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B1387moderate severity✨ AI-generated

Passenger Door Module Circuit Low

The passenger door module is not communicating properly due to low voltage.

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)

Inside the passenger door, there's a module that controls features like windows and locks. If there's not enough power getting to it, it can’t work right and sends a trouble code.

What the computer is actually seeing

The body control module detects a low voltage signal (below 7 volts) from the passenger door module circuit when it should be receiving a normal operational voltage (around 12-14 volts when the vehicle is running).

What a healthy reading looks like

Normal voltage should be between 12-14 volts when the ignition is on; below 7 volts indicates a fault.

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.

  1. 11. Inspect the wiring and connectors at the passenger door module for damage or corrosion. If any issues are found, repair or replace as necessary. Decision: If wiring is good, proceed to step 2; if damaged, fix and retest.
  2. 22. Measure the voltage at the passenger door module connector. You should see 12-14 volts with the ignition on. Decision: If voltage is normal, go to step 3; if low, check for open circuits, bad grounds, or fuse issues.
  3. 33. If the module still fails to operate correctly with normal voltage present, replace the passenger door module. Decision: If the new module resolves the issue, you're done; if not, reevaluate the wiring and connections.

Common causes

  • Damaged wiring or connectors in the door harness
  • Corroded terminals at the door module
  • Faulty passenger door module itself

Typical repair cost

$$$

Related codes

Frequently asked questions

Is it safe to drive with this code active?

Yes, you can drive, but the passenger door features may not work properly.

Will this code come back after clearing?

If the underlying issue isn't fixed, it will likely return.

What happens if I ignore this code?

Ignoring it could lead to the passenger door features failing completely.

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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