B1337
Door Ajar RR Circuit Short To Battery
Body Chassis/Safety Door Latch & Ajar Detection 🟢 Low — Fix at next service
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What This Actually Means
In plain language — no jargon

The rear right door's sensor circuit is shorted directly to battery voltage, causing the system to think the door is always sending a maximum signal. It's like a light switch stuck in the 'on' position, flooding the circuit with power instead of a controlled signal.

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Symptoms You May Notice
3 known symptoms for this code
Door ajar warning light stays on continuously
Rear right door lock may not function properly
Interior lights may not respond to door opening/closing
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Embedded Systems Insight
What the ECU/ECM is actually computing

The ECU monitors the door ajar switch circuit voltage, expecting it to toggle between ground (door closed) and a low signal voltage (door open). A short to battery causes the voltage to remain constantly high, exceeding normal thresholds. The ECU interprets this as a perpetual open-door condition or circuit malfunction.

Voltage & Parameter Thresholds

Parameter Normal Range Fault Condition
Door Switch Voltage 0V (closed) to 5V (open signal) Constant battery voltage (12V+)
Circuit Resistance Varies with switch state Shorted directly to positive battery line
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Diagnostic & DIY Fix Guide
Check these in order — from cheapest to most complex
1
Door ajar switch connector
Inspect and reseat the connector on the rear right door to eliminate corrosion or loose pin contact.
2
Door ajar switch
Replace the faulty switch located on the rear right door frame; it is likely internally shorted to battery.
3
Door wiring harness
Inspect the door harness for damaged insulation or pinched wires causing contact with battery voltage lines.