How to test battery voltage on Mercedes fuel pump?
The red arrow points to the battery positive feed to the pump. The yellow arrow points to the battery negative feed to the pump. You will be testing voltage across the large wires at the connector. Turn the key ON. The DVOM should read battery volts (around 12 volts). If no voltage is found, check the relay and the fuel pump fuse.
Where is the fuel pump located in a Mercedes Benz?
Click here to order! In modern Mercedes-Benz automobiles the fuel pump is electric and located inside the saddle-fuel tank. The fuel pump creates positive pressure in the fuel lines, pushing gasoline to the fuel rail, where the DME controls flow to the engine via a programmed fuel injection map.
How to test the fuel pressure in a Mercedes Benz?
Pressure testing: Connect a fuel pressure test gauge to the test port (red arrow). Next, start or attempt to start the engine. The fuel pressure should be 3.7: 4.2 bar with the engine running or when cranking. Once you test the pressure, recharge the fuel system by cycling the key or running the fuel pump.
Can a faulty fuel pump cause an engine to not start?
The fuel then flows to the fuel rail at a regulated pressure and volume. A faulty fuel pump can cause poor engine performance and hard starting problems. When they fail completely, you may be left with an engine that doesn’t start.
What do I need to check fuel pressure in a Mercedes Benz?
Checking the fuel pressure is very simple. For this test, you will need a fuel pressure gauge. What you need is a fuel pressure gauge with Schrader valve adapter. A great and affordable gauge that we have used in the past is this Actron Fuel Pressure Gauge which works on Mercedes-Benz cars.
Why is my Mercedes Benz starter not working?
Often times, when the starter is defective or seizes up it will blow out the fuse that protect the starter circuit. Another thing that you can try is to hit the starter with a rubber hammer a couple of times. Depending what kind of starter problems you have, the starter may work a few more times.
Why is the battery on my Mercedes Benz not working?
Hint: Starter Problem or Low Battery This may seem obvious, but an old battery is the root of many headaches and can cause all sorts of malfunctions on Mercedes-Benz cars. How old is the battery on your Mercedes-Benz?
What do I need to troubleshoot my Mercedes Benz?
Troubleshooting fuel related problems is not very difficult and you can check the fuel pressure yourself. Checking the fuel pressure is very simple. For this test, you will need a fuel pressure gauge. What you need is a fuel pressure gauge with Schrader valve adapter.