Sebring Sedan V6-2.7L VIN R (2004)
Seat Belt Control Module: Testing and Inspection
SEAT BELT CONTROL TIMER MODULE
The Seat Belt Control Timer Module (SCTM) is connected to the Body Control Module (BCM). Problems with the circuitry will be indicated by the seat
belt warning indicator lamp.
When the G-Sensor is at rest, current flows to the solenoids holding them back. The seat belt is movable. When the sensor reacts to the force of impact, it
stops current flow to the solenoids. The solenoids close in milliseconds, locking the seat belts.
The timer allows current to flow through the sensor and the solenoids for 30 minutes after the ignition is turned OFF. The 30 minute limit stops
excessive battery drain while the engine is not running.
Connected to the Door Ajar switches, the timer closes the circuit when a door opens and holds for 30 minutes after the door closes with the ignition
OFF. This is necessary so the seat belts can be managed after the ignition has been OFF for more than 30 minutes. Turning the key to the ACCESSORY,
RUN, or RUN/START position will also cause the timer to activate the solenoids.
DIAGNOSTIC MODE
For service purposes, the 30 minute timer can be reduced to 30 seconds by:
1. turning the ignition switch OFF.
2. Close the drivers door.
3. Cycle the ignition switch (key ON - key OFF) three times.
4. Open and close the drivers door three times.
NOTE: If the vehicle is tilted to a 45 degree angle, or if it is subjected to acceleration or deceleration of 0.7 G's or more in any direction, the G-Sensor
will lock the seat belts.
DETECTABLE FAULTS
The SCTM affords limited diagnostic capability including:
-
Solenoid shorted to ground.
-
Solenoid open.
-
Solenoid shorted to battery.
-
Internal fault.
-
No acceleration within the last 10 timer cycles (one timer cycle - key ON plus 30 minute minimum key OFF).
The seat belts themselves can demonstrate problems such as:
-
Both locked all the time.
-
Both locked with the ignition OFF, but not timed out.
-
Both seat belts function properly when the ignition is ON or the driver door is opened, but not when the driver door is opened.
-
Both seat belts function properly when the ignition is ON or the driver door is opened but not when the passenger door is opened.
-
Driver seat belt locked, passenger seat belt unlocked.
-
Passenger seat belt locked, driver seat belt unlocked.
These problems can be diagnosed using a Digital Volt/Ohm Meter (DVOM). Refer to Wiring Diagrams and the proper Body Diagnostic Procedures
manual.
SCTM CONDITIONS
CAUTION: Do not disconnect or connect the SCTM while the battery is connected.
NOTE: If the SCTM is required to be in the "Sleep" mode for testing, remove the 20 amp seat belt maxi-fuse in the Power Distribution Center (PDC)
for one minute. This will allow the SCTM to time out. Reinstall the fuse after one minute to proceed with testing.
BOTH SEAT BELTS LOCKED ALL THE TIME
1. Turn the ignition switch to the ACCESSORY position to ensure power to the SCTM and the module will not time out.
2. Using a DVOM, check for battery voltage at pin 4 and 5 of the SCTM 13-way connector. If no voltage is present, go to Step 3. If voltage is
present, go to Step 6.
3. Check fuse 13 in the PDC and fuse 15 in the Junction Block. If fuses are OK, go to Step 5. If either fuse is blown, replace. If fuse blows again, go
to Step 4.
4. Disconnect the SCTM 13-way connector and replace fuse. Check for fuse to blow. If fuse blows, check circuit for shorts to ground between the
SCTM and the fuse. If fuse does not blow, connect the SCTM 13-way connector and if the fuse blows, check for shorts to ground between the
SCTM and the seat belt solenoid. Repair as necessary.
5. If the voltage is OK, go to Step 6. If no voltage is detected, check for an open circuit between fuse and SCTM. Repair as necessary.
6. Check for voltage a the seat belt solenoid 13-way connector under the seat. If OK, test sole-noid(s) for voltage. If no voltage is present, check for
