Engine-Codes - Mercedes-benz - P0748 Mercedes-Benz

P0748 Mercedes-Benz Code - Pressure Control Solenoid 'A' Electrical

- Code Popularity: 22,923 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 3/3
Table of contents

|What are the Possible Causes of the Code P0748 Mercedes-Benz?

  • Dirty transmission fluid
  • Low transmission fluid level
  • Faulty line pressure solenoid valve 'A'
  • Line pressure solenoid valve 'A' harness is open or shorted
  • Line pressure solenoid valve 'A' circuit poor electrical connection

|How to Fix the P0748 Mercedes-Benz Code?

Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.

|Code P0748 Mercedes-Benz Tech Notes

When a transmission solenoid is malfunctioned, in most cases the problem is not the electrical part of the solenoid; the problem is foreign material obstructing the mechanical function of the solenoid or the flow of the fluid through the transmission valve body. If the transmission fluid is dirty, it's recommended to change the transmission fluid and if possible removing the transmission pan for further diagnosis. Excessive debris or metal particles on the transmission pan could be an indication that there is a mechanical transmission failure and that the transmission will need to be rebuilt or replaced.

|What is the Cost to Diagnose the Code P0748 Mercedes-Benz?

Labor: 1.0

The cost to diagnose the P0748 Mercedes-Benz code is 1.0 hour of labor. The auto repair's diagnosis time and labor rates vary by location, vehicle's make and model, and even your engine type. Most auto repair shops charge between $75 and $150 per hour.

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|When is the P0748 Mercedes-Benz Code Detected?

Engine Control Module (ECM) detectes an open or shorted condition on the solenoid circuit

|What are Code P0748 Mercedes-Benz Possible Symptoms?

  • Engine Light ON (or Service Engine Soon Warning Light)
  • Transmission shift shock

|What Does the P0748 Mercedes-Benz Code Mean?

The Pressure Control (PC) Solenoid Valve an electronic pressure regulator that controls transmission line pressure based on current flow through its coil windings. As current flow is increased, the magnetic field produced by the coil moves the solenoid’s plunger further away from the exhaust port. Opening the exhaust port decreases the output fluid pressure regulated by the PC solenoid valve, which ultimately decreases line pressure. The line pressure solenoid valve regulates the oil pump discharge pressure to suit the driving condition in response to a signal sent from the Transmission Control Module (TCM).

Pressure Control Solenoid 'A' Electrical

|Need more Information on the P0748 Mercedes-Benz Code?

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|Need Help with the P0748 Mercedes-Benz Code?

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