Where does power go in a BCM Body Control Module?
The power then flowed to the headlight switch, and from the headlight switch to each headlight. The wire used for the run from the fuse to the switch and from the switch to the headlights had to be a large enough gauge to handle the current load of the headlights.
Can a BCM switch turn off the headlights?
If so, the BCM can turn off the headlights to save battery power. In more complicated and more recent designs, car makers run a single wire to the multi function switch to control headlights, high beams, parking lamps, turn signals and hazards. How can they accomplish all that with a single wire? Simple, the switch contains several resistors.
How does the BCM work in a starter motor?
The transponder ignition key communicates with the receiver which then communicates the key code to the BCM. The body control module passes the key code on to the PCM for confirmation. If the key code is correct, the PCM sends a verification signal back to the BCM and the BCM supplies power to the control coil on the starter motor relay.
Can a bad body control module be rebuilt?
In the early days, replacing a bad body control module meant paying a small fortune for a new one from a dealer. That’s not the case anymore. Lots of companies offer rebuilt units to replace your bad body control module BCM. Should you get a BCM body control module with a unit from a junk yard? NO!
What to do if your BCM is on Blink?
Check the fuse box if you suspect that your vehicle’s BCM is on the blink. Make sure all the fuses are in good shape. If any are burnt out, replace them immediately.
Can a body control module be rebuilt from a bad BCM?
Secondly, the body control module must be the exact same part number as the bad BCM you’re replacing. A rebuilt body control module will most likely include upgrades to prevent the types of failures that occur in the original design.
What happens when a BCM is turned off?
Your vehicle performance may also be affected as the BCM communicates with other control modules in the vehicle. Parasitic drain is due to components in your vehicle continuing to run after the key is turned off.
If so, the BCM can turn off the headlights to save battery power. In more complicated and more recent designs, car makers run a single wire to the multi function switch to control headlights, high beams, parking lamps, turn signals and hazards. How can they accomplish all that with a single wire? Simple, the switch contains several resistors.