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B1802MinorBody

B1802: Lamp Turn Signal Rear Output Circuit (manufacturer-specific)

2 vehicles · 1 makes · $300-$900 repair

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Most Reported On

2009-2013Toyota Corolla2006-2012Toyota RAV4

B1802 is an OBD-II diagnostic trouble code meaning “Lamp Turn Signal Rear Output Circuit (manufacturer-specific).” B1802 is a manufacturer-specific body code, associated mainly with Ford-family lighting systems, that generally indicates a fault in the rear turn-signal lamp output circuit detected by the lighting/body control module. Because it is manufacturer-specific, the precise wording and fault type (open, short, or failure) can vary by make and model and should be confirmed against the vehicle's service information. The practical effect is typically an inoperative or improperly functioning rear turn signal. This code is most commonly reported on 2009-2013 Toyota Corolla, and 2006-2012 Toyota RAV4, with repair costs ranging from $300 to $900.

On This Page

  • Common Causes
  • Repair Cost
  • Vehicles (2)
  • Related Codes
  • FAQ
  • Sources (1)
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Common Causes

1Fault (short or open) in the rear turn-signal wiring
2Faulty rear turn-signal bulb
3Corroded or damaged bulb socket/connector
4Chafed or pinched rear harness
5Water intrusion in the rear lamp assembly
6Internal fault in the lighting/body control module

Typical Repair Cost

$300 - $900

Based on 2 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.

Diagnostic Tools

To diagnose B1802, 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)
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  • Oil reset, EPB, BMS, TPMS, injector coding
  • 7-inch touchscreen with Android OS
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Vehicles Affected (2)

Toyota B1802 page →
CorollaModerate

Airbag Warning Light from Spiral Cable (Clock Spring) Failure

2009-2013$350-$9000 reports
RAV4Moderate

Steering Column Spiral Cable Failure Causing Airbag/SRS Light and Loss of Horn or Wheel Controls

2006-2012$300-$8000 reports

Related Codes (8)

B1801Lamp Turn Signal Front Output Circuit Short to GroundB0081First Row Center Seatbelt Load Limiter Deployment Control (Subfault)B0092Left Side Restraints Sensor 2 (Subfault)B0098Right Side Restraints Sensor 3 (Subfault)B00A0Occupant Classification System (Subfault)B0229Manufacturer-Specific Body Code (GM: Air Recirculation Door Position Feedback Circuit Actuator Range/Performance)B0408Temperature Control (Air Mix) Circuit MalfunctionB0414Manufacturer-Specific Body Code (GM: A/C Air Temperature Left Feedback Circuit Actuator Range/Performance)

FAQ

What does B1802 mean?

B1802 stands for "Lamp Turn Signal Rear Output Circuit (manufacturer-specific)." B1802 is a manufacturer-specific body code, associated mainly with Ford-family lighting systems, that generally indicates a fault in the rear turn-signal lamp output circuit detected by the lighting/body control module. Because it is manufacturer-specific, the precise wording and fault type (open, short, or failure) can vary by make and model and should be confirmed against the vehicle's service information. The practical effect is typically an inoperative or improperly functioning rear turn signal.

What are the most common causes of B1802?

The most common causes of B1802 are: Fault (short or open) in the rear turn-signal wiring, Faulty rear turn-signal bulb, Corroded or damaged bulb socket/connector, Chafed or pinched rear harness, Water intrusion in the rear lamp assembly, Internal fault in the lighting/body control module. The specific cause varies by vehicle.

How much does it cost to fix B1802?

Repair costs for B1802 range from $300 to $900, depending on the vehicle and root cause.

Which vehicles are affected by B1802?

Au7o has documented B1802 across 2 vehicle models from 1 manufacturers: Toyota.

Sources (1)

  • TSBToyota Warranty Enhancement Program ZE5 – Spiral Cable

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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