B1336 — Door Ajar RR Circuit Open #

Note: The code description may vary depending on the vehicle manufacturer.

• Door Ajar RR Circuit Open (Generic/OEM)
• Right Rear Door Ajar Switch Circuit Open (Ford, Lincoln, Mercury)
• RR Door Switch Open Circuit (GM, Chevrolet, Buick)
• Rear Right Door Ajar Input Circuit Open (Toyota, Lexus)
• Passenger Side Rear Door Ajar Signal Open (Chrysler, Dodge, Jeep)

Code summary for B1336 #

The B1336 diagnostic trouble code (DTC) indicates an electrical open circuit detected in the right rear (RR) door ajar switch or its associated wiring. This circuit is used by the vehicle’s Body Control Module (BCM) to monitor the open/closed status of the right rear door. When the circuit is open, the BCM cannot reliably determine if the door is closed, so it triggers the code. While this fault does not usually affect engine performance, it can lead to problems with interior lighting, vehicle security systems, or warning indicators on the dashboard. Understanding and resolving this code ensures proper vehicle operation and occupant safety features.

Common symptoms for code B1336 #

Drivers and technicians may notice several symptoms when the B1336 code is present. These are generally linked to the body electronics and convenience features, and may not always be immediately obvious unless the driver pays close attention. Common symptoms include:

• Right rear door ajar warning light remains on, even when the door is closed
• Interior dome light stays on or does not operate correctly
• Warning chimes for open door sound when all doors appear closed
• Doors may not lock automatically when driving
• Vehicle security system may not arm properly
• Possible battery drain if interior lights remain on

Most likely causes of B1336 #

Several issues can trigger this DTC, and some are more frequent than others. The most common problems relate to the electrical connections and components associated with the right rear door ajar circuit. Here’s an ordered list from most to least likely:

1. Faulty right rear door ajar switch (the switch itself is defective or worn)
2. Broken or damaged wiring between the switch and the Body Control Module (BCM)
3. Corroded or loose electrical connectors at the door or BCM
4. Misaligned door striker causing the switch not to actuate fully
5. Faulty or water-damaged BCM (rare, but possible in flood or high-humidity conditions)

Step-by-step diagnosis for code B1336 #

Accurate diagnosis is crucial to avoid unnecessary parts replacement. Follow this systematic approach to pinpoint the issue:

• Verify the code with a professional OBD-II/EOBD scan tool and check for any related codes.
• Inspect the right rear door for proper closure and alignment; ensure the door latches fully.
• Locate the right rear door ajar switch (usually near the latch mechanism) and check for physical damage.
• Test the switch function using a multimeter (check for continuity when the door is open/closed).
• Examine the wiring harness from the door switch to the BCM for visible damage, pinching, or corrosion.
• Check connectors for corrosion, bent pins, or looseness. Clean and secure as needed.
• If all checks pass, use a wiring diagram to test for continuity and voltage from the switch to the BCM.
• As a last step, consider BCM diagnostics per OEM procedures if all other components test good.

Possible repairs for B1336 #

Repairs should directly address the identified cause from the diagnostic process. The following solutions correspond to the most common issues:

• Replace the right rear door ajar switch if it fails continuity or is physically damaged.
• Repair or replace any damaged wiring or connectors between the switch and BCM.
• Clean corroded connectors using electrical contact cleaner; re-pin or replace connectors if needed.
• Realign the door and striker plate to ensure proper switch contact.
• If diagnosed, replace or reprogram the Body Control Module according to OEM specifications.

Is it safe to drive with code B1336? #

Yes, but with limitations. While this code does not typically affect the engine or basic drivability, it can compromise convenience and safety features such as interior lighting, door locks, and security alarms. If the interior lights stay on, battery drain is possible. It is safe for short-term use, but prompt repair is recommended to avoid inconvenience or potential security risks.

Vehicles most commonly affected by B1336 #

This code is most frequently observed in vehicles with advanced body electronics from the late 1990s onward. American and Asian manufacturers often use this code or a close variant. Commonly affected models include:

• Ford F-150, Fusion, Explorer, Escape
• Chevrolet Silverado, Equinox, Malibu
• Buick Enclave, LaCrosse
• Toyota Camry, Highlander, Tacoma
• Lexus RX, ES, IS
• Chrysler Town & Country, Pacifica
• Dodge Grand Caravan, Charger
• Jeep Grand Cherokee, Wrangler

Common mistakes and best practices for code B1336 #

Avoiding misdiagnosis and unnecessary part replacements is essential for a successful repair. Here are common pitfalls and tips for technicians and DIYers:

• Replacing the door ajar switch without testing the wiring or connectors first
• Overlooking corroded or loose connectors inside the door jamb
• Ignoring door alignment, which can prevent the switch from actuating properly
• Forgetting to clear the code and check for return after repairs
• Not using OEM wiring diagrams for accurate circuit tracing

Quick FAQ for code B1336 #

Have more questions? Here are quick answers to the most common concerns:

• Q: Will this code cause my car to fail inspection?
  A: Not typically, unless your local inspection program checks for all body codes. However, an illuminated warning light may be a concern.
• Q: Can I fix B1336 myself?
  A: If you have basic tools and experience, you can inspect the switch and wiring. For deeper electrical troubleshooting or BCM issues, professional help is recommended.