Do it yourself
Frequently asked questions about cars and motorcycles

How do you perform the 40 amp fuse test for the pump in a Mercedes A209 CLK?

Model: Mercedes Clk A209, C209, W209 - Years: 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
Part: Fuse box

See other generations:
Video tutorial

To test the 40 amp fuse of the pump in a Mercedes A209 CLK (for example, if it refers to the fuel pump or another system pump), here are the general steps you can follow. Safety first: make sure the car is turned off, the key is removed, and the battery is disconnected to avoid accidental short circuits.

Find the fuse location: The Mercedes A209 (CLK) has a fuse box located under the dashboard (on the driver's side) or in the engine compartment, depending on the type of system you are checking. Check the car manual to locate the specific fuse box for the pump you are testing (fuel pump or other).

Check the fuse indication: each fuse has a numbering that corresponds to the type of device it protects. Identify the 40A fuse (usually highlighted in red or yellow) related to the pump you intend to test.

Visually check the fuse: remove the fuse from its housing. Check if the fuse is burnt.

A damaged fuse will have a thin broken or blackened internal wire. If it is damaged, replace it with a new one of the same value (40A). Test with a multimeter: if the fuse does not appear damaged but you want to make sure it is working correctly, you can test it with a multimeter set to continuity mode.

Place the two terminals of the multimeter on the two ends of the fuse. If the multimeter emits an audible signal (or shows a very low resistance value), the fuse is in good condition.

If there is no continuity, the fuse is burnt and needs to be replaced. Check the pump: Once you have checked or replaced the fuse, you can test the pump (for example, the fuel pump) to make sure it is working correctly, by turning on the car and listening to the sound of the pump starting up. If the fuse is intact and the pump is not working, there may be another issue in the electrical system that requires a more thorough diagnosis, such as a break in the wires or a relay malfunction.

Note: If you do not feel confident in performing these tests on your own, it may be helpful to take the car to a professional.


Posted on 27 February 2025 by ScegliAuto


Related tutorials

Mercedes Clk (2002-2010 / A209, C209, W209) Before you start, open the front passenger door of your Mercedes C-Class CLK A209. Begin by opening the glove compartment. Next, unclip and remove th…
Mercedes Clk (2002-2010 / A209, C209, W209) To replace the fuel pump on the Mercedes CLK, first remove the covers that conceal the fixing screws of the rear seat to loosen these screws and deta…
Mercedes Clk (2002-2010 / A209, C209, W209) On the Mercedes CLK, each fuse is located inside one of the dedicated fuse boxes present on the vehicle: in this type of vehicle, you will find two b…

Other guides you may be interested in

Where is the Engine Fan Fuse Located in a Citroen C3?

The Citroen C3 contains two fuse boxes. The first fuse box is located inside the cabin behind the passenger side glove compartment. The second fuse box is under the bonnet near the battery. The fuse for the engine fan is located in the second fuse box and is labelled F8, rated at 25 Amperes. To replace the fuse, open the fuse box cover, remove the fuse with pliers, and insert a new fuse of the same amperage. Close the fuse box and the bonnet.

Watch the video!


by ScegliAuto

More videos