TorqueMech Beta
TorqueMech OBD Code Guide

P0812 - Reverse Input Circuit

The controller detected an invalid transmission range or start-enable input, which can come from a switch fault, adjustment problem, or circuit issue.

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Code Overview

The controller detected an invalid transmission range or start-enable input, which can come from a switch fault, adjustment problem, or circuit issue.

Common Causes

  • Misadjusted or failed range switch
  • Damaged wiring or corroded connector
  • Shifter linkage issue
  • Control-module input fault

Diagnostic Steps

  1. Confirm the range switch or linkage is adjusted correctly
  2. Inspect connectors for corrosion or water intrusion
  3. Verify the PCM or TCM sees the correct range input
  4. Check related start-enable and reverse-lamp circuits

Likely Repairs & Cost Guides

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Related OBD Codes

Browse nearby codes when systems overlap.

P0811
Excessive Clutch Slippage
Open code guide →
P0813
Reverse Output Circuit
Open code guide →
P0810
Clutch Position Control Error
Open code guide →
P0814
Transmission Range Display Circuit
Open code guide →
P0815
Upshift Switch Circuit
Open code guide →

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