How to Check Transmission Solenoid Valve with Multimeter?

Safety is always the first consideration before carrying out any maintenance and inspection work. Ensure that construction machinery is at a standstill and turn the engine off, and ensure that components such as the engine starter motor stop working. Also, wear appropriate personal protective equipment such as gloves and goggles to avoid potential hazards.

Step 1: Safety Preparation

Safety is always the primary consideration before carrying out any maintenance and testing work. Ensure that the construction machinery is at a standstill and turn off the engine. Also, wear appropriate personal protective equipment such as gloves and goggles to avoid potential hazards.

Step 2: Prepare tools and materials

You need to prepare the following tools and materials:

Multimeter: for measuring voltage and resistance.

Manuals or drawings: for understanding the circuit connections and parameters of the drive solenoid.

Safety support equipment: such as brackets or pads to ensure the stability of the construction machinery.

Step 3: Find the transmission solenoid valve

Based on the manual or drawing, locate the transmission solenoid valve. This is usually located in the hydraulic system and is responsible for controlling the flow of hydraulic pressure to achieve the movement of mechanical components.

Step 4: Disconnect Power

Before testing, it is important to disconnect the power to the construction machinery to avoid the risk of electric shock. This can be done by unplugging the battery connector or disconnecting the main power switch.

Step 5: Disassemble the drive solenoid

As needed, you may need to disassemble the drive solenoid to gain better access and measurements. During this process, make sure to document each step of disassembly so that subsequent assembly is problem-free.

Step 6: Setting the Multimeter

Set the multimeter to voltage measurement mode. Select the appropriate voltage range to ensure measurement accuracy.

Connect the multimeter's test probe to the drive solenoid's power and ground wires (typically the black and red wires).

Step 7: Measure Voltage

Start the power supply of the construction machinery, but do not start the engine.

Measure the voltage on the power wire of the diesel solenoid valve. Normally, you should be able to read a stable voltage value. Compare this to the expected voltage range provided in the manual to determine if the transmission solenoid is functioning properly.

Step 8: Measure Resistance

Turn off the power to the construction machine.

Set the multimeter to resistance measurement mode and select the appropriate range.

Connect the test probe to both ends of the solenoid coil of the transmission solenoid valve (usually two coil pins).

Record the measured resistance value and compare it to the specifications provided in the manual to determine the health of the solenoid coil.

Step 9: Analyzing the Results

Based on the voltage and resistance measurements, you can initially determine if there is a problem with the transmission solenoid. If you find that the voltage is abnormal or the resistance value is out of specification, you may need to consider further repairs or replacements to prevent damage to other diesel engine spare parts due to abnormal voltage.

Step 10: Reinstall the Drive Solenoid

If you disassembled the transmission solenoid in Step 5, you can now reinstall it by following the documented steps.

By following these steps, you can use a multimeter to test the transmission solenoid valve in your construction machine to help ensure proper operation. However, please note that this is only a basic testing process and for more complex issues, in-depth troubleshooting and repair by a specialized technician may be required. Always read the relevant operating manuals and safety guidelines and follow appropriate safety measures before carrying out any repair work.