B
bedrck46
I recently purchased a nice 2001 Eddie Bauer Expedition that had a few issues.
One of the issues was when you pressed the switch for the rear window defrost it would blow the 40 amp fuse in the Battery Junction (fuse) Box. This would indicate that there was a dead short in the defrost circuit. So where do I start to look for the short?? First I removed the connectors at the rear window grid and also removed the fuse to the heated mirrors. I then replaced the 40 amp fuse and pressed the switch and the fuse blew again. Now I figured that this is going to be a serious problem. Here is where having a good VOM, test light and to me most important a EXECELENT Service Manual is very important. Upon looking at the wiring diagram I see that the power comes from the Battery Junction (FUSE) Box and then goes into the Central Junction (FUSE) Box from there it goes thru the Heated Grid Relay and then it exits the Central Junction Box and goes to the rear heater grid. In that wiring harness are 4 connectors. I removed the Heater Grid Relay and then took my VOM and checked the Fuse Box pins to ground and found a dead short where there shouldn’t be one. There is a connector on the back of the Fuse Box but its not the easiest to get at so my next step was to fine the next connector in the wiring harness and to disconnect it. Upon doing that and re-testing the circuit I still had a short in the circuit. The Power that enters and leaves the Central Junction (FUSE) Box is thru the 2 (Two) connectors on the back of the Fuse Box. At this point I thought that somehow water may have gotten into the fuse box which also has the GEM module attached to it and cause some sort of corrosion thus causing the short. Now to remove the Central Junction Box and GEM Module. Upon removing the CJB and GEM I finally found the problem. The Date of Manufacture on the CJB was 2009 and the date on the GEM was 2005. I have a 2001 Exped. So I can only conclude that these both were change before maybe due to water damage. I have attached pictures of what I found and it appears that whoever changed out these modules was the cause of the current problem. When one of the connectors was reconnected it caused a pin to bend and touch another pin which is a ground circuit. Having a good wiring diagram/manual showed the location of these pins and helped solve the problem. The first picture shows the problem The second pictures shows how it should have been
One of the issues was when you pressed the switch for the rear window defrost it would blow the 40 amp fuse in the Battery Junction (fuse) Box. This would indicate that there was a dead short in the defrost circuit. So where do I start to look for the short?? First I removed the connectors at the rear window grid and also removed the fuse to the heated mirrors. I then replaced the 40 amp fuse and pressed the switch and the fuse blew again. Now I figured that this is going to be a serious problem. Here is where having a good VOM, test light and to me most important a EXECELENT Service Manual is very important. Upon looking at the wiring diagram I see that the power comes from the Battery Junction (FUSE) Box and then goes into the Central Junction (FUSE) Box from there it goes thru the Heated Grid Relay and then it exits the Central Junction Box and goes to the rear heater grid. In that wiring harness are 4 connectors. I removed the Heater Grid Relay and then took my VOM and checked the Fuse Box pins to ground and found a dead short where there shouldn’t be one. There is a connector on the back of the Fuse Box but its not the easiest to get at so my next step was to fine the next connector in the wiring harness and to disconnect it. Upon doing that and re-testing the circuit I still had a short in the circuit. The Power that enters and leaves the Central Junction (FUSE) Box is thru the 2 (Two) connectors on the back of the Fuse Box. At this point I thought that somehow water may have gotten into the fuse box which also has the GEM module attached to it and cause some sort of corrosion thus causing the short. Now to remove the Central Junction Box and GEM Module. Upon removing the CJB and GEM I finally found the problem. The Date of Manufacture on the CJB was 2009 and the date on the GEM was 2005. I have a 2001 Exped. So I can only conclude that these both were change before maybe due to water damage. I have attached pictures of what I found and it appears that whoever changed out these modules was the cause of the current problem. When one of the connectors was reconnected it caused a pin to bend and touch another pin which is a ground circuit. Having a good wiring diagram/manual showed the location of these pins and helped solve the problem. The first picture shows the problem The second pictures shows how it should have been
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