OBD Guide

P1A91

14 Volt Power Module Temperature Sensor 1 Circuit Low Voltage

P1A91 is an OBD-II diagnostic trouble code meaning: 14 Volt Power Module Temperature Sensor 1 Circuit Low Voltage. Common causes: power module temperature sensor malfunction, open or short circuit in the sensor circuit. Estimated repair cost: $17–89.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$17–89 (est.)

Symptoms

  • Check Engine light comes on
  • Possible reduction in electrical system power
  • Errors in the charging system
  • Power module overheating
  • Unstable operation of electrical equipment

Causes

  • Power module temperature sensor malfunction
  • Open or short circuit in the sensor circuit
  • Poor contact in connectors
  • 14V power module faulty
  • Wiring or grounding problems

How to Fix

  1. Check the continuity of the temperature sensor circuit
  2. Inspect connectors and contacts for oxidation or damage
  3. Check the functionality of the temperature sensor
  4. Test the 14V power module
  5. If necessary, replace the sensor or power module

Related codes

FAQ

What does the P1A91 code mean?

P1A91 is an OBD-II diagnostic trouble code that indicates: 14 Volt Power Module Temperature Sensor 1 Circuit Low Voltage

What causes a P1A91 error code?

The most common causes of P1A91 include: Power module temperature sensor malfunction; Open or short circuit in the sensor circuit; Poor contact in connectors; 14V power module faulty.

How do I fix a P1A91 diagnostic trouble code?

To fix P1A91: Check the continuity of the temperature sensor circuit. Inspect connectors and contacts for oxidation or damage. Check the functionality of the temperature sensor. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P1A91?

Yes, but get it checked soon

How much does it cost to fix P1A91?

The estimated repair cost for P1A91 is $17–89. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat