Electronic Control Modules - Service Information: Diagnosis RAM Cab & Chassis 3500 HD

DIAGNOSIS AND TESTING - DOOR MODULES

Any diagnosis of the door modules should begin with the use of a scan tool and the appropriate Diagnostic information. Refer to DIAGNOSIS AND TESTING .

Refer to the appropriate wiring information.

Scheme 142

1. Disconnect and isolate the battery negative cable.
2. Remove the trim panel from the inside of the front door. Refer to «PANEL, DOOR TRIM, REMOVAL»(ref-476497-S21058414162012060400000) .
3. Disconnect each of the electrical connectors from the connector receptacles of the door control module (1).
4. Remove the two screws that secure the door control module to the front door hardware module carrier.
5. Remove the door control module from the door hardware module carrier.

START-UP DIAGNOSTICS

When the DTCM is activated, the internal circuitry will undergo a diagnostic procedure. The controller will examine all inputs and outputs for short circuits to ground, short circuits to battery and open circuits and will also verify proper CPU and memory operation. If a fault is detected, a message will be sent out over the CAN C bus to the Cluster indicating that service is recommended.

After passing all diagnostic tests, the controller will receive and process inputs and produce the appropriate outputs. Proper monitoring of the controller inputs and outputs performance will continue.

DIAGNOSIS AND TESTING - HEATED SEAT MODULE

Note. Vehicles equipped with the heated seat option utilize a low voltage cut-off feature. This feature turns off power to the heated seat system anytime vehicle voltage is below 11.7 volts or above 15.5 volts. Be certain to check the vehicle electrical system for proper voltage anytime the heated seat system appears inoperative.

Note. If a Diagnostic Trouble Code (DTC) can not be verified, it is a good indication that an INTERMITTENT fault condition may be present. To help find an intermittent problem, sit in the seat in question and move around the heating elements within the seat while testing continuity. also wiggle the heated seat wire harness and electrical connectors while testing continuity.

Note. For complete circuit diagrams, refer to appropriate Wiring Information. Wiring Information includes wiring diagrams, connector pin-out and location views, details of wire harness routing and retention, splice and ground locations and proper wire and connector repair procedures.

1. Check the ignition switch fuse in the Totally Integrated Power Module. Repair as necessary.
2. Check the vehicles battery open-circuit voltage and charging system performance. If the vehicle's electrical system is defective or weak it may not be suppling sufficient energy to operate the heated seat or heated steering wheel system.
3. Using a scan tool, check for any Diagnostic Trouble Codes (DTCs) related to the Heated Seat Module (HSM). If any DTCs are found, repair as necessary. Refer to «DIAGNOSIS AND TESTING»(ref-476539-S31190329512012060400000) .
4. If there are no DTCs and the heated seat, vented seat or heated steering wheel system does not operate, refer to appropriate wiring information and repair as necessary.
5. If wiring is OK, replace the HSM.
6. When equipped with a leather wrapped heated steering wheel, verify the HSM is configured to the leather steering wheel option with a scan tool. Refer to «STANDARD PROCEDURE»(ref-476539-S01491447892012060400000) .

Scheme 143

Scheme 144

1. Disconnect the negative battery cable.
2. Disconnect the five electrical connectors (1) from the Heated Seat Module (HSM) located under the driver seat.
3. Remove the HSM (4) from the seat frame (2). Push the lock tab (1) toward the rear of the seat, then slightly lower the front of the HSM and pull it forward to disengage the rear retaining tabs (3).

DIAGNOSIS AND TESTING - MEMORY SEAT MODULE (MSM)

In order to obtain conclusive testing of the memory system, the Controller Area Network (CAN) data bus, and all of the electronic modules that provide inputs to, or receive outputs from the memory system components must be checked. Any diagnosis of the memory system/module should begin with, the use of a scan tool and the appropriate diagnostic service information. . Refer to DIAGNOSIS AND TESTING .

Refer to the appropriate wiring information for complete circuit schematic or connector pin-out information.

Note. Vehicles equipped with the memory/heated seat option utilize a low voltage cut-off feature. This feature turns off the 12v power to the power seat system anytime vehicle voltage is below 11.7v. Be certain to check the vehicle electrical system for proper voltage anytime the power seat system appears inoperative.

Before any testing of the power seat system is attempted, the battery should be fully-charged.

DIAGNOSIS AND TESTING - STEERING CONTROL MODULE

The hard wired circuits between components related to the Steering Control Module (SCM) may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair procedures, details of wire harness routing and retention, connector pin-out information and location views for the various wire harness connectors, splices and grounds.

However, conventional diagnostic methods will not prove conclusive in the diagnosis of the SCM or the electronic controls or communication between modules and other devices that provide some features of the SCM. The most reliable, efficient, and accurate means to diagnose the SCM or the electronic controls and communication related to SCM operation requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.

Scheme 145

On gasoline vehicles the Transmission Control Module (TCM) (2) may be sub-module within the Powertrain Control Module (PCM) (3).

Scheme 146

On Cab Chassis models equipped with the AS68RC transmission, the Transmission Control Module (TCM) has three electrical connectors and is located in the passenger compartment, underneath the left side of the dash panel.

On models equipped with the 68RFE transmission, the TCM is incorporated into the Powertrain Control Module (PCM).

DIAGNOSIS AND TESTING - FOBIK TRAPPED IN WIN

For more information, refer to TRANSMITTER, INTEGRATED KEY FOB, DIAGNOSIS AND TESTING .

Scheme 147

1. Disconnect and isolate the battery negative cable.
2. Remove the steering column cover opening. Refer to «COVER, STEERING COLUMN OPENING, REMOVAL»(ref-476497-S24155983532012060400000) .
3. Remove the four Wireless Ignition Node (WIN) retainers (1).
4. Disconnect the WIN electrical connector.
5. If equipped, remove the WIN antenna connector.
6. Remove the WIN from the instrument panel opening.