CRITICAL: Brake Booster Pressure Sensor MUST Be Replaced

This is essential for permanent repair success:

Simply repairing or replacing the ABS module alone will NOT fix the problem long-term. The faulty brake booster pressure sensor that caused the original damage must be replaced before reinstalling your repaired ABS module. 

Comprehensive Pre-Repair Diagnostic Testing

• Full fault code analysis and verification and repair
  

Professional Component-Level ABS Module Repair

• Circuit board component replacement and soldering if required
• EEPROM memory chip reset to clear permanent fault storage
  

Extensive Post-Repair Quality Testing

• Full operational testing beyond normal vehicle parameters
• Fault code clearance verification
• Pressure and vacuum response testing
• Final quality control inspection
  

Audi A4 (B8 & B9 Generation)

Part Numbers: 8W0907379E, 8W0907379F, 8W0907379G, 8W0907379J, 8W0907379K, 8W0907379M, 8W0907379Q, 8W0907379AA, 8W0907379AB, 8W0907379AC, 8W0907379AD, 8W0907379AF, 8W0907379AG, 8W0907379AH, 8W0907379AJ 8W0907379GREP 8W0-907-379-G-REP; 8W0-907-379-GREP; 8W0907379G REP
Bosch part number: 0265956241, 0265255815
Other part numbers: 8W0614517AG, 80A907379B, 80A907379BREP 80A-907-379-B-REP; 80A-907-379-BREP; 80A907379B REP

Audi A5 (F5 Generation)

Part Numbers: 8W0907379 , 8W6907379 8W0614517NBEF 8W0-614-517-N-BEF

Audi A6 (C8 Generation)

Part Numbers: 4K0907379 

Audi A7 (C8 Generation)

Part Numbers: 4K8907379 

Audi Q5 / SQ5 (FY Generation)

Part Numbers: 80A907379 

Audi Q7 / SQ7 (4M Generation)

Part Numbers: 4M0907379 , 4M0907379K

Also Compatible:

• VW Touareg (CR) - Part # 4M6907379
• Bentley Bentayga - Part # 36A907379

Dashboard Warning Lights & Messages:

• ABS warning light constantly illuminated (yellow or amber)
• Traction control (ESP/ASR) warning light activated
• "Brake system fault - stop carefully" critical error message
• Early warning: "Brake servo restricted - you can continue driving"
• Red brake warning light with exclamation mark

Brake System Performance Issues:

• Loss of ABS emergency brake assistance
• Reduced power brake assist
• Hard or stiff brake pedal feel
• Increased brake pedal effort required
• Standard braking only (no electronic assistance)
• ESP/traction control disabled

Diagnostic Scan Results:

• Fault Code C123EF0 stored permanently (will NOT clear) in ABS module, Alternative code: C123EFO
• Description: "Hydraulic Brake Booster - Limit Value Reached"
• Additional codes: Brake vacuum sensor faults may also be present
  

Step 1: Diagnostic Testing (24-48 Hours)

Your ABS module arrives at our specialized facility and immediately undergoes comprehensive diagnostic evaluation using professional Hardware-in-the-Loop test equipment. This advanced testing replicates actual vehicle conditions including engine vacuum, brake pressure, wheel speed sensors, and hydraulic demands. We identify all failed components and document pre-repair condition.

Step 2: Expert Component-Level Repair

Our certified automotive electronics technicians perform precision repairs:

• Repair or replace damaged internal components
• Desolder and replace failed circuit board components 
• Reset EEPROM memory chip to factory default state (clears permanent fault)
• Clean and protect against future corrosion
• Reassemble with high-grade sealants and lubricants

Step 3: Post-Repair Verification Testing

Every repaired ABS module undergoes rigorous testing:

• Electronic communication verification
• Fault code clearance confirmation
• Function testing of all safety systems
• Quality control final inspection

Step 4: Return Shipping with Complete Documentation

• Professionally packaged for safe transport
  
• No programming or coding required - your repaired module retains all original vehicle-specific data

Step 5: Customer Completes Sensor Replacement & Reinstallation

Before installing your repaired ABS module, replace the brake booster pressure sensor (typically part #036906051C or vehicle-specific equivalent). Install the repaired ABS module, clear fault code history, and enjoy fully restored brake system performance with lifetime warranty protection.

Environmental Benefits

• Sustainable repair vs. wasteful replacement
• Reduces electronic waste
• Eco-friendly alternative supporting circular economy
• Extends product lifecycle

CRITICAL WARNING: Don't Ignore Early Symptoms!

The Mistake That Costs Thousands

Many Audi owners see the early warning message "Brake servo restricted - you can continue driving" and think it's safe to ignore temporarily. This is a costly mistake.

When you continue driving with this warning:

• The faulty sensor keeps sending bad data
• Your ABS pump activates HBC repeatedly
• Internal components suffer progressive damage
• The fault counter increments with each ignition cycle
• Eventually the system logs permanent fault code C123EF0
• ABS module becomes "bricked" and requires professional repair

Take action at the first warning to replace the brake booster sensor ($50-150 part cost). This prevents the $2,000-3,000 ABS module replacement that follows when ignored. If you already have the C123EF0 fault code stored, our repair service is your most cost-effective solution - but you must still replace the sensor to prevent recurrence.

Common Part Numbers:

• 036906051C (Most common for 2015-2020 Audi models)
• Verify exact part number for your specific model/year
• Available from Audi dealers, online parts retailers. 
  

Q: Will my repaired ABS module need coding or programming?

A: No! Your repaired module retains all original vehicle-specific coding and calibration data. Simply reinstall and clear fault codes - no dealer programming required.

Q: How long does the repair take?

A: Typical turnaround is 2-3 business days from when we receive your module to when it ships back to you. Add shipping time on both ends.

Q: Can I drive my car with the C123EF0 fault?

A: Technically yes, but NOT recommended. You'll have standard braking only without ABS, traction control, or electronic brake assistance. Emergency braking capability is significantly reduced.

Q: Do I need to replace the brake sensor?

A: Absolutely YES. The faulty sensor caused the original ABS damage. Without sensor replacement, the same fault will recur and damage your freshly repaired module.

Q: What if my module can't be repaired?

A: Rare (less than 1% of cases), but if deemed unrepairable, we refund your full repair cost minus a small diagnostic/testing fee.

Q: Will this fix other fault codes too?

A: Our repair addresses the C123EF0 fault and related internal ABS failures. Other unrelated faults (wheel speed sensors, wiring issues, etc.) require separate diagnosis.

Questions? Contact us with your:

• • Vehicle VIN number
• • ABS module part number
• • Current fault codes
• • Vehicle year/model

Our expert technicians will confirm compatibility and guide you through the repair process.

Save Money. Restore Safety. Choose Professional Repair Over Expensive Replacement.

Fast, Reliable, Guaranteed ABS Module Repair Service for 2015-2020 Audi Vehicles

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