Guide To P0538 OBD Error Code Solutions

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The P0538 error code can be defined as A/C Evaporator Temperature Sensor Circuit High.

A P0538 code indicates that the powertrain control module (PCM) has registered voltage readings from the A/C evaporator temperature sensor that are outside of manufacturer’s specifications. Due to this the P0538 trouble code would start triggering up.

This trouble code is generic, which would mean that it can apply to all the vehicles which are equipped with the OBD-II or the vehicles which are made since 1996 up to the present. The specifications on the definition, the troubleshooting steps as well as repairs can always vary from one vehicle make to another. This can happen because of a lot of reasons and the mechanic should diagnose the specific cause for this code.

What causes this problem with the A/C Evaporator Temperature Sensor Circuit High?

• Some wiring problems within the sensor's circuit
• Quirks in the wiring harness connector
• Electrical connection might be intermittent
• The A/C evaporator core might have some faults
• Defaults in the A/C evaporator temperature sensor
• Malfunctioning engine control module
• Problems related to internal resistance

1. Engine Wiring Harness - Defective car Engine Wiring Harness can be a major reason why P0538 code depicts. So, make sure to replace it online so that you don’t have to face any further issues.
2. Air Conditioning Evaporator - Everything is okay with the Engine Wiring Harness and still OBD code P0538 triggering? Then there must be some defects in AC Evaporator. Replace them as soon as possible.
3. Engine Control Module - P0538 code flashing? Get your Engine Control Module inspected from a mechanic.
4. Air Conditioning Compressor Clutch - If everything is alright with PCM, then there is surely some defect in AC Compressor Clutch. Get it replaced before the situation gets worse.
5. Powertrain Control Module - P0538 code can display due to some faults in the Powertrain Control Module. So, it is very important to replace the Powertrain Control Module with us at equitable prices.
6. Air Conditioning Expansion Valve - Do you remember when was the last time you got your car AC Expansion Valve checked up? A faulty AC Expansion Valve can cause a lot of issues like displaying P0538 code.

You might be thinking that how would you diagnose these problems? We at Parts Avatar Canada would help you diagnose the major symptoms easily.

Common Symptoms

• A/C compressor clutch may not engage properly
• No cold air blowing from the air vents
• Fan air temperature might be erratic/fluctuating
• Problems in the proper functioning of the HVAC system

The repairs which you will have to do to correct this fault code are simply straightforward; you can surely pinpoint the necessary repairs on the basis of your diagnosis. Have a look at some common fixes:

• Addition of refrigerant is necessary
• It is very important to replace the evaporator core temperature sensor
• Replace or repair the expansion valve
• The wiring or A/C/climate control head unit should be repaired or replaced as per the need

There is no need to get strained if your OBD Code is still flashing up as we are here at your service. Have a look at our superior variety of hvac system, wire harness connectors, ac temperature sensors, hvac air box, trailer wiring harness, wiring harness kit and many more. Now all your problems would vanish within no time.

Here are some steps which you should follow in order to diagnose this fault code:

• You will need an OBD-II code reader/scanner, digital volt/ohmmeter and a set of A/C gauges or A/C recycling machine with built-in gauges for a proper diagnosis and repair
• You must start your diagnosis by visually inspecting all wiring and connectors. Repair/replace any damaged, disconnected, corroded or shorted wiring, connectors and parts as needed.
• The system should then be retested
• If all wiring, connectors, parts and fuses appear to be in good working order, connect the scanner/code reader to the diagnostic port. Record any stored codes and freeze frame data
• Test drive the vehicle and re-test to see if the code returns. If not, the problem may be an intermittent condition. Intermittent conditions can be a challenge to diagnose correctly and may need to be allowed to worsen and return before a proper diagnosis can be made
• Connect A/C gauges to the proper fittings, start the engine and turn the A/C blower on its highest setting, with A/C on Max. Observe gauge readings and compare to factory specs, adding refrigerant level as needed. Turn the blower speed to Low, then observe gauges for pressure readings
• If system’s low-side pressure falls too much – below 25 psi or so – it can cause a freeze up of the evaporator and a trouble code. If this occurs, the expansion valve could be at fault
• If the A/C system operates normally, perform a resistance test on the evaporator temperature sensor electrical connector
• Compare your findings to factory specs, replace sensor if needed
• If evaporator temperature sensor seems to be within operating norms, disconnect the PCM electrical connector and electrical connector for the climate control head unit. Perform a resistance/continuity test on the evaporator temperature sensor circuit. Repair/replace any shorted or open wiring if indicated. If the evaporator temperature sensor and circuits test as good, suspect the climate control head unit itself or the A/C compressor switch
• Carefully test the unit and compare it to the factory specifications. You can always replace the components as per the requirement

Common Mistakes When Diagnosing The P0538 Code

• The technicians generally overcharge their vehicles system with refrigerant after seeing the P0538 trouble code and it might result in some serious issues
• It is essential to make certain that it’s absolutely necessary to add refrigerant before moving forward and only qualified personnel with the right tools as well as equipment