wiring diagram fuel
#1
wiring diagram fuel
Good day, I have a 1997 280E which has been standing for a long while. I tried to start the car only to discover it is not pumping fuel. I tested the fuel pump and will replace it next week. Besides the fuel pump needing to be replaced there is no power coming to the pump. I checked the fuse and the relay, both are fine. The wire supplying power to the coil of the relay also has power, but the grey wire(neutral for the coil) does not have continuity to the body. Since all the neutral wires are brown I suspected this grey wire goes to another sensor / control before connecting to the body. Can anyone help me with a wiring diagram or tell me where this wire is connected to. Thanks for the help, and sorry for the long post. Kind Regards Florian
#4
Out Of Control!!
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The VIN did not provide the specific help I needed---is this an African CKD vehicle??
My problem was that I could not find your starting point---FYI the front SAM has the following relays---3 for wipers, 1 for injection pump, 1 for headlight pump, 1 for horn and 1 for oil cooler fan.
When I checked the DAS I believe the fuel pump is energized(key ON) by the SAM 15\30 circuit and not a relay---thats my problem--are we looking at different areas of the car??
My problem was that I could not find your starting point---FYI the front SAM has the following relays---3 for wipers, 1 for injection pump, 1 for headlight pump, 1 for horn and 1 for oil cooler fan.
When I checked the DAS I believe the fuel pump is energized(key ON) by the SAM 15\30 circuit and not a relay---thats my problem--are we looking at different areas of the car??
#5
Hello Plutoe,
Thanks for your reply. It is a South African vehicle. The relay is under the rear seat next to the battery. It is the only relay there. I followed the wires to the pump and there is power up to the relay. The coil of the relay gets power when I turn on the ignition, but the relay doesn't switch because the coil isn't getting a neutral through the grey wire. Kind regards Florian
Thanks for your reply. It is a South African vehicle. The relay is under the rear seat next to the battery. It is the only relay there. I followed the wires to the pump and there is power up to the relay. The coil of the relay gets power when I turn on the ignition, but the relay doesn't switch because the coil isn't getting a neutral through the grey wire. Kind regards Florian
#6
Out Of Control!!
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Hello Plutoe,
Thanks for your reply. It is a South African vehicle. The relay is under the rear seat next to the battery. It is the only relay there. I followed the wires to the pump and there is power up to the relay. The coil of the relay gets power when I turn on the ignition, but the relay doesn't switch because the coil isn't getting a neutral through the grey wire. Kind regards Florian
Thanks for your reply. It is a South African vehicle. The relay is under the rear seat next to the battery. It is the only relay there. I followed the wires to the pump and there is power up to the relay. The coil of the relay gets power when I turn on the ignition, but the relay doesn't switch because the coil isn't getting a neutral through the grey wire. Kind regards Florian
1 goes to the Z connector which is fed from F3(fuse31),4 is fused from F1(fuse 14), 2 to earth, and 3 to Z connector fed from F7.
When you then look at the fuel pump cable harness in EPC you see connections to the relay,engine harness and two connections to the fuse and relay box near the drivers seat
Last edited by Plutoe; 08-17-2015 at 05:47 PM.