Question

hello,
My Mecedez Benz 200E (why is the fuse that controls central lock on my car always cut off(blown off,spark)when ever i put a new one it cut off immediately?

Answer 1

it sounds like you have a short somewhere in the circuit, fuses are there to prevent component damage due to excess current, and current is dependent upon the resistance in the circuit. In the case of a short circuit, the circuit bypasses some of the loads (resistors, capacitors etc,) and hence is much higher through the circuit. In order to protect the fairly delicate components (ie especially the processor and the chipset with the code recognition software) from this higher than rated current, the fuse is the sacrificial piece that opens (breaks) the circuit.

Answer 2

would recommend seeing an auto electrician or more likely taking to your closest mercedes dealership and describing the problem, if it's still under X thousand kms, they should fix for free as it's not regular wear and tear so will be covered under warranty. If not, they'll charge you through the nose, as it's a bit of a specialty field and requires some pretty specific gadgets to diagnose the problem sometimes

Answer 3

Thank you Jack you right about this but do you think that if the resistance of the fuse i replace is lower than the specify one it can also break as a result of low resistance fuse? thanks once again

Answer 4

yeah, definately, however on the fuse cover it should mark what fuse amperage goes in which slot, so check that the fuse you are placing in there has the same maximum ie if you're putting a 2 A fuse in a 10 A slot it'll break every time