Clicking relay

[marriedmanw]

I've developed a problem with an 02 Ford Expedition that I'm having trouble resolving. Within the past two weeks if truck sits for awhile the battery would be drained and have to be jumped. Since this is a work vehicle it sometimes sits for days before using again and each time the battery is drained. Checked to ensure that interior lights, radio, lights, etc are all off when parked.

Jumped truck and took to parts store and had the battery and alternator tested which passed. Stopped and restarted truck 3 times that day and cranked each time without problems.

Today opened the door and hear a loud clicking sound which pinpointed to the fuse box. Started to remove fuses one at a time till noise stopped which landed me on a 5A Relay for the Overhead Trip Computer Cluster.

Is is normal for relays to wear out and drain battery, or is the problem still elsewhere? The motor is newer but the body has over 200K on it so not sure if a ground wire is breaking or coming loose?

 

[martin]

Relays do wear out but not in a manner that will cause that kind of issue. Something is causing the relay to stay energized (or try). Whichever circuit that is feeding that relay might also be feeding other circuits.
there are a few posts about eec relays staying stuck on, you might try pulling that relay and see if it stops the battery from draining, it should be next to the fuel pump relay.

 

[Earl43P]

I suggest you leave that fuse out and see if it stays charged or continues to drain.

You might also google "parasitic drain" and follow some of those tips. You've already got the right idea by pulling fuses, just need to hook up an amp meter to the battery lead and continue the process of elimination.