Definition of Code P0936
The diagnostic code P0936 indicates an intermittent circuit error in the hydraulic pressure sensor.
What does code P0936 mean?
Code P0936 is a generic OBD-II trouble code that detects an issue with the hydraulic pressure sensor circuit. The purpose of the hydraulic pressure system is to provide energy to assist automatic transmission shift speeds. Each gear is associated with a hydraulic circuit, and when the vehicle requests an upshift or downshift, the different hydraulic circuits engage or disengage to make the shift happen. All of this is controlled by the Powertrain Control Module (PCM) and Transmission Control Module (TCM), which calculate the correct shift strategy by considering various engine factors and conditions. The PCM then monitors the hydraulic pressure by receiving data from the hydraulic pressure sensors. If the PCM receives an abnormal signal, or no signal at all from the hydraulic pressure sensors, the P0936 trouble code may be stored.
What causes code P0936?
The P0936 trouble code is almost always the result of damaged electrical components. This can include blown fuses, corroded cables, shorted or open wires, or a loss of ground. Other potential causes of the code are a faulty hydraulic pressure sensor and a defective PCM or TCM.
What are the symptoms of code P0936?
When the P0936 trouble code is detected, the check engine warning light will likely illuminate on the vehicle’s dashboard. Transmission problems are usually evident, such as failure to shift into certain gears (which can result in slow acceleration or excessive engine RPM) and harsh shifting. Most vehicles will also experience reduced fuel economy.
How does a mechanic diagnose code P0936?
Code P0936 will be diagnosed with a standard OBD-II fault code scanner. A qualified technician will use the scanner to view freeze frame data and assess the P0936 code. The scanner will also be used to check for any other trouble codes, as codes should always be addressed in the order they appear. The codes will then need to be reset and the vehicle restarted, so the mechanic can see if the P0936 code returns. If it does not, a false trigger or intermittent error is likely to blame.
If the code returns, the mechanic will begin by visually inspecting the electrical components of the hydraulic pressure sensor system and replacing any that are damaged. Next, the ground voltage should be checked, and then the mechanic can perform an inspection on the hydraulic pressure sensor. If no issues are found, a thorough inspection of the PCM and TCM will be necessary.
When a component is repaired or replaced, the mechanic will need to reset the codes, restart the vehicle, and check again to see if the P0936 code is still detected. By doing this, the technician will know when the issue has been resolved.
Common mistakes when diagnosing code P0936?
The most frequent mistake made when diagnosing this code is failing to properly follow the OBD-II diagnostic protocol. The protocol must always be followed exactly to ensure that diagnostics and repairs are thorough and effective.
It is quite common for hydraulic pressure sensors to be mistakenly replaced when an electrical component was the only issue in the system.
How severe is code P0936?
In most cases, a vehicle with a P0936 code can still be driven, although there may be driving issues. If the code is not addressed, severe damage can be caused to the transmission, so an inspection should be scheduled as soon as the code is detected.
What repairs can fix code P0936?
Repairs for the P0936 trouble code are:
- Replacement of the system’s electrical components
- Replacement of the hydraulic pressure sensor
- In rare cases, replacement of the PCM or TCM