Brake On/Off Switch Out of Self-Test Range (Ford)
What does P1703 mean?
The P1703 code means the vehicle's onboard diagnostic system has detected: Brake On/Off Switch Out of Self-Test Range (Ford). This is a low severity code.
Common Symptoms
- Check Engine Light on
- Cruise control inoperative
- Torque converter clutch not locking up
- Brake lights stuck on or not working
- Shift interlock not releasing from Park
Probable Causes (Ranked by Likelihood)
- Faulty brake light switch Very High
- Brake switch out of adjustment High
- Corroded brake switch connector Moderate
- Damaged wiring at brake pedal area Low
Step-by-Step Diagnostic Procedure
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Check if the brake lights work properly when the pedal is pressed.
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Inspect the brake light switch at the top of the brake pedal arm for proper adjustment.
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Measure the brake switch output voltage with the pedal released and pressed.
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Check the brake switch connector for corrosion or damage.
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If the switch is adjustable, follow Ford's procedure to set the correct gap between the switch and pedal arm.
Frequently Asked Questions
Why does the brake switch affect the transmission?
The PCM uses the brake switch signal to control torque converter clutch lockup, shift timing, and cruise control. An incorrect signal disrupts these functions.
Is the brake light switch easy to replace?
Yes. On most Ford vehicles it clips onto a bracket above the brake pedal arm and can be replaced in minutes without tools.
Can a stuck brake switch drain my battery?
Yes. If the brake switch stays engaged, the brake lights remain on continuously, which can drain the battery overnight.