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P1780ModeratePowertrain

P1780 on 2000-2004 Toyota Corolla — Transmission Control Switch (O/D Cancel) Circuit Out of Self-Test Range

1 vehicles · 1 makes · $600-$1,400 repair

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Most Reported On

2000-2004Toyota Corolla

P1780 is an OBD-II diagnostic trouble code meaning “Transmission Control Switch (O/D Cancel) Circuit Out of Self-Test Range.” This manufacturer-specific code (Ford, Lincoln, Mazda, Mercury) means the computer did not see the expected change of state from the Transmission Control Switch (the Overdrive Off / O-D Cancel or Tow-Haul button) during its self-test. That switch tells the transmission whether to allow overdrive, and if its signal is stuck or the wiring is faulty, the PCM/TCM flags it. You may notice the overdrive light flashing or the transmission not engaging or canceling overdrive properly. It is usually a switch or wiring problem rather than internal transmission damage. This code is most commonly reported on 2000-2004 Toyota Corolla, with repair costs ranging from $600 to $1,400.

On This Page

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

1Faulty or stuck overdrive/transmission control switch
2Damaged or corroded wiring at the switch or transmission connector
3Loose or corroded transmission range connector pins
4Open or shorted switch circuit
5Moisture intrusion at the connector
6Faulty PCM/TCM input (less common)

Typical Repair Cost

$600 - $1,400

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

Diagnostic Tools

To diagnose P1780, 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

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

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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)
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  • 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
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  • Free lifetime updates via Wi-Fi
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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.

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Vehicles Affected (1)

Toyota P1780 page →
CorollaCritical

ECM/PCM Failure Causing Harsh Shifting, No-Start, and MIL Illumination

2000-2004$600-$1,4000 reports

Related Codes (8)

P0020Camshaft 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 PerformanceP0093Fuel System Leak Detected - Large LeakP00B6Radiator Coolant Temperature / Engine Coolant Temperature Correlation

FAQ

What does P1780 mean?

P1780 stands for "Transmission Control Switch (O/D Cancel) Circuit Out of Self-Test Range." This manufacturer-specific code (Ford, Lincoln, Mazda, Mercury) means the computer did not see the expected change of state from the Transmission Control Switch (the Overdrive Off / O-D Cancel or Tow-Haul button) during its self-test. That switch tells the transmission whether to allow overdrive, and if its signal is stuck or the wiring is faulty, the PCM/TCM flags it. You may notice the overdrive light flashing or the transmission not engaging or canceling overdrive properly. It is usually a switch or wiring problem rather than internal transmission damage.

What are the most common causes of P1780?

The most common causes of P1780 are: Faulty or stuck overdrive/transmission control switch, Damaged or corroded wiring at the switch or transmission connector, Loose or corroded transmission range connector pins, Open or shorted switch circuit, Moisture intrusion at the connector, Faulty PCM/TCM input (less common). The specific cause varies by vehicle.

How much does it cost to fix P1780?

Repair costs for P1780 range from $600 to $1,400, depending on the vehicle and root cause.

Which vehicles are affected by P1780?

Au7o has documented P1780 across 1 vehicle models from 1 manufacturers: Toyota.

Sources (1)

  • TSBToyota Warranty Enhancement Program ZE7 / ECM Coverage for 2005 and Earlier Corolla/Matrix

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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