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P0703ModeratePowertrain

P0703 on 2004-2007 Chevrolet Malibu — Brake Switch B Circuit Malfunction

1 vehicles · 1 makes · $30-$180 repair

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Most Reported On

2004-2007Chevrolet Malibu

P0703 is an OBD-II diagnostic trouble code meaning “Brake Switch B Circuit Malfunction.” This code means the engine/transmission computer detected an out-of-range or implausible signal from the brake switch (circuit B). The brake switch tells the PCM/TCM when the brakes are applied, which affects cruise control, torque converter lockup, and certain shift and idle strategies. A faulty signal can cause issues like cruise control not working, harsh shifts, or the converter not unlocking. This code is most commonly reported on 2004-2007 Chevrolet Malibu, with repair costs ranging from $30 to $180.

On This Page

  • Common Causes
  • Repair Cost
  • Vehicles (1)
  • Related Codes
  • FAQ
  • Sources (1)
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Common Causes

1Faulty brake light switch
2Misadjusted brake switch
3Open or shorted brake switch wiring
4Corroded or loose connector at the switch
5Blown brake circuit fuse
6PCM/TCM input fault

Typical Repair Cost

$30 - $180

Based on 1 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.

Diagnostic Tools

To diagnose P0703, you'll need an OBD-II scanner. Here are our recommendations at every price point.

Budget Pick$10–$20

ANCEL AD310 Classic OBD-II Scanner

by ANCEL

A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).

  • Read & clear engine codes
  • View freeze frame data
  • I/M readiness status
  • No batteries or app needed
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Best Value$90–$120

BlueDriver Pro Bluetooth Scanner

by BlueDriver

Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.

  • Enhanced diagnostics (ABS, SRS, transmission)
  • Repair Reports with verified fixes
  • Smog check readiness
  • Free app (iOS & Android)
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Advanced$180–$230

LAUNCH CRP123X OBD-II Scanner

by LAUNCH

A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.

  • Engine, transmission, ABS, SRS diagnostics
  • Live data stream & graphing
  • AutoVIN for vehicle identification
  • Free lifetime updates via Wi-Fi
Check Price on Amazon
Professional$350–$450

Autel MaxiCOM MK808S Diagnostic Tool

by Autel

Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.

  • All-system diagnostics (25+ modules)
  • Bi-directional control & active tests
  • Oil reset, EPB, BMS, TPMS, injector coding
  • 7-inch touchscreen with Android OS
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Vehicles Affected (1)

Chevrolet P0703 page →
MalibuModerate

Brake Light Switch Failure and Stoplamp Circuit Problems Causing Cruise Control and Shift Interlock Issues

2004-2007$30-$1800 reports

Related Codes (8)

P0700Transmission Control System MalfunctionP0701Transmission Control System Range/PerformanceP0020Camshaft Position 'A' Actuator Circuit (Bank 2)P0034Turbocharger/Supercharger Bypass Valve Control Circuit LowP0035Turbocharger/Supercharger Bypass Valve Control Circuit HighP003ATurbocharger/Supercharger Boost Control 'A' Position Exceeded Learning LimitP0046Turbocharger/Supercharger Boost Control 'A' Circuit Range/PerformanceP0089Fuel Pressure Regulator 1 Performance

FAQ

What does P0703 mean?

P0703 stands for "Brake Switch B Circuit Malfunction." This code means the engine/transmission computer detected an out-of-range or implausible signal from the brake switch (circuit B). The brake switch tells the PCM/TCM when the brakes are applied, which affects cruise control, torque converter lockup, and certain shift and idle strategies. A faulty signal can cause issues like cruise control not working, harsh shifts, or the converter not unlocking.

What are the most common causes of P0703?

The most common causes of P0703 are: Faulty brake light switch, Misadjusted brake switch, Open or shorted brake switch wiring, Corroded or loose connector at the switch, Blown brake circuit fuse, PCM/TCM input fault. The specific cause varies by vehicle.

How much does it cost to fix P0703?

Repair costs for P0703 range from $30 to $180, depending on the vehicle and root cause.

Which vehicles are affected by P0703?

Au7o has documented P0703 across 1 vehicle models from 1 manufacturers: Chevrolet.

Sources (1)

  • ForumCarComplaints 2004 Chevrolet Malibu - brake light and shift interlock related reports

Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.

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