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C1148CriticalBrakes

C1148: ABS/TCS System Relay Circuit Open

1 vehicles · 1 makes · $1,500-$4,000 repair

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C1148 is an OBD-II diagnostic trouble code meaning “ABS/TCS System Relay Circuit Open.” The ABS/traction control system relay circuit is open. ABS and TCS are completely disabled. This code appears across 1 vehicle models from 1 manufacturers, with repair costs ranging from $1,500 to $4,000.

On This Page

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

1Failed ABS relay
2Blown fuse
3Wiring open circuit
4Corroded relay socket
5ABS module power supply fault

Typical Repair Cost

$1,500 - $4,000

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

Diagnostic Tools

To diagnose C1148, 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
Check Price on Amazon
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)
Check Price on Amazon
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
Check Price on Amazon

As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.

Vehicles Affected (1)

A6 allroadCritical

Adaptive Air Suspension Spring Bladder Leaks

2020-2026$1,500-$4,000420 reports

Related Codes (8)

C1140RR ABS Channel Malfunction01315ABS Hydraulic Return Pump (VAG)01772Brake Light Switch (VAG)02250ABS Wheel Speed Sensor (VAG)C002487Electronic Brake Force Distribution FaultC0035Left Front Wheel Speed Sensor CircuitC0040Right Front Wheel Speed Sensor CircuitC0045Left Rear Wheel Speed Sensor Circuit

FAQ

What does C1148 mean?

C1148 stands for "ABS/TCS System Relay Circuit Open." The ABS/traction control system relay circuit is open. ABS and TCS are completely disabled.

What are the most common causes of C1148?

The most common causes of C1148 are: Failed ABS relay, Blown fuse, Wiring open circuit, Corroded relay socket, ABS module power supply fault. The specific cause varies by vehicle.

How much does it cost to fix C1148?

Repair costs for C1148 range from $1,500 to $4,000, depending on the vehicle and root cause.

Which vehicles are affected by C1148?

Au7o has documented C1148 across 1 vehicle models from 1 manufacturers: Audi.

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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