B1718
Seat Driver Forward Switch Circuit Open
Body Chassis/Safety Seat Controls 🟢 Low — Fix at next service
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What This Actually Means
In plain language — no jargon

The seat's forward adjustment switch isn't sending a signal to the car's computer, like a broken button that the system can't detect. This electrical connection is either loose, damaged, or completely disconnected.

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Symptoms You May Notice
3 known symptoms for this code
Seat forward/backward adjustment buttons don't work
No electrical response when pressing seat adjustment controls
Warning light or fault code displayed on dashboard
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Embedded Systems Insight
What the ECU/ECM is actually computing

The ECU monitors voltage and resistance across the seat forward switch circuit. When the switch is pressed, it should complete a circuit and change the voltage signal. An open circuit means no continuity is detected, indicating a broken wire or disconnected switch.

Voltage & Parameter Thresholds

Parameter Normal Range Fault Condition
Switch Circuit Continuity 0.5-2.0V when activated, 12V when inactive No voltage change or open circuit detected
Circuit Resistance 50-500 ohms when engaged Infinite resistance (open circuit)
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Diagnostic & DIY Fix Guide
Check these in order — from cheapest to most complex
1
Seat adjustment switch connector
Inspect and reseat the electrical connector at the switch base to restore contact.
2
Wiring harness for seat controls
Check for broken or pinched wires between the switch and seat motor, repairing or replacing as needed.
3
Seat forward adjustment switch assembly
Replace the faulty switch if continuity cannot be restored through connector cleaning or wire repair.