B1702
Seat Driver Recline 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 recline switch isn't sending a signal to the ECU, like a light switch with a broken wire. The seat control system can't detect when you're trying to recline the seat forward.

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Symptoms You May Notice
3 known symptoms for this code
Seat recline forward function doesn't work
Seat control warning light or message on dashboard
Manual recline still works but electronic control fails
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Embedded Systems Insight
What the ECU/ECM is actually computing

The ECU monitors the voltage signal from the recline forward switch circuit. When the switch is pressed, it should pull the signal to ground, creating a voltage drop. An open circuit means no signal change is detected, indicating a broken connection or failed switch.

Voltage & Parameter Thresholds

Parameter Normal Range Fault Condition
Switch Signal Voltage 5V idle, 0V when activated No voltage change or stuck at 5V
Circuit Resistance < 10 ohms when closed Open circuit (infinite resistance)
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Diagnostic & DIY Fix Guide
Check these in order — from cheapest to most complex
1
Seat recline switch connector
Inspect and reseat the electrical connector at the seat base to ensure proper contact.
2
Wiring harness
Check the wiring from seat to ECU for breaks, corrosion, or loose connections under the seat.
3
Recline forward switch assembly
Replace the switch if connector and wiring are intact but no voltage signal is detected with a multimeter.