had the check engine light come on last year which turned out to be just the gas cap but there was also U0140 showing up on my reader which i believe is the body control module. mentioned it when i was at the dealer a couple weeks later and they said that they couldn't find any codes. rechecked with mine and it was still there. now last week my engine light came on yet again which turned out to be the grill shutters and that U0140 code is still there.
does anyone know exactly what that module does? also any reason why it'd show up on my reader but not the dealers?
That code is for communication lost, not that the BCM is bad.
From Alldata:
U0140-LOST COMMINICATION WITH BODY CONTROL MODULE
The COMMUNICATION DIAGNOSTIC PROCEDURE
MUST be performed before replacing any component(s) or module(s). Perform the COMMUNICATION DIAGNOSTIC PROCEDURE.
Here is a description of the BCM:
DESCRIPTION
A Body Control Module (BCM) is an electronic control unit with a microcontroller that controls and integrates many of the main body electronic functions and features of the vehicle. Many of the functions and features provided by the BCM are possible because of numerous hard wired inputs and outputs, but most of these features are only possible or are enhanced because the BCM communicates electronically with other electronic modules in the vehicle as well as with a diagnostic scan tool using the Controller Area Network (CAN) data bus.
The BCM is a gateway between the high and low speed CAN data bus networks as well as a Local Interface Network (LIN) master node. This method of communication allows the sharing of sensor information, which reduces wire harness complexity, internal controller hardware and component sensor current loads. At the same time, this system provides increased reliability, enhanced diagnostics and allows the addition of many new feature capabilities. This method of communication is used by the BCM to acquire vehicle configuration data, including customer programmable features.
NOTE:There are no serviceable fuses are relays on this BCM.
If you want more info on the actual operation of the BCM, let me know.
