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C1245ModerateChassis

C1245 on 2003-2009 Toyota 4Runner — Manufacturer-specific chassis code - definition not established

1 vehicles · 1 makes · $1,200-$3,000 repair

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How to diagnose and fix C1245: most-reported vehicles

Ranked by owner reports. Each card gives the symptoms, how to confirm the cause, the fix, parts and sources for that vehicle.

Toyota 4Runner · 2003–2009

Link to this issueError Codes:C1391C1252C1256C1245C1246

On 4th-gen 4Runners the integrated ABS actuator/brake master cylinder assembly (with electric pump motor and accumulator) fails internally. The pump motor or accumulator wears out so the pump never reaches pressure and runs continuously; owners get simultaneous ABS, BRAKE, VSC and TRAC warning lights, a loud continuous in-cabin alarm, electronic noise when braking, and a hard or sinking pedal with reduced assist. It is a safety-relevant failure and the assembly is one of the most expensive non-drivetrain parts on the truck. This is distinct from the brake booster/master-cylinder internal-leak issue: this is the ABS hydraulic actuator/accumulator unit.

Common Symptoms

  • ABS, BRAKE, VSC and TRAC lights on together
  • Loud continuous in-cabin warning alarm
  • Brake pump motor runs constantly / electronic noise
  • Hard or sinking brake pedal, reduced assist
  • C-series ABS/brake control codes

How to Fix

First scan and inspect the wheel-speed (ABS) sensors and connectors, as dirty/damaged sensors mimic the symptoms cheaply. If the fault is the actuator/accumulator (continuous pump run, pressure faults), replace the integrated ABS actuator with master cylinder assembly - OEM 47050-60080/47050-60081 (4th gen) - and bleed/initialize the system with a capable scan tool. The part alone runs roughly $1,700-$2,300; remanufactured units are available cheaper.

Typical repair cost:$1,200 - $3,000
Sources for this issue (2)
  • Brake Booster/Accumulator/Master Cylinder Assembly Replacement - Toyota 4Runner Forumforum
  • Alarm + VSC TRAC, TRAC OFF, ABS, Emergency Brake Lights On, no brakes - 2003 4Runner (ToyotaNation)forum

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Community Reported
Medium ConfidenceVerifiedReviewed Jun 2026

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Toyota · 1 issue

C1245 code reference

General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.

Frequently asked questions

What does C1245 mean?

C1245 stands for "Manufacturer-specific chassis code - definition not established." C1245 is a manufacturer-specific chassis code, and available references disagree sharply on what it means. Different sources assign it to a Toyota acceleration/deceleration sensor output fault, a GM ABS valve coil circuit fault, and a Nissan outside air temperature sensor signal fault. No single definition could be confirmed against manufacturer service information, so it is not defined here. Look this code up in the service information for your specific make, model, and year before replacing any part.

What are the most common causes of C1245?

The most common causes of C1245 are: Definition not established - do not diagnose from a generic definition, Check the manufacturer's own service information for this code, A sub-code or symptom byte (for example C1245-45) is often required to identify the exact fault. The specific cause varies by vehicle.

How much does it cost to fix C1245?

Repair costs for C1245 range from $1,200 to $3,000, depending on the vehicle and root cause.

Which vehicles are affected by C1245?

Au7o has documented C1245 across 1 vehicle models from 1 manufacturers: Toyota.

Related codes

  • C1241 · Manufacturer-Specific Chassis Code (commonly Low/High ABS Module Supply Voltage; GM: Variable Effort Steering)
  • C1246 · Master Cylinder Pressure Sensor Malfunction
  • C0031 · Left Front Wheel Speed Sensor Circuit
  • C0034 · Right Front Wheel Speed Sensor Circuit
  • C0036 · Left Front Wheel Speed Sensor Circuit
  • C0037 · Left Rear Wheel Speed Sensor Circuit
  • C0038 · Left Rear Wheel Speed Sensor Circuit
  • C003A · Right Rear Wheel Speed Sensor Circuit
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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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