OBD Guide

P181C

Internal Mode Switch 2 R1 Circuit Low Voltage

P181C is an OBD-II diagnostic trouble code meaning: Internal Mode Switch 2 R1 Circuit Low Voltage . Common causes: open or short circuit in the mode switch circuit, poor contact in circuit connectors. Estimated repair cost: $17–89.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$17–89 (est.)

Symptoms

  • Incorrect gear shifting
  • Check engine light comes on
  • Transmission of the gearbox into emergency mode
  • Problems determining the current transmission mode
  • Difficulty switching between modes (P, R, N, D)

Causes

  • Open or short circuit in the mode switch circuit
  • Poor contact in circuit connectors
  • Malfunction of the internal mode switch
  • Transmission control module (TCM) problems
  • Corroded or damaged wiring

How to Fix

  1. Check the integrity of the mode switch circuit
  2. Inspect and clean the contacts in the connectors
  3. Check the voltage at the mode switch
  4. If necessary, replace the internal mode switch
  5. Check and replace wiring harness if necessary

Related codes

FAQ

What does the P181C code mean?

P181C is an OBD-II diagnostic trouble code that indicates: Internal Mode Switch 2 R1 Circuit Low Voltage

What causes a P181C error code?

The most common causes of P181C include: Open or short circuit in the mode switch circuit; Poor contact in circuit connectors; Malfunction of the internal mode switch; Transmission control module (TCM) problems.

How do I fix a P181C diagnostic trouble code?

To fix P181C: Check the integrity of the mode switch circuit. Inspect and clean the contacts in the connectors. Check the voltage at the mode switch. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P181C?

Limited driving only, diagnose soon

How much does it cost to fix P181C?

The estimated repair cost for P181C is $17–89. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat