CodeRegistry
Brands
  1. Home
  2. Carrier
  3. Air Conditioning
  4. A168
About·Privacy·Terms

CodeRegistry — Your global library for technical solutions.

For your safety: always follow the equipment manufacturer’s official manuals. CodeRegistry is an independent help site and is not affiliated with the brands listed here.

A168

A168 - Low Ambient Control Board (SCB2) Comm Failure

Carrier · Air Conditioning

What does A168 mean?

Communication has failed between the main control and the Low Ambient Control Board (SCB2). Cooling function is disabled.

Common Causes

  • Incorrect wiring
  • Loss of power to the SCB2 board
  • Faulty SCB2 board

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Verify power supply to the SCB2 board.

  2. 2

    Check all wiring connections between the main control and the SCB2 board.

  3. 3

    A technician should test the SCB2 board and its communication lines.

Browse all codes in this manual (60)
Verified technical data. Last updated: April 2026

Related Faults

A051A051 - Compressor 1 Stuck On FailureA052A052 - Compressor 2 Stuck On FailureA055A055 - Compressor 1 Stuck On Failure (Circuit B)
Source: Carrier Air Conditioning
Open Manual (Page 100)Search more codes in this manual