124 fuel pump relay.

docmercquad

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Your Mercedes
E320 1995/280TE 1994 /1984 230CE/ 2001 320 AMG
Hi ,my 280TE 124 has intermittent starting or sometimes cuts out after a few minutes. The fuel pump is OK, I have supplied 12 volts directly to it via pins 30 and 87. This relay is the small green one 001 542 96 19 with the 10 amp fuse on top. It is dated 15/6/2018. How long are these relays supposed to last?. It checks OK with a multimeter, but will it cope under load.? The fuel pump is drawing 6.5 amps. Thanks for any feedback.
 

DREAMER NO2

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W124 2.6E M103 1989
How long was it when you last replaced all items in the HT system etc ? The right name for the relay is the - comfort relay . If i am right it helps to run three other items ,one being the fuel pumps. It looks like relay problem .But after all so many other items can show up with the same problem. thats why i go through all the HT side first .Along with all the fuses in the fuse box .
 
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docmercquad

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E320 1995/280TE 1994 /1984 230CE/ 2001 320 AMG
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Hello Dreamer No2,
Thanks for your reply. The whole HT system and fuses are all new. A new fuel pump relay has cured the problem. What I was asking is how long do these relays generally last, some say they should last the life of the car, others are not so sure. Perhaps I got a dud relay, but it was supplied by a Mercedes main dealer. Anyway all,s well at this stage. Fingers crossed.
 

DREAMER NO2

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W124 2.6E M103 1989
There are other factors that can shorten the life of the relays . [1] short on the fuel pumps being only one . And [ 2 ] some models had a biodegradable insulation on the wiring looms . My relays as been on the car from day one, back in 1989 . But i do keep a spare in my car at all times along with an OVP relay. Best to use MB parts a good known factor is genuine Mercedes parts do last longer. Always use the same part number as the part your replacing ..so many owners see a part that looks the same [ but it is not ] fit it in ,, and this will cause more problems down the way .
Good luck shout up if we can help more
 
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docmercquad

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E320 1995/280TE 1994 /1984 230CE/ 2001 320 AMG
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Speaking of wiring looms, do you have a part number for the second wiring loom from the ECU that supplies the fuel pump, knock sensors etc.
I see your 124 is a M 103 engine, so it will not be the same as my M104, but perhaps you have a number stored somewhere. Main dealers have no idea.
There is a connector labelled X36/2 which joins the ECU via this second wiring loom to the fuel pump relay. I would have thought it would be behind the ECU in the engine compartment, but I am blowed if I can find it. By the way this is from my second 124 3.2 litre still with the M 104 engine. Have you come across this.? The blue/red lead from the ECU to the fuel pump relay has voltage intermittently. I have had to bypass the whole system and take a direct lead from terminal X12/3 to the relay. Not ideal.
 


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