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Does New BCM have to be Flashed by the Dealer?
08-22-2012, 06:13 PM
#23
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well i was trying to fix the windows/radio cutting out by adding solder to the "T" and like an idiot i did not dissconnect the battery or the BCM. I accidently let solder lay across the circuit board and heard a crackle. Now the car wont start. Heres the thread i started
https://ls1tech.com/forums/pcm-diagn...l#post16648617
https://ls1tech.com/forums/pcm-diagn...l#post16648617
08-23-2012, 01:01 PM
#26
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Whitebird can you tell me where to find it online NEW? i was going to go to the dealership tomorrow but if i can save $150 that would be sweet!
08-23-2012, 01:41 PM
#27
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i found it - gmpartsdirect, however it doesnt say new or if it is keyless entry or not. i found a cheaper one on amazon after shipping though. It says remanufactured so i assume that is the same as new so it will be ready to memorize my key the first time i use it. would you think that also? The last thing i want to do is accidently buy a used one that wont even work with my key.
08-24-2012, 07:20 AM
#28
gmpartsdirect sells only GM OEM parts. In most cases that means new although there are some GM-branded rebuilt items such as starters and alternators. Basically they sell the same thing you would get from the dealer. Just watch out for their shipping and handling charges... they tend to make their profit from large S/H charges. In this case, the BCM will be new in box and includes both keyless entry and factory alarm functions.
I had not heard of rebuilt BCMs and I would be cautious about buying one. The BCM can only be programmed once (when new) so I would be curious how a rebuilder could get around that.
I had not heard of rebuilt BCMs and I would be cautious about buying one. The BCM can only be programmed once (when new) so I would be curious how a rebuilder could get around that.
08-26-2012, 03:24 PM
#31
The original part numbers have been superseded. Originally there were different BCM part numbers for different options but at some point GM decided there was no need to carry multiple parts so the current part number supports all options (AU0 = keyless entry, UA6 = factory alarm system). The one you will get will work regardless of what options you have.
10-11-2012, 09:47 AM
#32
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The new BCM does have to be programmed. I went through this myself. Plugging the new one in and turning the key does nothing. Trust me I tried multiple times. When I replaced mine after I put the new one in and turned the key nothing happened. Tried many times the car would not ding, click, flash, turnover, nothing. Took it to the dealer and watched them program it with the tech 2, car started right up.
10-11-2012, 10:25 AM
#33
Sorry, but you could not be more wrong. A new BCM does not need to be programmed other than to match to the ignition key first used (which is completely automatic).
Not only does the factory service manual specify exactly how to initialize a new BCM (insert key and turn on ignition) but I have done it myself as have others who have posted in this thread.
Your car may have had a VATS bypass previously installed which could have prevented the initialization from working properly.
Not only does the factory service manual specify exactly how to initialize a new BCM (insert key and turn on ignition) but I have done it myself as have others who have posted in this thread.
Your car may have had a VATS bypass previously installed which could have prevented the initialization from working properly.
10-11-2012, 10:50 AM
#34
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No bypass installed. Had vats tested numerous times at the gm dealer I worked for and no problems there. Bought a brand new BCM straight from gm. Installed it, tried to start the car and it did nothing at all. Watched the tech program aka flash new BCM with tech 2 and the car started right up. That was my personal experience so that's why I say it has to be flashed. Maybe there is differences from year to year with the BCM. Idk...
10-11-2012, 11:06 AM
#35
Same installation procedure for all 98-02 F-bodies. The GM service manual is quite specific on the procedure:
Are you sure you're not thinking of a PCM rather than a BCM? The reason I ask is because the BCM doesn't even connect to a Tech 2 programmer for diagnostics let alone programming. BCM Diagnostics are done in the car using the SECURITY light in the instrument cluster to flash diagnostic codes:
Body Control Module (BCM) Programming/RPO Configuration
Important
Any new body control module (BCM) will automatically program to the resistance of the key (or interrogator setting) being used at the first ignition ON cycle. This can only be done once for the life of the module.
A new BCM is not programmed. Before the system will function properly it must be programmed to the code that matches the customer's keys.
1. Install the new BCM. Refer to Body Control Module Replacement
2. Insert one of the customer's keys into the ignition cylinder and turn it to the on position. Its good to start the engine at this time to verify system operation.
3. Observe the SECURITY indicator lamp for the following:
- The indicator lamp lights for approximately 5 seconds and then goes out. This indicates that the BCM is programmed properly.
- The indicator lamp flashes at a rate of one flash per second until the ignition is off. This indicates that the BCM did not program and the system components, wiring and contacts should be checked for a fault.
Important
Any new body control module (BCM) will automatically program to the resistance of the key (or interrogator setting) being used at the first ignition ON cycle. This can only be done once for the life of the module.
A new BCM is not programmed. Before the system will function properly it must be programmed to the code that matches the customer's keys.
1. Install the new BCM. Refer to Body Control Module Replacement
2. Insert one of the customer's keys into the ignition cylinder and turn it to the on position. Its good to start the engine at this time to verify system operation.
3. Observe the SECURITY indicator lamp for the following:
- The indicator lamp lights for approximately 5 seconds and then goes out. This indicates that the BCM is programmed properly.
- The indicator lamp flashes at a rate of one flash per second until the ignition is off. This indicates that the BCM did not program and the system components, wiring and contacts should be checked for a fault.
Perform the following steps to enter the BCM diagnostic mode:
- Turn the ignition switch to the RUN position.
- Turn the ignition switch to the OFF position.
- Remove the Radio fuse 17 from the I/P fuse block.
- Turn the ignition switch to the ACCY position (the BCM sounds 1 or 2 audible warning tones).
- Within five seconds, turn the ignition switch to the OFF position and immediately (within 1 second) back to the ACCY position (the BCM sounds three audible warning tones to signal entry into the diagnostic mode).
The BCM will begin flashing trouble codes four seconds after entering the diagnostic mode. Each flash of the security indicator lamp on the IPC represents a number. For example, one flash followed by two quick flashes represents code 12. Each code is displayed three times before the next code is displayed. Stored DTCs are displayed in numerical order. Once the last code is displayed, the list begins again with the first code. The display continues until the diagnostic mode is exited
- Turn the ignition switch to the RUN position.
- Turn the ignition switch to the OFF position.
- Remove the Radio fuse 17 from the I/P fuse block.
- Turn the ignition switch to the ACCY position (the BCM sounds 1 or 2 audible warning tones).
- Within five seconds, turn the ignition switch to the OFF position and immediately (within 1 second) back to the ACCY position (the BCM sounds three audible warning tones to signal entry into the diagnostic mode).
The BCM will begin flashing trouble codes four seconds after entering the diagnostic mode. Each flash of the security indicator lamp on the IPC represents a number. For example, one flash followed by two quick flashes represents code 12. Each code is displayed three times before the next code is displayed. Stored DTCs are displayed in numerical order. Once the last code is displayed, the list begins again with the first code. The display continues until the diagnostic mode is exited
10-16-2012, 01:29 PM
#36
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Same installation procedure for all 98-02 F-bodies. The GM service manual is quite specific on the procedure:
Are you sure you're not thinking of a PCM rather than a BCM? The reason I ask is because the BCM doesn't even connect to a Tech 2 programmer for diagnostics let alone programming. BCM Diagnostics are done in the car using the SECURITY light in the instrument cluster to flash diagnostic codes:
Are you sure you're not thinking of a PCM rather than a BCM? The reason I ask is because the BCM doesn't even connect to a Tech 2 programmer for diagnostics let alone programming. BCM Diagnostics are done in the car using the SECURITY light in the instrument cluster to flash diagnostic codes:
04-29-2013, 07:46 PM
#38
Hello All!
I am getting ready to purchase a BCM from Amazon; they are cheaper than GM Parts Direct after their outrageous shipping and handling charges. I have two questions:
1.) I noticed in the description for the one from Amazon it says it is remanufactured. I would rather buy new, but I have a feeling the one from GM Parts Direct or a dealer will still be re-manufactured. Does anyone know for sure if the one from GM Parts Direct or a dealer would be a re-man or new unit? Here is the Amazon link if anyone wants to look at it:
2.) In trying to diagnose the intermittent "no start" problem with my '01 SS I bypassed the Vats. Can I leave the bypass in place and let the "new" BCM learn the resistance from the bypass instead of the key? In my thinking the BCM won't know the difference between the bypass and the key because it's just looking for a resistance value.
Thanks in advance for the help!!
I am getting ready to purchase a BCM from Amazon; they are cheaper than GM Parts Direct after their outrageous shipping and handling charges. I have two questions:
1.) I noticed in the description for the one from Amazon it says it is remanufactured. I would rather buy new, but I have a feeling the one from GM Parts Direct or a dealer will still be re-manufactured. Does anyone know for sure if the one from GM Parts Direct or a dealer would be a re-man or new unit? Here is the Amazon link if anyone wants to look at it:
2.) In trying to diagnose the intermittent "no start" problem with my '01 SS I bypassed the Vats. Can I leave the bypass in place and let the "new" BCM learn the resistance from the bypass instead of the key? In my thinking the BCM won't know the difference between the bypass and the key because it's just looking for a resistance value.
Thanks in advance for the help!!
04-30-2013, 07:27 AM
#39
1) I doubt you'll find anyone with a new BCM these days. There wouldn't be enough demand to make a production run economical so rebuilding older stock is the only option. But that shouldn't be a problem - it comes with a 12 month 12,000 mile warranty so they are pretty confident that they did it right.
2) As long as your bypass resistors are within tolerance for one of the 14 preset values, I see no reason why it wouldn't work. The BCM sees the resistance - it has no way to differentiate between a key pellet and an external resistor. Just make sure the key is in the ignition so that the "key in" signal is triggered as well.
2) As long as your bypass resistors are within tolerance for one of the 14 preset values, I see no reason why it wouldn't work. The BCM sees the resistance - it has no way to differentiate between a key pellet and an external resistor. Just make sure the key is in the ignition so that the "key in" signal is triggered as well.
04-30-2013, 12:20 PM
#40
Whitebird00,
Thank you for the response! I was thinking the same thing that pretty much all of the BCMs that would be available today would be re-mans, but wanted to confirm that.
I know the vats bypass was successful because it will start so I am going to leave the bypass in so that the VATS doesn't leave me stranded someday. I will make sure the key is in the ignition so it sees that signal.
Thanks again!
Thank you for the response! I was thinking the same thing that pretty much all of the BCMs that would be available today would be re-mans, but wanted to confirm that.
I know the vats bypass was successful because it will start so I am going to leave the bypass in so that the VATS doesn't leave me stranded someday. I will make sure the key is in the ignition so it sees that signal.
Thanks again!