B1280 code definition
The B1280 trouble code detects an error with the servo motor potentiometer coolair circuit.
What the B1280 code means
The B1280 code is a generic OBD-II trouble code that notes a malfunction with the servo motor potentiometer cool air circuit. The potentiometer acts as a voltage divider for the cool air system, and therefore allows the air to be adjusted. If a circuit error is detected in the servo motor potentiometer, then the B1280 trouble code may be stored.
What causes the B1280 code?
Some causes for the B1280 trouble code include:
- Faulty potentiometer
- Defective servo motor
- Damaged or defective electrical components, such as fuses, connectors, wires
- In rare cases, a defective body control module, climate control module, or powertrain control module (PCM)
What are the symptoms of the B1280 code?
The B1280 trouble code may be joined by an illuminated check engine soon Warning Light, or a blinking A/C light on the climate controls. The vehicle will usually experience problems with the climate control system, such as an inability to produce cold air through the vents.
How does a mechanic diagnose the B1280 code?
The B1280 code will be diagnosed with the aid of an OBD-II trouble code scanner. A reputable technician will use the scanner to view the freeze frame data and gather information about the B1280 code. The mechanic will also check to see if any other trouble codes are present. If multiple codes are detected, then they will need to be diagnosed in the order in which the scanner displays them. The mechanic will then reset the trouble codes, restart the vehicle, and check for the presence of the B1280 code. If the code is no longer detected, then it was likely triggered inaccurately, or is the result of an intermittent issue.
If the code is still detected after the reset, then a visual inspection will be performed on the electrical components in the system. Any wires that are shorted or damaged, connectors that are open or corroded, or fuses that are blown will need to be replaced. The servo motor and potentiometer will then be inspected.
After any part is replaced, the mechanic will reset the trouble codes, restart the vehicle, and again check to see if the B1280 code is present. By doing this, the technician will know as soon as the B1280 code is resolved.
Common mistakes when diagnosing the B1280 code
The most frequently made mistake when diagnosing this code comes from not properly following the OBD-II diagnosis protocol. It is extremely important that technicians always comply with the protocol, as it helps ensure a diagnosis that is efficient and devoid of erroneous repairs.
Fully functional potentiometers and servo motors are often replaced when the only issue was a damaged wire or connector.
How serious is the B1280 code?
A vehicle with the B1280 trouble code will still be drivable, and won’t experience any drivability problems. The climate control system may not work well, and the vehicle may not be able to produce cold air, so the vehicle should be inspected as soon as is convenient.
What repairs can fix the B1280 code?
Repairs for the B1280 trouble code include:
- Potentiometer replacement
- Servo motor replacement
- Replacement of electrical components in the system
- In very rare cases, replacement of the PCM, climate control module, or body control module
Additional comments for consideration regarding the B1280 code
It is very rare for a defective control module to be the cause of the B1280 trouble code. Mechanics should always inspect all potential causes before a controller is assumed to be faulty. In the event that the PCM, climate control module, or body control module does need to be replaced, then it will also need to be reprogrammed.
Need help with a B1280 code?
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This article originally appeared on YourMechanic.com as B1280 OBD-II Trouble Code: Servo Motor Potentiometer Coolair Circuit Failure and was authored by Brady Klopfer.