View Single Post
Old 05-16-2008, 06:46 PM   #3 (permalink)
augapfel
BenzWorld Elite
 
augapfel's Avatar
 
Date registered: Jan 2006
Vehicle: 88 260E, 88 300E x 2, 88 300TE x 2
Location: Just west of Philly
Posts: 1,413
It sounds like a previous owner may have installed a set of jumper wires to get around a power-to-the-fuel-pumps problem. He/she probably connected those loose wires directly to the battery terminals to start the engine when the pumps wouldn't run. Weird. Maybe he/she looked at the price of a fuel pump relay...

As for opening up relay, don't. You would be amazed at all the crap in there. It is *far* from a normal relay with only a coil and contacts. That box is packed with resistors, capacitors, little circuit boards, and even some integrated circuits. That's becasue the "fuel pump relay" does a lot, lot more than power the fuel pumps.
If you can figure out what's going on in there you're on your way to a career in electrical engineering.
augapfel is offline   Reply With Quote