1999 Chrysler Concorde, Intrepid, LHS & 300M Body Control Module: A Guide to Failures and Programming

Symptoms of a Failing Body Control Module

A failing BCM on a 1999 Chrysler Concorde, Dodge Intrepid, Chrysler LHS, or Chrysler 300M often leads to a variety of confusing electrical issues. Because the BCM controls so many different systems, symptoms can be widespread and intermittent. You might notice one or several of the following problems:

• Erratic Interior/Exterior Lights: Headlights, taillights, or interior lights may flicker, stay on when they should be off, or not turn on at all.
• Malfunctioning Power Accessories: Power windows, door locks, and mirrors may work intermittently or stop responding completely.
• Instrument Cluster Problems: Gauges on the dashboard (like the speedometer or fuel gauge) may behave erratically, drop to zero, or stop working entirely. Warning lights might illuminate for no reason.
• Security System and Starting Issues: The factory alarm may go off randomly, or the keyless entry may fail. In some cases, a faulty BCM can interfere with the Sentry Key Immobilizer System (SKIS), preventing the car from starting.
• Unexplained Battery Drain: A faulty BCM can fail to shut down certain circuits, leading to a parasitic draw that drains the battery overnight.
• Windshield Wiper Problems: Wipers may not turn on, may get stuck in one position, or may activate on their own.

A technician with a professional scan tool can look for specific Diagnostic Trouble Codes (DTCs) related to the BCM. Common codes may include communication errors (U-codes) or body-specific faults (B-codes). A code like P1695 (No BCM Bus Messages) can also point to a BCM communication problem.

Known Issues, TSBs, and Recalls

For the 1999 model year, there are no specific recalls or Technical Service Bulletins (TSBs) that directly target the Body Control Module itself for these vehicles. However, several TSBs and owner complaints from the era mention electrical issues that could be related to a failing BCM. For example, TSB #0803100 for the 1999 Chrysler LHS addresses an issue where a power window sticks in the up position, a function controlled by the BCM. Additionally, NHTSA complaints for the 1999 Chrysler LHS describe incidents where all dashboard gauges stopped working and the driver's seat began moving on its own, which are classic symptoms of BCM failure. There were also recalls for issues like seat back recliners and ignition-park interlocks, but these are separate mechanical systems not directly tied to BCM failure.

Buying a Used Body Control Module

Purchasing a used BCM can be a cost-effective solution, but it requires careful attention to detail. Since these vehicles are from the same platform, the modules are often interchangeable, but the part number is the most critical factor.

• Match the Part Number Exactly: The most important step is to match the OEM part number on your original BCM with the used unit. The vetted part numbers for these vehicles include 04606936AC and 04606936AD. Other compatible numbers may exist. Do not rely on the vehicle model alone.
• Inspect for Damage: When you receive the used module, inspect the case and connectors for any signs of corrosion, water damage, or physical trauma. These can indicate a pre-existing problem.
• Understand the Total Cost: The price of the used module is only part of the total cost. You MUST factor in the expense of having it professionally programmed to your vehicle.
• Why Used OEM is Often Better: For a critical component like the BCM, a used Original Equipment (OEM) part is often more reliable than a new, cheap aftermarket unit. OEM modules are built to the manufacturer's exact specifications for durability and performance.

Replacement Location and Procedure

The Body Control Module in the 1999 Concorde, Intrepid, LHS, and 300M is located inside the passenger compartment, under the driver's side of the dashboard. It is attached to the back of the interior fuse box, also known as the Junction Block.

1. Disconnect the Battery: Always disconnect the negative battery terminal before beginning any work on the vehicle's electrical system.
2. Access the Module: Remove the lower dashboard trim panel and knee blocker reinforcement under the steering column to gain access to the Junction Block.
3. Remove the Junction Block: Unbolt the Junction Block assembly from its mounting bracket on the dash panel.
4. Disconnect and Separate: Disconnect the wire connectors from the BCM. Remove the screws holding the BCM to the Junction Block, then slide the BCM off the Junction Block.
5. Installation: Installation is the reverse of removal. Attach the new BCM to the Junction Block, secure the assembly, reconnect all wiring, and re-install the trim panels before reconnecting the battery.

Required Programming After Installation

This is the most critical step of the replacement process. A replacement BCM, whether new or used, will not work correctly by simply plugging it in. It must be programmed to your specific vehicle.

• Anti-Theft System (SKIS): The BCM is a key part of the Sentry Key Immobilizer System (SKIS). The module stores vehicle-specific security information and must be synchronized with your vehicle's Powertrain Control Module (PCM) and programmed transponder keys. If this is not done, the engine will likely start and then immediately stall, or not crank at all.
• Vehicle Options: The BCM must also be configured for the specific options on your car, such as keyless entry, the type of lighting, and other power accessories.
• Who Can Program It?: This programming requires a specialized diagnostic tool. For these vehicles, it was originally the dealership's DRB III scan tool. 🎬 Watch: How to program the SKIM module using a DRB III tool. While some advanced automotive locksmiths or independent repair shops may have tools that can perform this function, a trip to a Chrysler/Dodge dealership is the most certain way to ensure it is done correctly. Do-it-yourself programming is not an option for the BCM itself. Some mail-in services offer to 'clone' your original BCM's data to a replacement unit, which can make the new part plug-and-play.

Cost Comparison

Frequently Asked Questions (FAQ)