For the last two years I have been pulling the negative battery cable any time I park my 1990 240 Wagon for longer than O/N (one night). There is a 4.8 amp current running all time. I went through the usual process of pulling fuses one at a time and no fuse has any effect on the current. This includes the 25 Amp FI fuse under the hood next to the positive terminal block - also no effect. That is why this has been going on for 2 years unresolved. I haven't had much time to work on the car recently.

I had to replace the alternator last weekend and while the car was up on ramps I tried another electrical experiment - disconnecting the starter. That e like one of the few things that is connected to the battery but does not run through a fuse. Again, no effect. So, I tried tracing out the two smaller wires coming off the positive terminal. One goes to the positive terminal block and the other goes to the 25 Amp fuse. I found that if I disconnected the one that goes to the Pos. term block AND pulled the 25 amp fuse the drain stops.


If that isn't strange enough, I also noticed that if I momentarily either reconnect the wire to the terminal block or momentarily slide the 25 amp fuse back in, and then disconnect either that the current drops SLOWLY from 4.8 amps. Looks like it would take about a minute or more to drop to zero. I haven't had the patience to wait and time it. ;-)

Looking at the wiring diagram online I noticed that about the only place there is a nexus involving the FI fuse circuit and anything running through the ignition switch is the fuel injection relay. I tried pulling that but it had no effect on the drain current.

Since the terminal block feeds the fuse panel and ignition switch and I now know that somehow two circuits are involved I tried going back to the fuse panel WHILE the 25 amp fuse was removed. Sure enough, if I remove fuse #8 I get the slowly dropping current. Now we're getting somewhere, but where?

Any suggestions about where 4.8 amps could be going that involves the FI circuit and circuit #8, and why that current decays slowly when the load is disconnected? This seems like a pretty good head-scratcher.

Broos