCM sends a class 2 message to the IPC indicating the vehicle speed.
The speedometer defaults to 0 km/h (0 mph) when any of the following occur:
• The EBCM detects a malfunction in the vehicle speed sensor circuit.
• The ECM detects a loss of CAN communications with the EBCM.
• The BCM detects a loss of CAN communications with the ECM.
• The IPC detects a loss of class 2 communications with the BCM.
Is the ABS light lit ? Having the vehicle checked for DTC'S - diagnostic trouble codes would be the best first step to finding the problem . Could be a wheel speed sensor or ?????? .
All systems should reset after disconnecting and reconnecting a good charged battery. However, before going any further you should remove the dead battery, have it checked and either replace it or charge it out of the vehicle. Then, install it and see if that works. If not, you probably will have to replace the BCM. Jump starting a dead battery is a very bad idea unless it is done very carefully, and even then, it can cause damage to modules.
Try starting it in neutral. If it starts OK and every time, replace the range sensor/ neutral safety switch, on the transmission.. After that replace the RF wheel bearing/sensor. Have the codes cleared . See if the Communication code goes away.
Sounds like the BCM (body control module) has a loss of communication with the engine controller. You will need to have it scanned with a proper scan tool to retrive the fault codes that are stored in the memory...I hope this helps.
Sounds like a blown fuse to one of the computers, either the ECM (engine control computer) or the BCM (body control computer). The ECM fuse should be under the hood and the BCM fuse in the cabin. The U1064 means a loss of communication on the data line between computers (64 usually is the BCM). If the computers can't communicate they will shut down the engine and set trouble codes. The other issue could be a faulty ignition switch not allowing power to a computer (but not common for cavaliers or sunfires). If fuses are good, chances are you have a faulty computer somewhere in the data line, shorting out communication.