B1735 — Mirror Driver Vertical Switch Circuit Short To Battery #

Please note: The label for this Diagnostic Trouble Code (DTC) may vary depending on the vehicle manufacturer (OEM — Original Equipment Manufacturer).

• B1735 — Mirror Driver Vertical Switch Circuit Short To Battery (Ford, Chrysler, GM)
• B1735 — Driver Side Mirror Vertical Adjustment Switch Circuit High (Toyota)
• B1735 — Outside Mirror Up/Down Switch Shorted to Power (Nissan)

Code Summary for B1735 #

The B1735 DTC points specifically to an issue with the vertical adjustment circuit of the driver’s side mirror, indicating a short to the battery voltage. In simple terms, the system has detected that the switch or wiring controlling the up-and-down movement of the driver’s mirror is receiving more power than it should, likely due to a direct connection (short) to the vehicle’s battery supply. This can interfere with proper mirror operation and, if left unchecked, may prevent correct positioning of the mirror. The code is most often triggered when the Body Control Module (BCM) or a similar control unit detects abnormal voltage in the circuit. While not immediately critical for vehicle safety, this code should not be ignored, especially if you rely on your power mirrors for daily driving or safety checks.

Common Symptoms for DTC B1735 #

When the B1735 code is active, you may notice a range of telltale signs related to the driver’s side power mirror. Sometimes the symptoms are subtle, but they can also be quite disruptive, especially if you frequently adjust your mirrors.

• Driver’s side mirror will not move up or down using the adjustment switch
• Mirror may move erratically or get stuck in one position
• Mirror adjustment switch feels hot to the touch
• Intermittent mirror operation
• Illuminated warning light or error message on the dashboard (in some vehicles)
• Clicking or buzzing sound from the mirror assembly

Most Likely Causes for DTC B1735 #

The B1735 code is most commonly caused by electrical faults, but several components could be to blame. Below are the most frequent culprits, listed in order of likelihood:

1. Damaged or pinched wiring harness to the mirror switch or motor, especially where wires pass through the door jamb
2. Faulty driver’s mirror vertical adjustment switch (internal short to battery voltage)
3. Short to power in circuit connectors due to moisture, corrosion, or poor repair work
4. Defective mirror motor assembly that has developed an internal short
5. Malfunctioning Body Control Module (BCM) or related control unit (rare)

Step-by-Step Diagnosis for B1735 #

Diagnosing a B1735 code involves tracing the electrical path from the switch to the motor and control module. Even if you’re not a master technician, following a logical sequence can help pinpoint the issue:

• Use an OBD-II scanner to verify the presence and history of the B1735 code, and clear the code to see if it returns.
• Visually inspect the wiring harness for obvious damage, especially where wires flex between the door and vehicle body.
• Check for moisture, corrosion, or bent pins in all related connectors (mirror switch, mirror assembly, and under-dash connections).
• Using a digital multimeter, measure voltage at the mirror switch and motor terminals with the ignition ON. Look for battery voltage where it shouldn’t be present.
• Disconnect the driver’s mirror switch and check if the code disappears. If so, the switch is likely shorted internally.
• If available, use wiring diagrams to isolate and test individual wires for continuity and shorts to power or ground.
• As a final step, consider testing or substituting the Body Control Module if all other components and wiring check out.

Possible Repairs for B1735 #

Once you’ve identified the source of the short, repairs for the B1735 code generally fall into one of these categories. Always address the root cause to prevent recurring issues:

• Repair or replace any damaged wiring or connectors, especially in the door harness area
• Replace the driver’s mirror vertical adjustment switch if it is found to be shorted internally
• Replace the driver side mirror motor assembly if it contains a short
• Clean and dry any corroded connectors, applying dielectric grease as appropriate
• Replace the Body Control Module (BCM) only if all other causes are eliminated and module failure is confirmed

Is It Safe to Drive with Code B1735? #

Yes, but with limitations. The B1735 code does not affect core driving safety systems like brakes or steering, so the vehicle can generally be driven without immediate risk. However, the inability to adjust your driver’s mirror vertically can reduce visibility and may increase blind spots. For optimal safety, it’s best to have the issue resolved as soon as possible, especially if you require frequent mirror adjustments or share your vehicle with other drivers.

Vehicles Most Commonly Affected by B1735 #

Based on field reports and OEM documentation, the B1735 code is most frequently encountered on certain models equipped with power mirrors and electronic adjustment switches. It is not exclusive to any one brand, but tends to appear in:

• Ford F-Series trucks and SUVs (F-150, Expedition, Explorer)
• Chevrolet Silverado and GMC Sierra pickups
• Chrysler and Dodge minivans (Grand Caravan, Pacifica)
• Toyota Camry and RAV4
• Nissan Altima and Maxima

Common Mistakes & Best Practices for B1735 #

When tackling a B1735 code, even experienced technicians can fall into certain traps. Here’s how to avoid the most frequent errors and ensure a lasting fix:

• Assuming the mirror motor is faulty without first checking the switch and wiring
• Overlooking damaged wires in the door jamb, where repeated opening and closing causes stress
• Replacing parts before performing basic voltage and continuity checks
• Ignoring moisture or corrosion in connectors, which can cause intermittent shorts
• Always use OEM or high-quality replacement parts to ensure compatibility and durability

Quick FAQ for B1735 #

The B1735 code raises a few common questions. Here are concise answers to help you move forward:

• Can I reset the B1735 code with a scan tool and have it stay off?
  If the underlying electrical issue is not resolved, the code will almost always reappear after a reset. Address the root cause for a permanent fix.
• Will disconnecting the battery clear the B1735 code?
  Disconnecting the battery may temporarily clear the code from some modules, but it does not repair the short. The code will return once the fault is detected again.