Let someone turn on the starter switch while you stand near the engine. When the starter motor solenoid engages, you should hear a clicking sound. If you hear a clicking sound but the starter motor isn't moving, the solenoid could be engaging but not receiving enough battery power.
Let someone turn on the ignition key or press the starter button. Observe the light — if it doesn't turn on, the solenoid is likely failing to transfer power and might need replacement. However, if the light turns on but there's no clicking sound or starter engagement, the issue lies with the car starter.
For irrigation applications, a solenoid is considered to be good if its resistance is between 20 - 60 ohms. It is best to compare resistance measurements to that of a new solenoid. Example, if a solenoid measures 44 ohms, it would be considered good because it is between 20 - 60 ohms.
How many ohms should a starter solenoid read? The resistance should be between 0.2 and 0.6 ohms, which is a sign that the solenoid is in good working order. If you get any other reading, then it means that your starter solenoid needs to be replaced.
Rusting, power failure, irregular pressure, missing equipment, an incorrect amount of voltage or current, dirt stuck in the system and corrosion are some of the possible reasons why a solenoid valve may not properly close or open.
When a solenoid is first energized, its coil receives a pulse of high inrush current that decreases as the plunger closes. If the plunger does not close, the high inrush current continues, which can cause the coil to overheat and burn out. This is the most common cause of solenoid failure and spotting it is easy.
Signs of a Bad Starter Solenoid
It usually means there's a faulty connection in the solenoid. Another common symptom is a single clicking noise when you turn the key.
Abnormally high or abnormally low ambient temperatures to which a solenoid is exposed for an extended time may cause a solenoid to burn out. High Temperature. Coil insulation may be damaged and one layer of wire may short to the next layer. A heat shield or baffle will give some protection against radiated heat.
Solenoid coil failure can be caused by a number of factors. Applying an incorrect voltage to the coil will cause it to fail and may cause the coil to burn out. Electrical surges or spikes may also damage the coil. Burnt out coils cannot be repaired and will need to be replaced.
Every solenoid valve has a nominal actuation voltage, which is usually based on common power supply voltages such as 12 VDC, 24 VDC, 110 VAC, or 220 VAC. The nominal voltage is typically printed somewhere on the valve body or coil and is the voltage required to actuate (shift) the valve.
Incorrectly wiring a starter will have a huge impact on how well it performs. “Bigger displacement requires you to rethink things, just like with fuel delivery, valvetrain parts, and so on. The starter got bigger and the output grew, so the wire must get bigger too.
So can a bad starter drain your battery? The short answer is: Yes, it can. It could also drain the battery even faster if you repeatedly try to start your car with a faulty starter. A faulty starter is also one of the leading causes of battery overcharging.
Checking at the solenoid and other parts
Connect the voltmeter across the solenoid terminals, the negative lead on the feed (battery) side, the positive on the starter side.
Usually a rapid clicking noise is a good indication that your starter motor isn't getting enough electrical current to engage – basically your solenoid is trying to engage but can't make the connection.
2W/12V=0.1667A or 72 ohms for the coil DCR.