BMW 645Ci Sunroof Control Module Replacement Cost

This is not particularly common, but it does occur. Electronic components fail at random, but some things can lead to early failure. Jump starting a battery backwards or improperly can lead to the early failure of many electronic components, especially control modules. In most cases, the sunroof control module should last the lifetime of the vehicle.

When diagnosing the sunroof control module, the technician will simply compare actual conditions to electronic conditions. In other words, If the technician notes that the sunroof motor is inactive, but the control module shows voltage to the motor, a discrepancy is noted. Discrepancies like this are commonly used as clues which map to the issue. If the technician finds that the issue originates with the control module, whether by physical or scan testing, the module will be verified defective and replaced.

Like any other control module, the location of the sunroof control module will be identified, and the technician will then begin removing all obstructing components needed to access and remove the control module. Once accessed and removed, the connectors are cleaned and inspected, and the new module will be installed. After all components are reassembled on the vehicle, the technician will program the control module, if needed, and test the operation of the system to ensure the customer complaint has been corrected. Sunroof modules will likely need to relearn the path of the sunroof and limits of travel before one-touch operation is possible.

When dealing with electronic systems, especially if the issue pertains to the control module, we recommend thorough diagnostics before replacing parts. In effort to correct an electronic failure, it would be very easy to spend hundreds of dollars replacing components before realizing the issue is more advanced. In the case of electronic failures, diagnostics is a must.

Every possible scenario related to the failure of the sunroof control module can be replicated by one or more failures within the sunroof control system. This means that the control module may be blamed for an external issue, or an external component may be blamed for an internal sunroof control module issue. When the issue has been routed to one circuit, the entire circuit should be tested to prove the diagnosis.

Except for the very advanced DIY mechanic with a strong understanding of computerized circuit diagnostics and testing, this repair should be left to a professional. Again, diagnostics of electronic systems are difficult for the untrained person to perform correctly. Unless safety and diagnostic methods are understood and followed properly, this should be left to a professional.