1988 ford expedition

check engine always on now door ajar alway on dome lights and rear interior and running board lights alway on. when i take out fuse the windows don't open now. any suggestions? need lights but not on all time

Reply to
allpromd
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Something strange *is* going on there, and my first thought is if you have problems with both the interior lights and the power windows you need to check continuity of the drivers' door hinge wiring bundle. Multiple broken wires, and the dome light switch in the door latch (and not a jamb pin switch) would cause oddities like that.

If you open the drivers door and the lights or windows start working, close the door and they stop (or vice versa) and that's it.

The circuit for the dome lights (the step lights are tapped off the dome lights) should have absolutely nothing to do with the circuit for the power window motors. The windows are on a 30A automatic circuit breaker.

Other than that, get a hold of the factory wiring diagram, it often provides valuable clues as to common components and power leads - and don't forget common ground leads. Open grounds are another source of strange stuff.

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Reply to
Bruce L. Bergman

There is an occasional problem with water leakage at the base of the windshield. It is a small leak and often not apparent to the vehicle operator. The water leaks onto the GEM (General Electronics Module). The GEM controls a lot of functions, including the interior lights. It does not turn on the check engine light. You need to have someone read the PCM codes using the appropriate scanner. Since only your lights are acting up, I don't think water contamination of the GEM is your problem. It is much more likely that the interior and exterior lights are on becasue of a sticky door switch.

Here is my recommendation of how to proceed:

1) Clean all the door latches to try and verify that there is not a problem with one of the switches. To do this get a spray can of electrical contact cleaner or WD-40. Using the small tube that comes with the product, spray the interior of the latch from the edge of the door. Really soak things and try to spray the cleaner through the mechanism. There is a switch in the latch. "Gunk" contaminates the switch mechanism preventing it from operating properly when the door is latched. You are trying to wash the gunk out.The switches are seperately replaceable, however, usually the problem is just contamination. 2) Have some one read the PCM codes and have that problem corrected. 3) Check the GEM to verify that a leak is not contaminating the module.

References:

"*FORD SPECIAL MESSAGE #15773 VARIOUS ELECTRICAL CONDITIONS RESULTING FROM WATER INTRUSION INTO THE GEM/CJB SOME 1997-2002 EXPEDITION AND 1998-2002 NAVIGATOR VEHICLES MAY EXHIBIT VARIOUS UNUSUAL ELECTRICAL CONDITIONS, INCLUDING BUT NOT LIMITED TO: FRONT OR REAR BLOWER OR EATC STAYING ON WITH KEY OUT OF THE IGNITION, RADIO STAYING ON AFTER DOORS OPENED AND KEY OUT OF IGNITION, WIPER CIRCUIT FAILURE CODES, AND MULTIPLE SYSTEM WARNING LIGHTS WITH 'SHORT TO POWER' OR 'LOW BATTERY VOLTAGE' DTCS. THESE SYMPTOMS MOST OFTEN OCCUR AFTER A RAIN OR SNOW. THIS MAY BE DUE TO GEM/CJB WATER INTRUSION RESULTING FROM A WINDSHIELD WATER LEAK. TO SERVICE, REMOVE THE GEM AND CJB FROM THE VEHICLE, SEPARATE THEM AND INSPECT FOR WATER CONTAMINATION OR CORROSION. IF FOUND IN EITHER COMPONENT, REPLACE BOTH COMPONENTS AND COMPLETELY RESEAL THE WINDSHIELD. EFFECTIVE DATE: 04/05/2002"

Again, I don't think the GEM is your problem - I think your problem with the lights is the door latch switches.

See:

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Ed

Reply to
C. E. White

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