Loss Of Communication DTC'S Set In Multiple Modules During New Vehicle Prep/Service (08-012-04)

LOSS OF COMMUNICATION DTC'S SET IN MULTIPLE MODULES DURING NEW VEHICLE PREP/SERVICE

TECHNICAL SERVICE BULLETIN

SUBJECT

Loss Of Communication DTC's Set In Multiple Modules During New Vehicle Prep/Service

MODELS

2005 (LX) 300/Magnum

DISCUSSION

Diodes in cavity 31 and/or cavity 32 and/or cavity 33 in the Rear Power Distribution Center (RPDC), located in the trunk next to the battery, may become dislodged when the RPDC cover is removed using excessive side loading/force. V6 engine equipped vehicles have two diodes in the RPDC (cavities 31 and 33). V8 engine equipped vehicles have Three diodes in the RPDC (cavities 31, 32 and 33).

If the cavity 31 diode becomes dislodged when the RPDC cover is removed, the following issues will occur: You will lose the ignition run feed to the following modules/components: Occupant Restraint Control (ORC) module, Automatic Temperature Control (ATC) control head, Manual Temperature Control (MTC) & ATC blower motor, High Intensity Discharge (HID) module & associated sensors/headlamps, and Parktronics module. Loss of communication Diagnostic Trouble Codes (DTC) with these modules will be set. The airbag light will be illuminated in the instrument cluster. The Front Control Module (FCM) will report B2124-ignition run control circuit open.

If the cavity 32 diode becomes dislodged when the RPDC cover is removed, the following issues will occur: All modules that are capable will set loss of communication DTC's with the Transmission Control Module (TCM). The transmission will go into 2nd gear limp-in. The Anti-lock Brake System (ABS) light in the instrument cluster will be illuminated.

If the cavity 33 diode becomes dislodged when the RPDC cover is removed, no DTC's or any operator noticeable vehicle functions are affected. The cavity 33 diode provides charging system over voltage protection.

Before installing the cover on the RPDC, make sure all diodes and fuses are securely seated by pressing down on them. If a diode became completely separated from the RPDC cavity be aware the diodes are keyed and can only be inserted in one direction, the diode "arrow symbol" on top of diodes in slots 31 and 32 point toward the spare tire, slot 33 diode "arrow symbol" points to the rear of the vehicle. Special care must be using when installing the cavity 33 diode to insure proper orientation as its terminals will make contact in the reversed position before the key prevents full insertion and will cause the cavity 5 fuse to fail.

POLICY

Information Only.