B2315 - Rear Left Door Module (RDM) Fault
This code indicates a fault in the rear left door module's communication or operation.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The rear left door isn't working right because the module that controls it is having communication issues; it might not open or close properly.
What the computer is actually seeing
The Body Control Module (BCM) detects no or incorrect signals from the rear left door module, indicating a communication break or operational issue.
What a healthy reading looks like
The rear left door module should send a signal at 0.5-4.5 volts when it operates correctly; anything outside this range or no signal at all can trigger the code.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 1Check the connectors and wiring at the rear left door module for damage or corrosion. Repair as needed. Decision: Is wiring intact? If yes, go to step 2. If no, fix wiring.
- 2Measure voltage at the rear left door module connector with key on, engine off. Expected voltage is between 0.5-4.5 volts during operation. Decision: Is voltage within range? If yes, go to step 3. If no, repair power or ground issues as needed.
- 3Test the rear left door module operation by activating it through the vehicle's controls. Listen for response. Decision: Does the module respond? If yes, the issue may be in the BCM. If no, replace the door module.
Common causes
- Bad connection or corrosion in wiring harness
- Faulty rear left door module
- Damaged door latch or actuator
- Short circuit or open circuit in the module
- Faulty Body Control Module (BCM)
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive my vehicle with this code?
Yes, but the rear left door will not operate properly until repaired.
Will this code come back after clearing?
It may return if the underlying issue isn't resolved.
How does this affect other systems?
Could affect door locks and window operations related to the rear left door.
Working a real vehicle right now?
Let DiagCoach walk you through it live with your specific symptoms, vehicle, and what you've already checked.
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