Dodge Ram Truck 1500-2500-3500. Manual — part 311

BODY VERIFICATION TEST - VER 1

Diagnostic Test

1.

PERFORM BODY VERIFICATION TEST

NOTE: If the SKIM, PCM or FCM was replaced, refer to the service information for proper programming pro-
cedures.

1. Disconnect all jumper wires and reconnect all previously disconnected components and connectors.

2. Ensure that all accessories are turned off.

3. Ensure that the battery is fully charged.

4. If the Instrument Cluster was replaced, disconnect the negative battery cable for 5 seconds to power down the
FCM. Then, reconnect the battery negative cable and turn the ignition on for 15 seconds to allow the Instrument
Cluster to learn the VIN.

5. If the Instrument Cluster was replaced and the vehicle is equipped with VTSS, cycle the key in the driver door
cylinder lock switch to enable VTSS.

6. Program the tire size, the country code, the radio EQ setting, all of the RKE transmitters (if RKE Module was
replaced), and all other options as necessary.

7. If any HVAC door actuator circuits were repaired, run the Actuator Circuit Test by selecting the following from
the DRBIII

T

menu: Select HVAC, System Tests, and Actuator Circuit Test. Allow the test to run to completion

before proceeding.

8. If any HVAC door actuators were replaced/door linkage was repaired, run the HVAC Door Recalibration by
selecting the following from the DRBIII

T

menu: Select HVAC, System Tests, and HVAC Door Recalibration. Allow

the test to run to completion before proceeding.

9. With the DRBIII

T

, record and erase all DTC’s from ALL modules.

10. Start and run the engine for 2 minutes while operating all functions of the system that caused the original
concern.

11. Turn the ignition off, wait 5 seconds, then turn the ignition on. Using the DRBIII

T

, read DTC’s from ALL mod-

ules.

Are DTCs present in any module or is the original condition still present?

Yes

>> The repair is not complete. Refer to the related category for the DTC or symptom that is still present.

No

>> The repair is complete.

8E - 116

ELECTRONIC CONTROL MODULES - SERVICE INFORMATION

DR/DH

REMOVAL

1. Disconnect and isolate the battery negative cable

(3).

2. Partially remove the Integrated Power Module

(IPM) (4) from the engine compartment (Refer to 8
-

ELECTRICAL/POWER

DISTRIBUTION/INTE-

GRATED POWER MODULE - REMOVAL).

3. Remove the Front Control Module (FCM) retaining

screws.

4. Using both hands, separate the FCM from the IPM

assembly disengaging the 49-way electrical con-
nector and remove the FCM from the vehicle.

INSTALLATION

1. Install the Front Control Module (FCM) onto the

Integrated Power Module (IPM) (4) by pushing the
49-way electrical connector straight in.

2. Install the FCM retaining screws. Torque the

screws to 7 in. lbs.

3. Install the IPM (Refer to 8 - ELECTRICAL/POWER

DISTRIBUTION/INTEGRATED POWER MODULE -
INSTALLATION).

4. Connect the battery negative cable.

5. Verify normal vehicle operation.

DR/DH

ELECTRONIC CONTROL MODULES - SERVICE INFORMATION

8E - 117

MODULE-HEATED SEATS

DESCRIPTION

The heated seat module (2) is also known as the Seat
Heat Interface Module. The heated seat module is
located under the drivers front seat cushion, where it
is secured to a mounting bracket. The heated seat
module has a single connector receptacle (3) that
allows the module to be connected to all of the
required inputs and outputs through the seat wire har-
ness.

The heated seat module is an electronic microproces-
sor controlled device designed and programmed to
use inputs from the battery, the two heated seat
switches and the two heated seat sensors to operate
and control the heated seat elements in both front
seats and the two heated seat indicator lamp Light-
Emitting Diodes (LEDs) in each heated seat switch.
The heated seat module is also programmed to per-
form self-diagnosis of certain heated seat system functions and provide feedback of that diagnosis through the
heated seat switch indicator lamps.

The heated seat module cannot be repaired. If the heated seat module is damaged or faulty, the entire module must
be replaced.

OPERATION

The heated seat module operates on fused battery current received from the integrated power module. Inputs to the
module include a resistor multiplexed heated seat switch request circuit for each of the two heated seat switches
and the heated seat sensor inputs from the seat cushions of each front seat. In response to those inputs the heated
seat module controls battery current feeds to the heated seat elements and sensors, and controls the ground for the
heated seat switch indicator lamps.

When a heated seat switch (Driver or Passenger) is depressed a signal is received by the heated seat module, the
module energizes the proper indicator LED (Low or High) in the switch by grounding the indicator lamp circuit to
indicate that the heated seat system is operating. At the same time, the heated seat module energizes the selected
heated seat sensor circuit and the sensor provides the module with an input indicating the surface temperature of
the selected seat cushion.

The Low heat set point is about 36° C (96.8° F), and the High heat set point is about 42° C (107.6° F). If the seat
cushion surface temperature input is below the temperature set point for the selected temperature setting, the
heated seat module energizes an N-channel Field Effect Transistor (N-FET) within the module which energizes the
heated seat elements in the selected seat cushion and back. When the sensor input to the module indicates the
correct temperature set point has been achieved, the module de-energizes the N-FET which de-energizes the
heated seat elements. The heated seat module will continue to cycle the N-FET as needed to maintain the selected
temperature set point.

If the heated seat module detects a heated seat sensor value input that is out of range or a shorted or open heated
seat element circuit, it will notify the vehicle operator or the repair technician of this condition by flashing the High
and/or Low indicator lamps in the affected heated seat switch. (Refer to 8 - ELECTRICAL/HEATED SEATS - DIAG-
NOSIS AND TESTING) for flashing LED diagnosis and testing procedures. (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/MEMORY HEATED SEAT/MIRROR MODULE - DIAGNOSIS AND TESTING) for
heated seat module diagnosis and testing procedures.

8E - 118

ELECTRONIC CONTROL MODULES - SERVICE INFORMATION

DR/DH

DIAGNOSIS AND TESTING

HEATED SEAT MODULE

If a heated seat fails to heat and one or both of the indicator lamps on a heated seat switch flash, (Refer to 8 -
ELECTRICAL/HEATED SEATS - DIAGNOSIS AND TESTING) for flashing LED diagnosis and testing procedures. If
a heated seat heats but one or both indicator lamps on the heated seat switch fail to operate, test the heated seat
switch. (Refer to 8 - ELECTRICAL/HEATED SEATS/DRIVER HEATED SEAT SWITCH - DIAGNOSIS AND TEST-
ING) for heated seat switch diagnosis and testing procedures. If the heated seat switch checks OK, proceed as
follows.

1. Check the heated seat element (Refer to 8 - ELECTRICAL/HEATED SEATS/HEATED SEAT ELEMENT - DIAG-

NOSIS AND TESTING).

2. Check the heated seat sensor (Refer to 8 - ELECTRICAL/HEATED SEATS/HEATED SEAT SENSOR - DIAG-

NOSIS AND TESTING).

3. Check the heated seat switch (Refer to 8 - ELECTRICAL/HEATED SEATS/DRIVER HEATED SEAT SWITCH -

DIAGNOSIS AND TESTING).

NOTE: Refer to Wiring for the location of complete heated seat system wiring diagrams and connector pin-
out information.

4. Using a voltmeter, backprobe the heated seat module connector, do not disconnect. Check for voltage at the

appropriate pin cavities. 12v should be present. If OK go to Step 5, if Not, Repair the open or shorted voltage
supply circuit as required.

5. Using a ohmmeter, backprobe the appropriate heated seat module connector, do not disconnect. Check for

proper continuity to ground on the ground pin cavities. Continuity should be present. If OK replace the heated
seat module with a known good unit and retest system, if Not OK, Repair the open or shorted ground circuit as
required.

REMOVAL

1. Position the driver seat to the full rearward and inclined position.

2. Working under the driver front seat, remove the two heated seat module retaining screws. Due to the fact that

the retaining screws are installed with the seat cushion pan removed, a small right angle screwdriver will be
required to access and remove the screws.

3. Disconnect the seat wire harness connector from the connector receptacle on the back of the heated seat mod-

ule. Depress the connector retaining tab and pull straight apart.

4. Remove the heated seat module from under the front seat.

INSTALLATION

1. Position the heated seat module under the front seat.

2. Connect the seat wire harness connector on the connector receptacle on the back of the heated seat module.

3. Working under the driver front seat, install the heated seat module retaining screws.

4. Re-position the driver seat.

DR/DH

ELECTRONIC CONTROL MODULES - SERVICE INFORMATION

8E - 119