B1698
Mirror Driver/Passenger Switch Circuit Short To Ground
Body Chassis/Safety Mirror Control Circuit 🟢 Low — Fix at next service
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What This Actually Means
In plain language — no jargon

The mirror adjustment switch circuit is shorted to ground, meaning the electrical path is compromised and allowing unwanted current flow. Think of it like a light switch where the wire is touching metal, creating a shortcut that prevents normal operation.

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Symptoms You May Notice
3 known symptoms for this code
Mirror adjustment buttons not responding or functioning intermittently
Passenger or driver side mirror controls completely inoperative
Possible electrical burning smell or blown fuse related to mirror circuit
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Embedded Systems Insight
What the ECU/ECM is actually computing

The ECU monitors voltage levels on the mirror switch circuit, expecting specific voltage states when buttons are pressed or released. When a short to ground occurs, the voltage drops abnormally low or remains near 0V instead of the expected operating range. The ECU detects this continuous or intermittent low-voltage condition and sets the fault code.

Voltage & Parameter Thresholds

Parameter Normal Range Fault Condition
Switch Circuit Voltage 5V or 12V depending on circuit design Below 0.5V or continuous ground connection
Circuit Resistance Open or high resistance when inactive Less than 50 ohms to ground (short detected)
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Diagnostic & DIY Fix Guide
Check these in order — from cheapest to most complex
1
Fuse replacement
Check and replace the mirror circuit fuse if blown; refer to the fuse box diagram in your owner's manual.
2
Mirror switch assembly
Test the switch with a multimeter for continuity; replace if internal contacts are shorted or damaged.
3
Wiring harness and connectors
Inspect the mirror wiring for damaged insulation, pinched wires, or corroded connectors and repair or replace as needed.