OBD Guide

P1C99

Gear Shift Position Sensor 1 Circuit

P1C99 is an OBD-II diagnostic trouble code meaning: Gear Shift Position Sensor 1 Circuit. Common causes: open or short circuit in the sensor circuit, gear position sensor malfunction. Estimated repair cost: $17–56.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$17–56 (est.)

Symptoms

  • Incorrect gear shifting
  • Delays when shifting gears
  • Check Engine Light Is On
  • The transmission goes into emergency mode
  • Cannot determine the current program

Causes

  • Open or short circuit in the sensor circuit
  • Gear position sensor malfunction
  • Poor connection or corroded connectors
  • Wiring harness damage
  • Transmission control module (TCM) malfunction

How to Fix

  1. Check the integrity of the sensor circuit
  2. Check sensor connections and connectors
  3. Check sensor resistance and voltage
  4. Replace the gear position sensor if necessary
  5. Check and replace the Transmission Control Module (TCM) if necessary.

Related codes

FAQ

What does the P1C99 code mean?

P1C99 is an OBD-II diagnostic trouble code that indicates: Gear Shift Position Sensor 1 Circuit

What causes a P1C99 error code?

The most common causes of P1C99 include: Open or short circuit in the sensor circuit; Gear position sensor malfunction; Poor connection or corroded connectors; Wiring harness damage.

How do I fix a P1C99 diagnostic trouble code?

To fix P1C99: Check the integrity of the sensor circuit. Check sensor connections and connectors. Check sensor resistance and voltage. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P1C99?

Yes, but get it checked soon

How much does it cost to fix P1C99?

The estimated repair cost for P1C99 is $17–56. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat