Hi there fine people...
I recently bought a 1998 ML320... After I changed the transmission conductor plate
It was working fine until it did not...
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I'm in need of electrical gurus enlightment...
Symptoms : harder and harder to start the car... Until no start at all...
I Shot in the dark and changed the fuel filter/regulator... No go... So I started to investigate a little bit deeper... I put my ear on the fuel pump while somebody was cranking the engine : no noise of cycling or anything else.. no bueno
Here are all the tests I did... Tell me if I'm wrong
. On my car the fuel pump relay is located in the fuse box under the hood and labeled K3... And the fuse attached to the fuel pump is just above and labeled F38
. I've tried to short the relay legs 1 and 2 with a piece of wire : no go...
. I've checked the fuel pump relay : resistance is good, it's clicking when connected to a 12 v battery... I've tried to replace it with a relay with same ref numbers on it... No go...
. I've checked the fuse : it's visually ok and a continuity test says it's ok
Now this is where it's becoming interesting...
I've put my son in the car to turn the key to contact and/or crank the engine...
. I have 0v at the fuse both at contact or cranking
. I have 0v at the relay between any pair of legs both at contact or cranking...
For good measure I've put the relay back in its socket and did some measurements at the connector behind the left rear wheel...
If I understand correctly the green wire is the positive and the brown wire is the ground giving the juice to the fuel pump...
. No continuity between the BROWN and the chassis
. No voltage between the green and the brown wire...
My conclusion so far is that there's no juice going to the relay hence the fact that it doesn't close hence the fact that there's no juice to the fuse hence the fact that there's no juice to the fuel pump...
I can feel the headache coming...
Help please
Thanks