2010 Cadillac CTS Sedan AWD V6-3.6L Page 638

2010 Cadillac CTS Sedan AWD V6-3.6L Page 638

Circuit/System Description

The memory seat module (MSM) controls the seat, recline, lumbar, and steering column motors via half bridges that are divided into 2 groups that

are connected to separate power rails internal to the module. The MSM connects all of the motor control circuits on each power rail to a common

reference point whenever they are not in operation. This reference point is biased to approximately 2.5 volts. The MSM checks to see if this

reference voltage is shorted to ground or battery before enabling any seat, lumbar, or steering column motor.

Conditions for Running the DTC

The MSM must be powered.

Conditions for Setting the DTC

B3920 01

The voltage on any power rail 1 motor control circuit exceeds 2.78 volts for 100 ms.

B3920 02

The voltage on any power rail 1 motor control circuit is below 1.47 volts for 100 ms.

B3921 01

The voltage on any power rail 2 motor control circuit exceeds 2.78 volts for 100 ms.

B3921 02

The voltage on any power rail 2 motor control circuit is below 1.47 volts for 100 ms.

Action Taken When the DTC Sets

The MSM will not allow operation of any motor on the power rail for which the DTC was set.