B1740
Low Severity (Level 1)Mirror Driver Horizontal Switch Circuit Short To Ground
B1740 usually means mirror Driver Horizontal Switch Circuit Short To Ground.
Can you still drive with B1740?
✅Safe to drive — this is an informational or minor issue. Schedule diagnosis at your convenience.
Typical repair cost: $60 – $500
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 won't adjust — stuck in current position
- Power mirrors blowing fuses when activated
- Mirror defrost/heater not working
- Zero voltage on the power mirror system circuit — short pulls signal to ground
Possible Causes
- Chafed or pinched wire in the power mirror system circuit — wire insulation worn through, copper touching vehicle chassis/ground
- Failed mirror motor with internal short to ground — most common when the component gets wet or overheats
- Corrosion in the electrical connector allowing current to leak to the connector shell/ground
- Damaged wiring harness where it passes through a body panel grommet or near a sharp metal edge
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 ($30-110 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, $143 diagnostic fee at shop)
- Repair or replace damaged section of wiring harness where short is located — solder and heat-shrink all connections, don't use crimp connectors on critical circuits ($175-311 depending on accessibility)
- If mirror motor is internally shorted, replace with a quality OEM or OEM-equivalent aftermarket unit ($50-400)
- Clean all ground points related to the power mirror system — remove bolt, sand contact surface to bare metal, apply dielectric grease, and torque to spec ($78-188 at shop)
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 B1740 mean?
B1740 stands for "Mirror Driver Horizontal Switch Circuit Short To Ground". B1740 usually means mirror Driver Horizontal Switch Circuit Short To Ground.
Can you drive with B1740?
Safe to drive — this is an informational or minor issue. Schedule diagnosis at your convenience.
How much does it cost to fix B1740?
Repair costs for B1740 typically range from $60 to $500, 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 ($30-110 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, $143 diagnostic fee at shop); Repair or replace damaged section of wiring harness where short is located — solder and heat-shrink all connections, don't use crimp connectors on critical circuits ($175-311 depending on accessibility).
Will B1740 clear itself?
Explore Repair Costs
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