B1640
Low Severity (Level 1)Mirror Passenger Left Circuit Open
B1640 usually means mirror Passenger Left Circuit Open.
Can you still drive with B1640?
✅Safe to drive — this is an informational or minor issue. Schedule diagnosis at your convenience.
Typical repair cost: $60 – $400
Severity Level 1 — Low
This code indicates a minor issue that is unlikely to cause immediate driveability problems. You can typically continue driving but should have the vehicle inspected at your earliest convenience.
Common Symptoms
- Power mirrors not working — no response when activated
- Power mirrors working intermittently, then stopping completely
- Mirror defrost/heater not working
- Infinite resistance in the power mirror circuit — broken wire or disconnected connector
Possible Causes
- Broken wire or connector pin in the power mirror system harness — common at flex points like door jambs or where wiring moves
- Disconnected or loose electrical connector — may have been bumped during other repairs
- Failed mirror motor — internal open circuit from age, heat cycling, or vibration
- Corrosion completely severing a wire or connector terminal — green crust on copper wiring
- Wiring harness damage from rodent chewing — look for nesting material near the engine or under dash
Common Fixes
- Scan vehicle with a professional-grade OBD2 scanner to read all stored codes and freeze frame data — note the conditions when the code set ($21-131 at shop, free at auto parts store for basic scan)
- Visually inspect the power mirror system wiring harness and connectors — look for chafed wires, melted insulation, green corrosion, loose pins, or rodent damage (often free to check yourself, $77 diagnostic fee at shop)
- Trace the power mirror system wiring from connector to connector with a multimeter set to continuity/resistance mode — find and repair the break in the circuit ($123-384 labor for diagnosis and repair)
- Check and reseat all connectors in the power mirror system circuit — disconnect, inspect pins, clean with electrical contact cleaner, apply dielectric grease, and reconnect firmly ($13 DIY or $60 shop minimum)
- If mirror motor has failed internally (open circuit inside), replace it — don't try to repair sealed components ($50-400)
Estimated Repair Cost
These are estimated costs based on generic repair data. Actual costs may vary depending on your vehicle, location, and labor rates.
Frequently Asked Questions
What does B1640 mean?
B1640 stands for "Mirror Passenger Left Circuit Open". B1640 usually means mirror Passenger Left Circuit Open.
Can you drive with B1640?
Safe to drive — this is an informational or minor issue. Schedule diagnosis at your convenience.
How much does it cost to fix B1640?
Repair costs for B1640 typically range from $60 to $400, depending on your vehicle make, model, and local labor rates. Common fixes include: Scan vehicle with a professional-grade OBD2 scanner to read all stored codes and freeze frame data — note the conditions when the code set ($21-131 at shop, free at auto parts store for basic scan); Visually inspect the power mirror system wiring harness and connectors — look for chafed wires, melted insulation, green corrosion, loose pins, or rodent damage (often free to check yourself, $77 diagnostic fee at shop); Trace the power mirror system wiring from connector to connector with a multimeter set to continuity/resistance mode — find and repair the break in the circuit ($123-384 labor for diagnosis and repair).
Will B1640 clear itself?
Explore Repair Costs
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