What is the P0640 fault code What is the description for Intake Air Heater Control Circuit Malfunction How can you fix P0640 fault code What are the causes and symptoms of the P0640 fault?

What is the P0640 Fault code? What does it all mean?

The code P0640 is triggered when the powertrain controller module (PCM), detects an abnormal voltage on the intake heat control circuit. The check engine light must be illuminated if the fault has been present for three consecutive driving cycles in most cases.

The intake air heater element looks like a metal grid. It is powered by electricity from a battery. Heating the intake air by passing it around and through the heating element results in significant heat. Heating the intake helps to stabilize fuel atomization and help evaporate moisture. Heated air is also more efficient. To check if the intake heat exchanger is operating properly, the PCM relies on input data from IAT sensors. IAT sensors are located in front and behind the heating element. These sensors enable the PCM to calculate temperature of air being sucked into engine. The P0640 fault code will be set if the PCM is unable to detect any temperature difference between the air passing through and the heater.

The P0640 fault code can affect vehicles of all makes and models, including but not limited to Citroen, Mercedes-Benz cars, Fords, Mercedes-Benz, Fords, Chevys, GMC Buicks, Chevrolets, and Opel.

What causes the P0640 Fault code?

Below are some reasons to set fault code P0640:

  • – Fused fuse or defective relay for intake air heater
  • – Broken, melted or corroded wires and connectors for heaters and IAT sensors.
  • – Damaged or burned intake air heater element
  • – Defective IAT sensors
  • – Air filter that is extremely dirty or blocked
  • – A PCM that is not working properly or has to be reprogrammed (rarely).

 

What are the P0640 Malfunction Code Symptoms

You may experience the following symptoms if your vehicle has the code P0640:

  • – Illumination for the check engine light
  • If the air entering the engine does not get warm enough, fuel efficiency will decrease.
  • – Idle irregularity in cold engines
  • – Engine cold can cause performance problems.
  • – IAT sensor fault codes can be set

 

How to Fix the P0640 Fault Code

The following repairs may be able to resolve the P0640 fault code:

  • – Repair or replace damaged, disconnected, corroded or shorted components, wiring, and connectors to the intake air heater.
  • – Replace the polluted filter in your air conditioner
  • – Replace the defective intake air heater relay and blow fuses
  • – Replacing defective intake temperature sensors
  • – Replacing the defective intake heat heater element
  • – Repair or reprogramming of the faulty PCM (rarely).

 

How serious is the P0640 Fault code?

Although P0640 doesn’t pose a danger to driving safety, you might notice an increase in fuel consumption or a decrease in engine performance. It is best to have the problem diagnosed and fixed as soon as possible.

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