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Vintage Cars/79 280 sl fuel pump relay


QUESTION: hi. I replaced the fuel pump and filter and engine ran fine. now will not start and no voltage at pump. I would like to find the relay to replace or test by shorting out 30 and 87? (right)? I gad the fuse box translated into English. all fuses are good.
I will greatly appreciate all help.

ANSWER: Id retrace my steps , if after the work it ran fine, and now it does not suggests something related , try running 12 V to pump direct to make sure it is OK and then look for fuses or open shorts.  Relay I believe for that car is the basic "cube relay"

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QUESTION: thanks for info. the battery light is on even when the ignition is turned off.sparks at neg. battery termanal when taking it on and off,shows that something is drawing current even thou everything is off. ideas? where is the fuel pump relay?
all fuses im fuse box on passenger side box<test good.

look for engine ground strap.  using an electrical tester, perform the following

this may help, many of my friends on that site

trace power lead back to relay

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I can answer questions on W110/W111/ W114/ W115 /W(R)107/W123/W126 , and Finny Mercedes models 1962-1985. I have rebuilt many of these cars and have problem solved many issues. I have access to much of the technical data and have detailed instructions on fixing the most common issues. Vintage US 1950-1989 and other foreign cars as well If you are going to ask me about car value, please provide ample information on service history, rust issues, and current "needs". Pictures are helpful. Disclaimer on value - I can only give you data on what the market is bringing, and may not be what you want to hear!


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